Add Slice 4 tuner stack with AGENTS-compliant core types and HTTP API.

Introduces Si4684/ADAU1701 drivers, TunerService, FrequencyKHz,
SeekDirection, /api/tuner routes without file-scope globals, host tests,
and firmware blob tooling (binaries remain gitignored).

Co-authored-by: Cursor <cursoragent@cursor.com>

Software/.gitignore

@@ -15,3 +15,9 @@ docs/api/
 .vscode/
 .idea/
 .DS_Store
+__pycache__/
+*.pyc
+
+# Proprietary Si4684 firmware blobs (Skyworks / uGreen — local only, not in git)
+Firmware/Si4684-Firmware/*.bin
+Firmware/Si4684-Firmware/.ugreen-extract-*/

Software/CMakeLists.txt

@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.16)
 
 include($ENV{IDF_PATH}/tools/cmake/project.cmake)
 
-# Nested driver components live under components/drivers/
+# Nested driver/service components live under components/
-set(EXTRA_COMPONENT_DIRS "components/drivers")
+set(EXTRA_COMPONENT_DIRS "components/drivers" "components/services")
 
 project(digiradio)

Software/Firmware/ADAU1701-Firmware/DigiRadio_IC_1_PARAM.h

@@ -0,0 +1,443 @@
+/*
+ * File:           C:\Users\mikbi\Documents\Allegati\Desktop\DigiRadio\DigiRadio_IC_1_PARAM.h
+ *
+ * Created:        Monday, July 6, 2026 2:41:28 PM
+ * Description:    DigiRadio:IC 1 parameter RAM definitions.
+ *
+ * This software is distributed in the hope that it will be useful,
+ * but is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * This software may only be used to program products purchased from
+ * Analog Devices for incorporation by you into audio products that
+ * are intended for resale to audio product end users. This software
+ * may not be distributed whole or in any part to third parties.
+ *
+ * Copyright ©2026 Analog Devices, Inc. All rights reserved.
+ */
+#ifndef __DIGIRADIO_IC_1_PARAM_H__
+#define __DIGIRADIO_IC_1_PARAM_H__
+
+
+/* Module Si4674 - Multiple Volume Control*/
+#define COUNT_SI4674                                   2
+#define DEVICE_SI4674                                  "IC1"
+#define ADDR_SI4674                                    0
+#define FIXPT_SI4674                                   0x00800000
+#define VALUE_SI4674                                   SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_SI4674                                    SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_SI4674_1                                  1
+#define FIXPT_SI4674_1                                 0x00800000
+#define VALUE_SI4674_1                                 SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_SI4674_1                                  SIGMASTUDIOTYPE_FIXPOINT
+
+/* Module ESP32 - Multiple Volume Control*/
+#define COUNT_ESP32                                    2
+#define DEVICE_ESP32                                   "IC1"
+#define ADDR_ESP32                                     2
+#define FIXPT_ESP32                                    0x00800000
+#define VALUE_ESP32                                    SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_ESP32                                     SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_ESP32_1                                   3
+#define FIXPT_ESP32_1                                  0x00800000
+#define VALUE_ESP32_1                                  SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_ESP32_1                                   SIGMASTUDIOTYPE_FIXPOINT
+
+/* Module St Mixer1 - Stereo Mixer*/
+#define COUNT_STMIXER1                                 2
+#define DEVICE_STMIXER1                                "IC1"
+#define ADDR_STMIXER1_ST0_VOLUME                       4
+#define FIXPT_STMIXER1_ST0_VOLUME                      0x00800000
+#define VALUE_STMIXER1_ST0_VOLUME                      SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_STMIXER1_ST0_VOLUME                       SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_STMIXER1_ST1_VOLUME                       5
+#define FIXPT_STMIXER1_ST1_VOLUME                      0x00800000
+#define VALUE_STMIXER1_ST1_VOLUME                      SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_STMIXER1_ST1_VOLUME                       SIGMASTUDIOTYPE_FIXPOINT
+
+/* Module Param EQ1 - Parametric EQ*/
+#define COUNT_PARAMEQ1                                 60
+#define DEVICE_PARAMEQ1                                "IC1"
+#define ADDR_PARAMEQ1_ST0_B0                           6
+#define FIXPT_PARAMEQ1_ST0_B0                          0x007FC365
+#define VALUE_PARAMEQ1_ST0_B0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.998150511190452)
+#define TYPE_PARAMEQ1_ST0_B0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST0_B0                           6
+#define FIXPT_PARAMEQ1_ST0_B0                          0x007FC365
+#define VALUE_PARAMEQ1_ST0_B0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.998150511190452)
+#define TYPE_PARAMEQ1_ST0_B0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST0_B1                           7
+#define FIXPT_PARAMEQ1_ST0_B1                          0xFF007936
+#define VALUE_PARAMEQ1_ST0_B1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(-1.9963010223809)
+#define TYPE_PARAMEQ1_ST0_B1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST0_B1                           7
+#define FIXPT_PARAMEQ1_ST0_B1                          0xFF007936
+#define VALUE_PARAMEQ1_ST0_B1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(-1.9963010223809)
+#define TYPE_PARAMEQ1_ST0_B1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST0_B2                           8
+#define FIXPT_PARAMEQ1_ST0_B2                          0x007FC365
+#define VALUE_PARAMEQ1_ST0_B2                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.998150511190452)
+#define TYPE_PARAMEQ1_ST0_B2                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST0_B2                           8
+#define FIXPT_PARAMEQ1_ST0_B2                          0x007FC365
+#define VALUE_PARAMEQ1_ST0_B2                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.998150511190452)
+#define TYPE_PARAMEQ1_ST0_B2                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST0_A0                           9
+#define FIXPT_PARAMEQ1_ST0_A0                          0x00FF86AE
+#define VALUE_PARAMEQ1_ST0_A0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1.99629760176912)
+#define TYPE_PARAMEQ1_ST0_A0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST0_A0                           9
+#define FIXPT_PARAMEQ1_ST0_A0                          0x00FF86AE
+#define VALUE_PARAMEQ1_ST0_A0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1.99629760176912)
+#define TYPE_PARAMEQ1_ST0_A0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST0_A1                           10
+#define FIXPT_PARAMEQ1_ST0_A1                          0xFF807919
+#define VALUE_PARAMEQ1_ST0_A1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(-0.996304442992686)
+#define TYPE_PARAMEQ1_ST0_A1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST0_A1                           10
+#define FIXPT_PARAMEQ1_ST0_A1                          0xFF807919
+#define VALUE_PARAMEQ1_ST0_A1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(-0.996304442992686)
+#define TYPE_PARAMEQ1_ST0_A1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST1_B0                           11
+#define FIXPT_PARAMEQ1_ST1_B0                          0x00800000
+#define VALUE_PARAMEQ1_ST1_B0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_PARAMEQ1_ST1_B0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST1_B0                           11
+#define FIXPT_PARAMEQ1_ST1_B0                          0x00800000
+#define VALUE_PARAMEQ1_ST1_B0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_PARAMEQ1_ST1_B0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST1_B1                           12
+#define FIXPT_PARAMEQ1_ST1_B1                          0x00000000
+#define VALUE_PARAMEQ1_ST1_B1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST1_B1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST1_B1                           12
+#define FIXPT_PARAMEQ1_ST1_B1                          0x00000000
+#define VALUE_PARAMEQ1_ST1_B1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST1_B1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST1_B2                           13
+#define FIXPT_PARAMEQ1_ST1_B2                          0x00000000
+#define VALUE_PARAMEQ1_ST1_B2                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST1_B2                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST1_B2                           13
+#define FIXPT_PARAMEQ1_ST1_B2                          0x00000000
+#define VALUE_PARAMEQ1_ST1_B2                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST1_B2                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST1_A0                           14
+#define FIXPT_PARAMEQ1_ST1_A0                          0x00000000
+#define VALUE_PARAMEQ1_ST1_A0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST1_A0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST1_A0                           14
+#define FIXPT_PARAMEQ1_ST1_A0                          0x00000000
+#define VALUE_PARAMEQ1_ST1_A0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST1_A0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST1_A1                           15
+#define FIXPT_PARAMEQ1_ST1_A1                          0x00000000
+#define VALUE_PARAMEQ1_ST1_A1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST1_A1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST1_A1                           15
+#define FIXPT_PARAMEQ1_ST1_A1                          0x00000000
+#define VALUE_PARAMEQ1_ST1_A1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST1_A1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST2_B0                           16
+#define FIXPT_PARAMEQ1_ST2_B0                          0x00800000
+#define VALUE_PARAMEQ1_ST2_B0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_PARAMEQ1_ST2_B0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST2_B0                           16
+#define FIXPT_PARAMEQ1_ST2_B0                          0x00800000
+#define VALUE_PARAMEQ1_ST2_B0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_PARAMEQ1_ST2_B0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST2_B1                           17
+#define FIXPT_PARAMEQ1_ST2_B1                          0x00000000
+#define VALUE_PARAMEQ1_ST2_B1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST2_B1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST2_B1                           17
+#define FIXPT_PARAMEQ1_ST2_B1                          0x00000000
+#define VALUE_PARAMEQ1_ST2_B1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST2_B1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST2_B2                           18
+#define FIXPT_PARAMEQ1_ST2_B2                          0x00000000
+#define VALUE_PARAMEQ1_ST2_B2                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST2_B2                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST2_B2                           18
+#define FIXPT_PARAMEQ1_ST2_B2                          0x00000000
+#define VALUE_PARAMEQ1_ST2_B2                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST2_B2                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST2_A0                           19
+#define FIXPT_PARAMEQ1_ST2_A0                          0x00000000
+#define VALUE_PARAMEQ1_ST2_A0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST2_A0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST2_A0                           19
+#define FIXPT_PARAMEQ1_ST2_A0                          0x00000000
+#define VALUE_PARAMEQ1_ST2_A0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST2_A0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST2_A1                           20
+#define FIXPT_PARAMEQ1_ST2_A1                          0x00000000
+#define VALUE_PARAMEQ1_ST2_A1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST2_A1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST2_A1                           20
+#define FIXPT_PARAMEQ1_ST2_A1                          0x00000000
+#define VALUE_PARAMEQ1_ST2_A1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST2_A1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST3_B0                           21
+#define FIXPT_PARAMEQ1_ST3_B0                          0x00800000
+#define VALUE_PARAMEQ1_ST3_B0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_PARAMEQ1_ST3_B0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST3_B0                           21
+#define FIXPT_PARAMEQ1_ST3_B0                          0x00800000
+#define VALUE_PARAMEQ1_ST3_B0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_PARAMEQ1_ST3_B0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST3_B1                           22
+#define FIXPT_PARAMEQ1_ST3_B1                          0x00000000
+#define VALUE_PARAMEQ1_ST3_B1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST3_B1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST3_B1                           22
+#define FIXPT_PARAMEQ1_ST3_B1                          0x00000000
+#define VALUE_PARAMEQ1_ST3_B1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST3_B1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST3_B2                           23
+#define FIXPT_PARAMEQ1_ST3_B2                          0x00000000
+#define VALUE_PARAMEQ1_ST3_B2                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST3_B2                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST3_B2                           23
+#define FIXPT_PARAMEQ1_ST3_B2                          0x00000000
+#define VALUE_PARAMEQ1_ST3_B2                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST3_B2                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST3_A0                           24
+#define FIXPT_PARAMEQ1_ST3_A0                          0x00000000
+#define VALUE_PARAMEQ1_ST3_A0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST3_A0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST3_A0                           24
+#define FIXPT_PARAMEQ1_ST3_A0                          0x00000000
+#define VALUE_PARAMEQ1_ST3_A0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST3_A0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST3_A1                           25
+#define FIXPT_PARAMEQ1_ST3_A1                          0x00000000
+#define VALUE_PARAMEQ1_ST3_A1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST3_A1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST3_A1                           25
+#define FIXPT_PARAMEQ1_ST3_A1                          0x00000000
+#define VALUE_PARAMEQ1_ST3_A1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST3_A1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST4_B0                           26
+#define FIXPT_PARAMEQ1_ST4_B0                          0x00800000
+#define VALUE_PARAMEQ1_ST4_B0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_PARAMEQ1_ST4_B0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST4_B0                           26
+#define FIXPT_PARAMEQ1_ST4_B0                          0x00800000
+#define VALUE_PARAMEQ1_ST4_B0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_PARAMEQ1_ST4_B0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST4_B1                           27
+#define FIXPT_PARAMEQ1_ST4_B1                          0x00000000
+#define VALUE_PARAMEQ1_ST4_B1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST4_B1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST4_B1                           27
+#define FIXPT_PARAMEQ1_ST4_B1                          0x00000000
+#define VALUE_PARAMEQ1_ST4_B1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST4_B1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST4_B2                           28
+#define FIXPT_PARAMEQ1_ST4_B2                          0x00000000
+#define VALUE_PARAMEQ1_ST4_B2                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST4_B2                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST4_B2                           28
+#define FIXPT_PARAMEQ1_ST4_B2                          0x00000000
+#define VALUE_PARAMEQ1_ST4_B2                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST4_B2                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST4_A0                           29
+#define FIXPT_PARAMEQ1_ST4_A0                          0x00000000
+#define VALUE_PARAMEQ1_ST4_A0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST4_A0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST4_A0                           29
+#define FIXPT_PARAMEQ1_ST4_A0                          0x00000000
+#define VALUE_PARAMEQ1_ST4_A0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST4_A0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST4_A1                           30
+#define FIXPT_PARAMEQ1_ST4_A1                          0x00000000
+#define VALUE_PARAMEQ1_ST4_A1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST4_A1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST4_A1                           30
+#define FIXPT_PARAMEQ1_ST4_A1                          0x00000000
+#define VALUE_PARAMEQ1_ST4_A1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST4_A1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST5_B0                           31
+#define FIXPT_PARAMEQ1_ST5_B0                          0x00800000
+#define VALUE_PARAMEQ1_ST5_B0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_PARAMEQ1_ST5_B0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST5_B0                           31
+#define FIXPT_PARAMEQ1_ST5_B0                          0x00800000
+#define VALUE_PARAMEQ1_ST5_B0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_PARAMEQ1_ST5_B0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST5_B1                           32
+#define FIXPT_PARAMEQ1_ST5_B1                          0x00000000
+#define VALUE_PARAMEQ1_ST5_B1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST5_B1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST5_B1                           32
+#define FIXPT_PARAMEQ1_ST5_B1                          0x00000000
+#define VALUE_PARAMEQ1_ST5_B1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST5_B1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST5_B2                           33
+#define FIXPT_PARAMEQ1_ST5_B2                          0x00000000
+#define VALUE_PARAMEQ1_ST5_B2                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST5_B2                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST5_B2                           33
+#define FIXPT_PARAMEQ1_ST5_B2                          0x00000000
+#define VALUE_PARAMEQ1_ST5_B2                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST5_B2                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST5_A0                           34
+#define FIXPT_PARAMEQ1_ST5_A0                          0x00000000
+#define VALUE_PARAMEQ1_ST5_A0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST5_A0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST5_A0                           34
+#define FIXPT_PARAMEQ1_ST5_A0                          0x00000000
+#define VALUE_PARAMEQ1_ST5_A0                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST5_A0                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST5_A1                           35
+#define FIXPT_PARAMEQ1_ST5_A1                          0x00000000
+#define VALUE_PARAMEQ1_ST5_A1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST5_A1                           SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_PARAMEQ1_ST5_A1                           35
+#define FIXPT_PARAMEQ1_ST5_A1                          0x00000000
+#define VALUE_PARAMEQ1_ST5_A1                          SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0)
+#define TYPE_PARAMEQ1_ST5_A1                           SIGMASTUDIOTYPE_FIXPOINT
+
+/* Module Multiple 1 - Multiple Volume Control*/
+#define COUNT_MULTIPLE1                                2
+#define DEVICE_MULTIPLE1                               "IC1"
+#define ADDR_MULTIPLE1                                 36
+#define FIXPT_MULTIPLE1                                0x00800000
+#define VALUE_MULTIPLE1                                SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_MULTIPLE1                                 SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_MULTIPLE1_1                               37
+#define FIXPT_MULTIPLE1_1                              0x00800000
+#define VALUE_MULTIPLE1_1                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_MULTIPLE1_1                               SIGMASTUDIOTYPE_FIXPOINT
+
+/* Module Limiter 1 - Limiter*/
+#define COUNT_LIMITER1                                 15
+#define DEVICE_LIMITER1                                "IC1"
+#define ADDR_LIMITER1_S1                               38
+#define FIXPT_LIMITER1_S1                              0xFFFE2BE3
+#define VALUE_LIMITER1_S1                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(-0.01428571428571)
+#define TYPE_LIMITER1_S1                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_INT1                             39
+#define FIXPT_LIMITER1_INT1                            0x0022BE2B
+#define VALUE_LIMITER1_INT1                            SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.27142857142857)
+#define TYPE_LIMITER1_INT1                             SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_S2                               40
+#define FIXPT_LIMITER1_S2                              0xFFEAAAAB
+#define VALUE_LIMITER1_S2                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(-0.16666666666667)
+#define TYPE_LIMITER1_S2                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_INT2                             41
+#define FIXPT_LIMITER1_INT2                            0x006AAAAA
+#define VALUE_LIMITER1_INT2                            SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.8333333333333)
+#define TYPE_LIMITER1_INT2                             SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_S3                               42
+#define FIXPT_LIMITER1_S3                              0xFF9A69A7
+#define VALUE_LIMITER1_S3                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(-0.79365079365079)
+#define TYPE_LIMITER1_S3                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_INT3                             43
+#define FIXPT_LIMITER1_INT3                            0x00FDF7DF
+#define VALUE_LIMITER1_INT3                            SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1.98412698412698)
+#define TYPE_LIMITER1_INT3                             SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_S4                               44
+#define FIXPT_LIMITER1_S4                              0xF83C6C20
+#define VALUE_LIMITER1_S4                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(-15.527950310559)
+#define TYPE_LIMITER1_S4                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_INT4                             45
+#define FIXPT_LIMITER1_INT4                            0x03F5AA22
+#define VALUE_LIMITER1_INT4                            SIGMASTUDIOTYPE_FIXPOINT_CONVERT(7.91925465838509)
+#define TYPE_LIMITER1_INT4                             SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_C1                               46
+#define FIXPT_LIMITER1_C1                              0x01800000
+#define VALUE_LIMITER1_C1                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(3)
+#define TYPE_LIMITER1_C1                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_C2                               47
+#define FIXPT_LIMITER1_C2                              0x01000000
+#define VALUE_LIMITER1_C2                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(2)
+#define TYPE_LIMITER1_C2                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_C3                               48
+#define FIXPT_LIMITER1_C3                              0x00333333
+#define VALUE_LIMITER1_C3                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.4)
+#define TYPE_LIMITER1_C3                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_THRESHOLD                        49
+#define FIXPT_LIMITER1_THRESHOLD                       0x00800000
+#define VALUE_LIMITER1_THRESHOLD                       SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_LIMITER1_THRESHOLD                        SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_RMS                              50
+#define FIXPT_LIMITER1_RMS                             0x000007DC
+#define VALUE_LIMITER1_RMS                             SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.000239881380791562)
+#define TYPE_LIMITER1_RMS                              SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_DECAY                            51
+#define FIXPT_LIMITER1_DECAY                           0x00000800
+#define VALUE_LIMITER1_DECAY                           SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.000244140625)
+#define TYPE_LIMITER1_DECAY                            SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER1_DECAYCOMPLEMENT                  52
+#define FIXPT_LIMITER1_DECAYCOMPLEMENT                 0x007FF000
+#define VALUE_LIMITER1_DECAYCOMPLEMENT                 SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.99951171875)
+#define TYPE_LIMITER1_DECAYCOMPLEMENT                  SIGMASTUDIOTYPE_FIXPOINT
+
+/* Module Limiter 2 - Limiter*/
+#define COUNT_LIMITER2                                 15
+#define DEVICE_LIMITER2                                "IC1"
+#define ADDR_LIMITER2_S1                               53
+#define FIXPT_LIMITER2_S1                              0xFFFE2BE3
+#define VALUE_LIMITER2_S1                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(-0.01428571428571)
+#define TYPE_LIMITER2_S1                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_INT1                             54
+#define FIXPT_LIMITER2_INT1                            0x0022BE2B
+#define VALUE_LIMITER2_INT1                            SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.27142857142857)
+#define TYPE_LIMITER2_INT1                             SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_S2                               55
+#define FIXPT_LIMITER2_S2                              0xFFEAAAAB
+#define VALUE_LIMITER2_S2                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(-0.16666666666667)
+#define TYPE_LIMITER2_S2                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_INT2                             56
+#define FIXPT_LIMITER2_INT2                            0x006AAAAA
+#define VALUE_LIMITER2_INT2                            SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.8333333333333)
+#define TYPE_LIMITER2_INT2                             SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_S3                               57
+#define FIXPT_LIMITER2_S3                              0xFF9A69A7
+#define VALUE_LIMITER2_S3                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(-0.79365079365079)
+#define TYPE_LIMITER2_S3                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_INT3                             58
+#define FIXPT_LIMITER2_INT3                            0x00FDF7DF
+#define VALUE_LIMITER2_INT3                            SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1.98412698412698)
+#define TYPE_LIMITER2_INT3                             SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_S4                               59
+#define FIXPT_LIMITER2_S4                              0xF83C6C20
+#define VALUE_LIMITER2_S4                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(-15.527950310559)
+#define TYPE_LIMITER2_S4                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_INT4                             60
+#define FIXPT_LIMITER2_INT4                            0x03F5AA22
+#define VALUE_LIMITER2_INT4                            SIGMASTUDIOTYPE_FIXPOINT_CONVERT(7.91925465838509)
+#define TYPE_LIMITER2_INT4                             SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_C1                               61
+#define FIXPT_LIMITER2_C1                              0x01800000
+#define VALUE_LIMITER2_C1                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(3)
+#define TYPE_LIMITER2_C1                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_C2                               62
+#define FIXPT_LIMITER2_C2                              0x01000000
+#define VALUE_LIMITER2_C2                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(2)
+#define TYPE_LIMITER2_C2                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_C3                               63
+#define FIXPT_LIMITER2_C3                              0x00333333
+#define VALUE_LIMITER2_C3                              SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.4)
+#define TYPE_LIMITER2_C3                               SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_THRESHOLD                        64
+#define FIXPT_LIMITER2_THRESHOLD                       0x00800000
+#define VALUE_LIMITER2_THRESHOLD                       SIGMASTUDIOTYPE_FIXPOINT_CONVERT(1)
+#define TYPE_LIMITER2_THRESHOLD                        SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_RMS                              65
+#define FIXPT_LIMITER2_RMS                             0x000007DC
+#define VALUE_LIMITER2_RMS                             SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.000239881380791562)
+#define TYPE_LIMITER2_RMS                              SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_DECAY                            66
+#define FIXPT_LIMITER2_DECAY                           0x00000800
+#define VALUE_LIMITER2_DECAY                           SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.000244140625)
+#define TYPE_LIMITER2_DECAY                            SIGMASTUDIOTYPE_FIXPOINT
+#define ADDR_LIMITER2_DECAYCOMPLEMENT                  67
+#define FIXPT_LIMITER2_DECAYCOMPLEMENT                 0x007FF000
+#define VALUE_LIMITER2_DECAYCOMPLEMENT                 SIGMASTUDIOTYPE_FIXPOINT_CONVERT(0.99951171875)
+#define TYPE_LIMITER2_DECAYCOMPLEMENT                  SIGMASTUDIOTYPE_FIXPOINT
+
+#endif

Software/Firmware/ADAU1701-Firmware/DigiRadio_IC_1_REG.h

@@ -0,0 +1,565 @@
+/*
+ * File:           C:\Users\mikbi\Documents\Allegati\Desktop\DigiRadio\DigiRadio_IC_1_REG.h
+ *
+ * Created:        Monday, July 6, 2026 2:41:28 PM
+ * Description:    DigiRadio:IC 1 control register definitions.
+ *
+ * This software is distributed in the hope that it will be useful,
+ * but is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * This software may only be used to program products purchased from
+ * Analog Devices for incorporation by you into audio products that
+ * are intended for resale to audio product end users. This software
+ * may not be distributed whole or in any part to third parties.
+ *
+ * Copyright ©2026 Analog Devices, Inc. All rights reserved.
+ */
+#ifndef __DIGIRADIO_IC_1_REG_H__
+#define __DIGIRADIO_IC_1_REG_H__
+
+
+/* InterfaceRegister0  - Registers (IC 1) */
+#define REG_INTERFACEREGISTER0_IC_1_ADDR          0x800
+#define REG_INTERFACEREGISTER0_IC_1_BYTE          4
+#define REG_INTERFACEREGISTER0_IC_1_VALUE         0x0
+
+/* InterfaceRegister1  - Registers (IC 1) */
+#define REG_INTERFACEREGISTER1_IC_1_ADDR          0x801
+#define REG_INTERFACEREGISTER1_IC_1_BYTE          4
+#define REG_INTERFACEREGISTER1_IC_1_VALUE         0x0
+
+/* InterfaceRegister2  - Registers (IC 1) */
+#define REG_INTERFACEREGISTER2_IC_1_ADDR          0x802
+#define REG_INTERFACEREGISTER2_IC_1_BYTE          4
+#define REG_INTERFACEREGISTER2_IC_1_VALUE         0x0
+
+/* InterfaceRegister3  - Registers (IC 1) */
+#define REG_INTERFACEREGISTER3_IC_1_ADDR          0x803
+#define REG_INTERFACEREGISTER3_IC_1_BYTE          4
+#define REG_INTERFACEREGISTER3_IC_1_VALUE         0x0
+
+/* InterfaceRegister4  - Registers (IC 1) */
+#define REG_INTERFACEREGISTER4_IC_1_ADDR          0x804
+#define REG_INTERFACEREGISTER4_IC_1_BYTE          4
+#define REG_INTERFACEREGISTER4_IC_1_VALUE         0x0
+
+/* InterfaceRegister5  - Registers (IC 1) */
+#define REG_INTERFACEREGISTER5_IC_1_ADDR          0x805
+#define REG_INTERFACEREGISTER5_IC_1_BYTE          4
+#define REG_INTERFACEREGISTER5_IC_1_VALUE         0x0
+
+/* InterfaceRegister6  - Registers (IC 1) */
+#define REG_INTERFACEREGISTER6_IC_1_ADDR          0x806
+#define REG_INTERFACEREGISTER6_IC_1_BYTE          4
+#define REG_INTERFACEREGISTER6_IC_1_VALUE         0x0
+
+/* InterfaceRegister7  - Registers (IC 1) */
+#define REG_INTERFACEREGISTER7_IC_1_ADDR          0x807
+#define REG_INTERFACEREGISTER7_IC_1_BYTE          4
+#define REG_INTERFACEREGISTER7_IC_1_VALUE         0x0
+
+/* GpioAllRegister  - Registers (IC 1) */
+#define REG_GPIOALLREGISTER_IC_1_ADDR             0x808
+#define REG_GPIOALLREGISTER_IC_1_BYTE             2
+#define REG_GPIOALLREGISTER_IC_1_VALUE            0x0
+
+/* Adc0  - Registers (IC 1) */
+#define REG_ADC0_IC_1_ADDR                        0x809
+#define REG_ADC0_IC_1_BYTE                        1
+#define REG_ADC0_IC_1_VALUE                       0x0
+
+/* Adc1  - Registers (IC 1) */
+#define REG_ADC1_IC_1_ADDR                        0x80A
+#define REG_ADC1_IC_1_BYTE                        1
+#define REG_ADC1_IC_1_VALUE                       0x0
+
+/* Adc2  - Registers (IC 1) */
+#define REG_ADC2_IC_1_ADDR                        0x80B
+#define REG_ADC2_IC_1_BYTE                        1
+#define REG_ADC2_IC_1_VALUE                       0x0
+
+/* Adc3  - Registers (IC 1) */
+#define REG_ADC3_IC_1_ADDR                        0x80C
+#define REG_ADC3_IC_1_BYTE                        1
+#define REG_ADC3_IC_1_VALUE                       0x0
+
+/* CoreRegister  - Registers (IC 1) */
+#define REG_COREREGISTER_IC_1_ADDR                0x81C
+#define REG_COREREGISTER_IC_1_BYTE                2
+#define REG_COREREGISTER_IC_1_VALUE               0x1C
+
+/* RAMRegister  - Registers (IC 1) */
+#define REG_RAMREGISTER_IC_1_ADDR                 0x81D
+#define REG_RAMREGISTER_IC_1_BYTE                 1
+#define REG_RAMREGISTER_IC_1_VALUE                0x8
+
+/* SerialOutRegister1  - Registers (IC 1) */
+#define REG_SERIALOUTREGISTER1_IC_1_ADDR          0x81E
+#define REG_SERIALOUTREGISTER1_IC_1_BYTE          2
+#define REG_SERIALOUTREGISTER1_IC_1_VALUE         0x800
+
+/* SerialInputRegister  - Registers (IC 1) */
+#define REG_SERIALINPUTREGISTER_IC_1_ADDR         0x81F
+#define REG_SERIALINPUTREGISTER_IC_1_BYTE         1
+#define REG_SERIALINPUTREGISTER_IC_1_VALUE        0x0
+
+/* MpCfg0  - Registers (IC 1) */
+#define REG_MPCFG0_IC_1_ADDR                      0x820
+#define REG_MPCFG0_IC_1_BYTE                      3
+#define REG_MPCFG0_IC_1_VALUE                     0x440044
+
+/* MpCfg1  - Registers (IC 1) */
+#define REG_MPCFG1_IC_1_ADDR                      0x821
+#define REG_MPCFG1_IC_1_BYTE                      3
+#define REG_MPCFG1_IC_1_VALUE                     0x440004
+
+/* AnalogPowerDownRegister  - Registers (IC 1) */
+#define REG_ANALOGPOWERDOWNREGISTER_IC_1_ADDR     0x822
+#define REG_ANALOGPOWERDOWNREGISTER_IC_1_BYTE     2
+#define REG_ANALOGPOWERDOWNREGISTER_IC_1_VALUE    0x0
+
+/* TestRegister  - Registers (IC 1) */
+#define REG_TESTREGISTER_IC_1_ADDR                0x823
+#define REG_TESTREGISTER_IC_1_BYTE                2
+#define REG_TESTREGISTER_IC_1_VALUE               0x0
+
+/* AnalogInterfaceRegister0  - Registers (IC 1) */
+#define REG_ANALOGINTERFACEREGISTER0_IC_1_ADDR    0x824
+#define REG_ANALOGINTERFACEREGISTER0_IC_1_BYTE    2
+#define REG_ANALOGINTERFACEREGISTER0_IC_1_VALUE   0x8000
+
+/* AnalogInterfaceRegister1  - Registers (IC 1) */
+#define REG_ANALOGINTERFACEREGISTER1_IC_1_ADDR    0x825
+#define REG_ANALOGINTERFACEREGISTER1_IC_1_BYTE    2
+#define REG_ANALOGINTERFACEREGISTER1_IC_1_VALUE   0x0
+
+/* AnalogInterfaceRegister2  - Registers (IC 1) */
+#define REG_ANALOGINTERFACEREGISTER2_IC_1_ADDR    0x826
+#define REG_ANALOGINTERFACEREGISTER2_IC_1_BYTE    2
+#define REG_ANALOGINTERFACEREGISTER2_IC_1_VALUE   0x0
+
+/* AnalogInterfaceRegister3  - Registers (IC 1) */
+#define REG_ANALOGINTERFACEREGISTER3_IC_1_ADDR    0x827
+#define REG_ANALOGINTERFACEREGISTER3_IC_1_BYTE    2
+#define REG_ANALOGINTERFACEREGISTER3_IC_1_VALUE   0x1
+
+
+/*
+ *
+ * Control register's field descriptions
+ *
+ */
+
+/* InterfaceRegister0 (IC 1) */
+#define R0_INTERFACEREGISTER0_IC_1                0x00000000 /* 00000000000000000000000000000000b	[31:0] */
+#define R0_INTERFACEREGISTER0_IC_1_MASK           0xFFFFFFFF
+#define R0_INTERFACEREGISTER0_IC_1_SHIFT          0
+
+/* InterfaceRegister1 (IC 1) */
+#define R1_INTERFACEREGISTER1_IC_1                0x00000000 /* 00000000000000000000000000000000b	[31:0] */
+#define R1_INTERFACEREGISTER1_IC_1_MASK           0xFFFFFFFF
+#define R1_INTERFACEREGISTER1_IC_1_SHIFT          0
+
+/* InterfaceRegister2 (IC 1) */
+#define R2_INTERFACEREGISTER2_IC_1                0x00000000 /* 00000000000000000000000000000000b	[31:0] */
+#define R2_INTERFACEREGISTER2_IC_1_MASK           0xFFFFFFFF
+#define R2_INTERFACEREGISTER2_IC_1_SHIFT          0
+
+/* InterfaceRegister3 (IC 1) */
+#define R3_INTERFACEREGISTER3_IC_1                0x00000000 /* 00000000000000000000000000000000b	[31:0] */
+#define R3_INTERFACEREGISTER3_IC_1_MASK           0xFFFFFFFF
+#define R3_INTERFACEREGISTER3_IC_1_SHIFT          0
+
+/* InterfaceRegister4 (IC 1) */
+#define R4_INTERFACEREGISTER4_IC_1                0x00000000 /* 00000000000000000000000000000000b	[31:0] */
+#define R4_INTERFACEREGISTER4_IC_1_MASK           0xFFFFFFFF
+#define R4_INTERFACEREGISTER4_IC_1_SHIFT          0
+
+/* InterfaceRegister5 (IC 1) */
+#define R5_INTERFACEREGISTER5_IC_1                0x00000000 /* 00000000000000000000000000000000b	[31:0] */
+#define R5_INTERFACEREGISTER5_IC_1_MASK           0xFFFFFFFF
+#define R5_INTERFACEREGISTER5_IC_1_SHIFT          0
+
+/* InterfaceRegister6 (IC 1) */
+#define R6_INTERFACEREGISTER6_IC_1                0x00000000 /* 00000000000000000000000000000000b	[31:0] */
+#define R6_INTERFACEREGISTER6_IC_1_MASK           0xFFFFFFFF
+#define R6_INTERFACEREGISTER6_IC_1_SHIFT          0
+
+/* InterfaceRegister7 (IC 1) */
+#define R7_INTERFACEREGISTER7_IC_1                0x00000000 /* 00000000000000000000000000000000b	[31:0] */
+#define R7_INTERFACEREGISTER7_IC_1_MASK           0xFFFFFFFF
+#define R7_INTERFACEREGISTER7_IC_1_SHIFT          0
+
+/* GpioAllRegister (IC 1) */
+#define R8_PIN0_IC_1                              0x0    /* 0b	[0] */
+#define R8_PIN1_IC_1                              0x0    /* 0b	[1] */
+#define R8_PIN2_IC_1                              0x0    /* 0b	[2] */
+#define R8_PIN3_IC_1                              0x0    /* 0b	[3] */
+#define R8_PIN4_IC_1                              0x0    /* 0b	[4] */
+#define R8_PIN5_IC_1                              0x0    /* 0b	[5] */
+#define R8_PIN6_IC_1                              0x0    /* 0b	[6] */
+#define R8_PIN7_IC_1                              0x0    /* 0b	[7] */
+#define R8_PIN8_IC_1                              0x0    /* 0b	[8] */
+#define R8_PIN9_IC_1                              0x0    /* 0b	[9] */
+#define R8_PIN10_IC_1                             0x0    /* 0b	[10] */
+#define R8_PIN11_IC_1                             0x0    /* 0b	[11] */
+#define R8_PIN0_IC_1_MASK                         0x1
+#define R8_PIN0_IC_1_SHIFT                        0
+#define R8_PIN1_IC_1_MASK                         0x2
+#define R8_PIN1_IC_1_SHIFT                        1
+#define R8_PIN2_IC_1_MASK                         0x4
+#define R8_PIN2_IC_1_SHIFT                        2
+#define R8_PIN3_IC_1_MASK                         0x8
+#define R8_PIN3_IC_1_SHIFT                        3
+#define R8_PIN4_IC_1_MASK                         0x10
+#define R8_PIN4_IC_1_SHIFT                        4
+#define R8_PIN5_IC_1_MASK                         0x20
+#define R8_PIN5_IC_1_SHIFT                        5
+#define R8_PIN6_IC_1_MASK                         0x40
+#define R8_PIN6_IC_1_SHIFT                        6
+#define R8_PIN7_IC_1_MASK                         0x80
+#define R8_PIN7_IC_1_SHIFT                        7
+#define R8_PIN8_IC_1_MASK                         0x100
+#define R8_PIN8_IC_1_SHIFT                        8
+#define R8_PIN9_IC_1_MASK                         0x200
+#define R8_PIN9_IC_1_SHIFT                        9
+#define R8_PIN10_IC_1_MASK                        0x400
+#define R8_PIN10_IC_1_SHIFT                       10
+#define R8_PIN11_IC_1_MASK                        0x800
+#define R8_PIN11_IC_1_SHIFT                       11
+
+/* Adc0 (IC 1) */
+#define R9_ADC0_IC_1                              0x00   /* 00000000b	[7:0] */
+#define R9_ADC0_IC_1_MASK                         0xFF
+#define R9_ADC0_IC_1_SHIFT                        0
+
+/* Adc1 (IC 1) */
+#define R10_ADC1_IC_1                             0x00   /* 00000000b	[7:0] */
+#define R10_ADC1_IC_1_MASK                        0xFF
+#define R10_ADC1_IC_1_SHIFT                       0
+
+/* Adc2 (IC 1) */
+#define R11_ADC2_IC_1                             0x00   /* 00000000b	[7:0] */
+#define R11_ADC2_IC_1_MASK                        0xFF
+#define R11_ADC2_IC_1_SHIFT                       0
+
+/* Adc3 (IC 1) */
+#define R12_ADC3_IC_1                             0x00   /* 00000000b	[7:0] */
+#define R12_ADC3_IC_1_MASK                        0xFF
+#define R12_ADC3_IC_1_SHIFT                       0
+
+/* CoreRegister (IC 1) */
+#define R13_PROGRAM_LENGTH_IC_1                   0x0    /* 00b	[1:0] */
+#define R13_REGISTER_ZERO_IC_1                    0x1    /* 1b	[2] */
+#define R13_MUTE_DAC_IC_1                         0x1    /* 1b	[3] */
+#define R13_MUTE_ADC_IC_1                         0x1    /* 1b	[4] */
+#define R13_SAFELOAD_IC_1                         0x0    /* 0b	[5] */
+#define R13_WRITESPI_INTERFACEREG_IC_1            0x0    /* 0b	[6] */
+#define R13_WRITESPI_GPIO_IC_1                    0x0    /* 0b	[7] */
+#define R13_WRITESPI_ADC_IC_1                     0x0    /* 0b	[8] */
+#define R13_MUTE_SERIALIN_IC_1                    0x0    /* 0b	[9] */
+#define R13_GPIO_DEBOUNCE_IC_1                    0x0    /* 00b	[11:10] */
+#define R13_EXTMEM_SPEED_IC_1                     0x0    /* 00b	[13:12] */
+#define R13_PROGRAM_LENGTH_IC_1_MASK              0x3
+#define R13_PROGRAM_LENGTH_IC_1_SHIFT             0
+#define R13_REGISTER_ZERO_IC_1_MASK               0x4
+#define R13_REGISTER_ZERO_IC_1_SHIFT              2
+#define R13_MUTE_DAC_IC_1_MASK                    0x8
+#define R13_MUTE_DAC_IC_1_SHIFT                   3
+#define R13_MUTE_ADC_IC_1_MASK                    0x10
+#define R13_MUTE_ADC_IC_1_SHIFT                   4
+#define R13_SAFELOAD_IC_1_MASK                    0x20
+#define R13_SAFELOAD_IC_1_SHIFT                   5
+#define R13_WRITESPI_INTERFACEREG_IC_1_MASK       0x40
+#define R13_WRITESPI_INTERFACEREG_IC_1_SHIFT      6
+#define R13_WRITESPI_GPIO_IC_1_MASK               0x80
+#define R13_WRITESPI_GPIO_IC_1_SHIFT              7
+#define R13_WRITESPI_ADC_IC_1_MASK                0x100
+#define R13_WRITESPI_ADC_IC_1_SHIFT               8
+#define R13_MUTE_SERIALIN_IC_1_MASK               0x200
+#define R13_MUTE_SERIALIN_IC_1_SHIFT              9
+#define R13_GPIO_DEBOUNCE_IC_1_MASK               0xC00
+#define R13_GPIO_DEBOUNCE_IC_1_SHIFT              10
+#define R13_EXTMEM_SPEED_IC_1_MASK                0x3000
+#define R13_EXTMEM_SPEED_IC_1_SHIFT               12
+
+/* RAMRegister (IC 1) */
+#define R14_RAM_MODULO_IC_1                       0x8    /* 1000b	[3:0] */
+#define R14_RAM_MODULO_IC_1_MASK                  0xF
+#define R14_RAM_MODULO_IC_1_SHIFT                 0
+
+/* SerialOutRegister1 (IC 1) */
+#define R15_WORDLENGTH_IC_1                       0x0    /* 00b	[1:0] */
+#define R15_MSB_POS_IC_1                          0x0    /* 000b	[4:2] */
+#define R15_TDM_IC_1                              0x0    /* 0b	[5] */
+#define R15_FRAMESYNC_TYPE_IC_1                   0x0    /* 0b	[6] */
+#define R15_LRCLK_FREQ_IC_1                       0x0    /* 00b	[8:7] */
+#define R15_BCLK_FREQ_IC_1                        0x0    /* 00b	[10:9] */
+#define R15_MASTER_SLAVE_IC_1                     0x1    /* 1b	[11] */
+#define R15_BCLK_POLARITY_IC_1                    0x0    /* 0b	[12] */
+#define R15_LRCLK_POLARITY_IC_1                   0x0    /* 0b	[13] */
+#define R15_WORDLENGTH_IC_1_MASK                  0x3
+#define R15_WORDLENGTH_IC_1_SHIFT                 0
+#define R15_MSB_POS_IC_1_MASK                     0x1C
+#define R15_MSB_POS_IC_1_SHIFT                    2
+#define R15_TDM_IC_1_MASK                         0x20
+#define R15_TDM_IC_1_SHIFT                        5
+#define R15_FRAMESYNC_TYPE_IC_1_MASK              0x40
+#define R15_FRAMESYNC_TYPE_IC_1_SHIFT             6
+#define R15_LRCLK_FREQ_IC_1_MASK                  0x180
+#define R15_LRCLK_FREQ_IC_1_SHIFT                 7
+#define R15_BCLK_FREQ_IC_1_MASK                   0x600
+#define R15_BCLK_FREQ_IC_1_SHIFT                  9
+#define R15_MASTER_SLAVE_IC_1_MASK                0x800
+#define R15_MASTER_SLAVE_IC_1_SHIFT               11
+#define R15_BCLK_POLARITY_IC_1_MASK               0x1000
+#define R15_BCLK_POLARITY_IC_1_SHIFT              12
+#define R15_LRCLK_POLARITY_IC_1_MASK              0x2000
+#define R15_LRCLK_POLARITY_IC_1_SHIFT             13
+
+/* SerialInputRegister (IC 1) */
+#define R16_INPUT_MODE_IC_1                       0x0    /* 000b	[2:0] */
+#define R16_BCLK_POLARITY_IC_1                    0x0    /* 0b	[3] */
+#define R16_LRCLK_POLARITY_IC_1                   0x0    /* 0b	[4] */
+#define R16_INPUT_MODE_IC_1_MASK                  0x7
+#define R16_INPUT_MODE_IC_1_SHIFT                 0
+#define R16_BCLK_POLARITY_IC_1_MASK               0x8
+#define R16_BCLK_POLARITY_IC_1_SHIFT              3
+#define R16_LRCLK_POLARITY_IC_1_MASK              0x10
+#define R16_LRCLK_POLARITY_IC_1_SHIFT             4
+
+/* MpCfg0 (IC 1) */
+#define R17_MFSELECT0_IC_1                        0x4    /* 100b	[2:0] */
+#define R17_MFINVERT0_IC_1                        0x0    /* 0b	[3] */
+#define R17_MFSELECT1_IC_1                        0x4    /* 100b	[6:4] */
+#define R17_MFINVERT1_IC_1                        0x0    /* 0b	[7] */
+#define R17_MFSELECT2_IC_1                        0x0    /* 000b	[10:8] */
+#define R17_MFINVERT2_IC_1                        0x0    /* 0b	[11] */
+#define R17_MFSELECT3_IC_1                        0x0    /* 000b	[14:12] */
+#define R17_MFINVERT3_IC_1                        0x0    /* 0b	[15] */
+#define R17_MFSELECT4_IC_1                        0x4    /* 100b	[18:16] */
+#define R17_MFINVERT4_IC_1                        0x0    /* 0b	[19] */
+#define R17_MFSELECT5_IC_1                        0x4    /* 100b	[22:20] */
+#define R17_MFINVERT5_IC_1                        0x0    /* 0b	[23] */
+#define R17_MFSELECT0_IC_1_MASK                   0x7
+#define R17_MFSELECT0_IC_1_SHIFT                  0
+#define R17_MFINVERT0_IC_1_MASK                   0x8
+#define R17_MFINVERT0_IC_1_SHIFT                  3
+#define R17_MFSELECT1_IC_1_MASK                   0x70
+#define R17_MFSELECT1_IC_1_SHIFT                  4
+#define R17_MFINVERT1_IC_1_MASK                   0x80
+#define R17_MFINVERT1_IC_1_SHIFT                  7
+#define R17_MFSELECT2_IC_1_MASK                   0x700
+#define R17_MFSELECT2_IC_1_SHIFT                  8
+#define R17_MFINVERT2_IC_1_MASK                   0x800
+#define R17_MFINVERT2_IC_1_SHIFT                  11
+#define R17_MFSELECT3_IC_1_MASK                   0x7000
+#define R17_MFSELECT3_IC_1_SHIFT                  12
+#define R17_MFINVERT3_IC_1_MASK                   0x8000
+#define R17_MFINVERT3_IC_1_SHIFT                  15
+#define R17_MFSELECT4_IC_1_MASK                   0x70000
+#define R17_MFSELECT4_IC_1_SHIFT                  16
+#define R17_MFINVERT4_IC_1_MASK                   0x80000
+#define R17_MFINVERT4_IC_1_SHIFT                  19
+#define R17_MFSELECT5_IC_1_MASK                   0x700000
+#define R17_MFSELECT5_IC_1_SHIFT                  20
+#define R17_MFINVERT5_IC_1_MASK                   0x800000
+#define R17_MFINVERT5_IC_1_SHIFT                  23
+
+/* MpCfg1 (IC 1) */
+#define R18_MFSELECT6_IC_1                        0x4    /* 100b	[2:0] */
+#define R18_MFINVERT6_IC_1                        0x0    /* 0b	[3] */
+#define R18_MFSELECT7_IC_1                        0x0    /* 000b	[6:4] */
+#define R18_MFINVERT7_IC_1                        0x0    /* 0b	[7] */
+#define R18_MFSELECT8_IC_1                        0x0    /* 000b	[10:8] */
+#define R18_MFINVERT8_IC_1                        0x0    /* 0b	[11] */
+#define R18_MFSELECT9_IC_1                        0x0    /* 000b	[14:12] */
+#define R18_MFINVERT9_IC_1                        0x0    /* 0b	[15] */
+#define R18_MFSELECT10_IC_1                       0x4    /* 100b	[18:16] */
+#define R18_MFINVERT10_IC_1                       0x0    /* 0b	[19] */
+#define R18_MFSELECT11_IC_1                       0x4    /* 100b	[22:20] */
+#define R18_MFINVERT11_IC_1                       0x0    /* 0b	[23] */
+#define R18_MFSELECT6_IC_1_MASK                   0x7
+#define R18_MFSELECT6_IC_1_SHIFT                  0
+#define R18_MFINVERT6_IC_1_MASK                   0x8
+#define R18_MFINVERT6_IC_1_SHIFT                  3
+#define R18_MFSELECT7_IC_1_MASK                   0x70
+#define R18_MFSELECT7_IC_1_SHIFT                  4
+#define R18_MFINVERT7_IC_1_MASK                   0x80
+#define R18_MFINVERT7_IC_1_SHIFT                  7
+#define R18_MFSELECT8_IC_1_MASK                   0x700
+#define R18_MFSELECT8_IC_1_SHIFT                  8
+#define R18_MFINVERT8_IC_1_MASK                   0x800
+#define R18_MFINVERT8_IC_1_SHIFT                  11
+#define R18_MFSELECT9_IC_1_MASK                   0x7000
+#define R18_MFSELECT9_IC_1_SHIFT                  12
+#define R18_MFINVERT9_IC_1_MASK                   0x8000
+#define R18_MFINVERT9_IC_1_SHIFT                  15
+#define R18_MFSELECT10_IC_1_MASK                  0x70000
+#define R18_MFSELECT10_IC_1_SHIFT                 16
+#define R18_MFINVERT10_IC_1_MASK                  0x80000
+#define R18_MFINVERT10_IC_1_SHIFT                 19
+#define R18_MFSELECT11_IC_1_MASK                  0x700000
+#define R18_MFSELECT11_IC_1_SHIFT                 20
+#define R18_MFINVERT11_IC_1_MASK                  0x800000
+#define R18_MFINVERT11_IC_1_SHIFT                 23
+
+/* AnalogPowerDownRegister (IC 1) */
+#define R19_DAC3_POWERDOWN_IC_1                   0x0    /* 0b	[0] */
+#define R19_DAC2_POWERDOWN_IC_1                   0x0    /* 0b	[1] */
+#define R19_DAC1_POWERDOWN_IC_1                   0x0    /* 0b	[2] */
+#define R19_DAC0_POWERDOWN_IC_1                   0x0    /* 0b	[3] */
+#define R19_DACS_RESET_IC_1                       0x0    /* 0b	[4] */
+#define R19_REF_CORE_POWERDOWN_IC_1               0x0    /* 0b	[5] */
+#define R19_REF_BUF_POWERDOWN_IC_1                0x0    /* 0b	[6] */
+#define R19_ADCS_POWERDOWN_IC_1                   0x0    /* 0b	[7] */
+#define R19_AUX_ADC_FILTER_IC_1                   0x0    /* 000b	[10:8] */
+#define R19_DAC3_POWERDOWN_IC_1_MASK              0x1
+#define R19_DAC3_POWERDOWN_IC_1_SHIFT             0
+#define R19_DAC2_POWERDOWN_IC_1_MASK              0x2
+#define R19_DAC2_POWERDOWN_IC_1_SHIFT             1
+#define R19_DAC1_POWERDOWN_IC_1_MASK              0x4
+#define R19_DAC1_POWERDOWN_IC_1_SHIFT             2
+#define R19_DAC0_POWERDOWN_IC_1_MASK              0x8
+#define R19_DAC0_POWERDOWN_IC_1_SHIFT             3
+#define R19_DACS_RESET_IC_1_MASK                  0x10
+#define R19_DACS_RESET_IC_1_SHIFT                 4
+#define R19_REF_CORE_POWERDOWN_IC_1_MASK          0x20
+#define R19_REF_CORE_POWERDOWN_IC_1_SHIFT         5
+#define R19_REF_BUF_POWERDOWN_IC_1_MASK           0x40
+#define R19_REF_BUF_POWERDOWN_IC_1_SHIFT          6
+#define R19_ADCS_POWERDOWN_IC_1_MASK              0x80
+#define R19_ADCS_POWERDOWN_IC_1_SHIFT             7
+#define R19_AUX_ADC_FILTER_IC_1_MASK              0x700
+#define R19_AUX_ADC_FILTER_IC_1_SHIFT             8
+
+/* TestRegister (IC 1) */
+#define R20_ADCCLOCKDELAY_IC_1                    0x0    /* 000b	[2:0] */
+#define R20_ADCSYNCFILTL_SDATAA_D_IC_1            0x0    /* 0b	[3] */
+#define R20_ADCSYNCFILTR_SDATAA_D_IC_1            0x0    /* 0b	[4] */
+#define R20_SPIKEFILT_SEROUT0_1_IC_1              0x0    /* 0b	[5] */
+#define R20_UNUSED_IC_1                           0x00   /* 0000000000b	[15:6] */
+#define R20_ADCCLOCKDELAY_IC_1_MASK               0x7
+#define R20_ADCCLOCKDELAY_IC_1_SHIFT              0
+#define R20_ADCSYNCFILTL_SDATAA_D_IC_1_MASK       0x8
+#define R20_ADCSYNCFILTL_SDATAA_D_IC_1_SHIFT      3
+#define R20_ADCSYNCFILTR_SDATAA_D_IC_1_MASK       0x10
+#define R20_ADCSYNCFILTR_SDATAA_D_IC_1_SHIFT      4
+#define R20_SPIKEFILT_SEROUT0_1_IC_1_MASK         0x20
+#define R20_SPIKEFILT_SEROUT0_1_IC_1_SHIFT        5
+#define R20_UNUSED_IC_1_MASK                      0xFFC0
+#define R20_UNUSED_IC_1_SHIFT                     6
+
+/* AnalogInterfaceRegister0 (IC 1) */
+#define R21_CHOP_ENB_INT_AMP_IC_1                 0x0    /* 0b	[0] */
+#define R21_PD_INT_AMP_IC_1                       0x0    /* 0b	[1] */
+#define R21_ADC_NON_OVERLAP_ADJ_IC_1              0x0    /* 0b	[2] */
+#define R21_ADC_I_SEL_IC_1                        0x0    /* 00000b	[7:3] */
+#define R21_ADC_CLK_ADJ_IC_1                      0x0    /* 000b	[10:8] */
+#define R21_LCHOP_PMOS_CTRL_IC_1                  0x0    /* 00b	[12:11] */
+#define R21_LCHOP_AMP_ENB_IC_1                    0x0    /* 0b	[13] */
+#define R21_LSCRAM_ENB_IC_1                       0x0    /* 0b	[14] */
+#define R21_AUX_ADC_EN_IC_1                       0x1    /* 1b	[15] */
+#define R21_CHOP_ENB_INT_AMP_IC_1_MASK            0x1
+#define R21_CHOP_ENB_INT_AMP_IC_1_SHIFT           0
+#define R21_PD_INT_AMP_IC_1_MASK                  0x2
+#define R21_PD_INT_AMP_IC_1_SHIFT                 1
+#define R21_ADC_NON_OVERLAP_ADJ_IC_1_MASK         0x4
+#define R21_ADC_NON_OVERLAP_ADJ_IC_1_SHIFT        2
+#define R21_ADC_I_SEL_IC_1_MASK                   0xF8
+#define R21_ADC_I_SEL_IC_1_SHIFT                  3
+#define R21_ADC_CLK_ADJ_IC_1_MASK                 0x700
+#define R21_ADC_CLK_ADJ_IC_1_SHIFT                8
+#define R21_LCHOP_PMOS_CTRL_IC_1_MASK             0x1800
+#define R21_LCHOP_PMOS_CTRL_IC_1_SHIFT            11
+#define R21_LCHOP_AMP_ENB_IC_1_MASK               0x2000
+#define R21_LCHOP_AMP_ENB_IC_1_SHIFT              13
+#define R21_LSCRAM_ENB_IC_1_MASK                  0x4000
+#define R21_LSCRAM_ENB_IC_1_SHIFT                 14
+#define R21_AUX_ADC_EN_IC_1_MASK                  0x8000
+#define R21_AUX_ADC_EN_IC_1_SHIFT                 15
+
+/* AnalogInterfaceRegister1 (IC 1) */
+#define R22_RSWC_DAC_CTRL_IC_1                    0x0    /* 00b	[1:0] */
+#define R22_RCLK_SEL_PMOS_IC_1                    0x0    /* 00b	[3:2] */
+#define R22_RCLK_SEL_AMP_IC_1                     0x0    /* 00b	[5:4] */
+#define R22_RCHOP_PMOS_CTRL_IC_1                  0x0    /* 00b	[7:6] */
+#define R22_LCLK_SEL_PMOS_IC_1                    0x0    /* 00b	[9:8] */
+#define R22_LSWC_DAC_CTRL_IC_1                    0x0    /* 00b	[11:10] */
+#define R22_CLK_SEL_INT_AMP_IC_1                  0x0    /* 00b	[13:12] */
+#define R22_RSWC_DAC_CTRL_IC_1_MASK               0x3
+#define R22_RSWC_DAC_CTRL_IC_1_SHIFT              0
+#define R22_RCLK_SEL_PMOS_IC_1_MASK               0xC
+#define R22_RCLK_SEL_PMOS_IC_1_SHIFT              2
+#define R22_RCLK_SEL_AMP_IC_1_MASK                0x30
+#define R22_RCLK_SEL_AMP_IC_1_SHIFT               4
+#define R22_RCHOP_PMOS_CTRL_IC_1_MASK             0xC0
+#define R22_RCHOP_PMOS_CTRL_IC_1_SHIFT            6
+#define R22_LCLK_SEL_PMOS_IC_1_MASK               0x300
+#define R22_LCLK_SEL_PMOS_IC_1_SHIFT              8
+#define R22_LSWC_DAC_CTRL_IC_1_MASK               0xC00
+#define R22_LSWC_DAC_CTRL_IC_1_SHIFT              10
+#define R22_CLK_SEL_INT_AMP_IC_1_MASK             0x3000
+#define R22_CLK_SEL_INT_AMP_IC_1_SHIFT            12
+
+/* AnalogInterfaceRegister2 (IC 1) */
+#define R23_UNUSED_IC_1                           0x0    /* 0b	[0] */
+#define R23_ADC_DITHER_EN_IC_1                    0x0    /* 0b	[1] */
+#define R23_XTAL_ENB_IC_1                         0x0    /* 0b	[2] */
+#define R23_PLL_PD_IC_1                           0x0    /* 0b	[3] */
+#define R23_IBIAS_TO_PIN_IC_1                     0x0    /* 0b	[4] */
+#define R23_IBIAS_ADJ_IC_1                        0x0    /* 0000b	[8:5] */
+#define R23_VREF_TRIM_IC_1                        0x0    /* 0000b	[12:9] */
+#define R23_REF_I_SEL_IC_1                        0x0    /* 0b	[13] */
+#define R23_RSCRAM_ENB_IC_1                       0x0    /* 0b	[14] */
+#define R23_LCHOP_AMP_ENB_IC_1                    0x0    /* 0b	[15] */
+#define R23_UNUSED_IC_1_MASK                      0x1
+#define R23_UNUSED_IC_1_SHIFT                     0
+#define R23_ADC_DITHER_EN_IC_1_MASK               0x2
+#define R23_ADC_DITHER_EN_IC_1_SHIFT              1
+#define R23_XTAL_ENB_IC_1_MASK                    0x4
+#define R23_XTAL_ENB_IC_1_SHIFT                   2
+#define R23_PLL_PD_IC_1_MASK                      0x8
+#define R23_PLL_PD_IC_1_SHIFT                     3
+#define R23_IBIAS_TO_PIN_IC_1_MASK                0x10
+#define R23_IBIAS_TO_PIN_IC_1_SHIFT               4
+#define R23_IBIAS_ADJ_IC_1_MASK                   0x1E0
+#define R23_IBIAS_ADJ_IC_1_SHIFT                  5
+#define R23_VREF_TRIM_IC_1_MASK                   0x1E00
+#define R23_VREF_TRIM_IC_1_SHIFT                  9
+#define R23_REF_I_SEL_IC_1_MASK                   0x2000
+#define R23_REF_I_SEL_IC_1_SHIFT                  13
+#define R23_RSCRAM_ENB_IC_1_MASK                  0x4000
+#define R23_RSCRAM_ENB_IC_1_SHIFT                 14
+#define R23_LCHOP_AMP_ENB_IC_1_MASK               0x8000
+#define R23_LCHOP_AMP_ENB_IC_1_SHIFT              15
+
+/* AnalogInterfaceRegister3 (IC 1) */
+#define R24_DAC_OFFSET_IC_1                       0x1    /* 01b	[1:0] */
+#define R24_DAC_DITHER_ENABLE_IC_1                0x0    /* 0b	[2] */
+#define R24_PCTRL_IC_1                            0x0    /* 00b	[4:3] */
+#define R24_DAC_PCLK_SEL_IC_1                     0x0    /* 00b	[6:5] */
+#define R24_DAC_I_SEL_IC_1                        0x0    /* 0000b	[10:7] */
+#define R24_DAC_CLK_SEL_IC_1                      0x0    /* 00b	[12:11] */
+#define R24_DAC_CHOP_ENB_IC_1                     0x0    /* 0b	[13] */
+#define R24_DAC_DRTZ_IC_1                         0x0    /* 00b	[15:14] */
+#define R24_DAC_OFFSET_IC_1_MASK                  0x3
+#define R24_DAC_OFFSET_IC_1_SHIFT                 0
+#define R24_DAC_DITHER_ENABLE_IC_1_MASK           0x4
+#define R24_DAC_DITHER_ENABLE_IC_1_SHIFT          2
+#define R24_PCTRL_IC_1_MASK                       0x18
+#define R24_PCTRL_IC_1_SHIFT                      3
+#define R24_DAC_PCLK_SEL_IC_1_MASK                0x60
+#define R24_DAC_PCLK_SEL_IC_1_SHIFT               5
+#define R24_DAC_I_SEL_IC_1_MASK                   0x780
+#define R24_DAC_I_SEL_IC_1_SHIFT                  7
+#define R24_DAC_CLK_SEL_IC_1_MASK                 0x1800
+#define R24_DAC_CLK_SEL_IC_1_SHIFT                11
+#define R24_DAC_CHOP_ENB_IC_1_MASK                0x2000
+#define R24_DAC_CHOP_ENB_IC_1_SHIFT               13
+#define R24_DAC_DRTZ_IC_1_MASK                    0xC000
+#define R24_DAC_DRTZ_IC_1_SHIFT                   14
+
+#endif

Software/Firmware/ADAU1701-Firmware/DigiRadio_NetList.xml

@@ -0,0 +1,80 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- *
+ * This software is distributed in the hope that it will be useful,
+ * but is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * This software may only be used to program products purchased from
+ * Analog Devices for incorporation by you into audio products that
+ * are intended for resale to audio product end users. This software
+ * may not be distributed whole or in any part to third parties.
+ *
+ * Copyright © 2026 Analog Devices, Inc. All rights reserved.
+ */
+-->
+<!--NetList XML file-->
+<NetList>
+    <IC name=" IC 1 " type="DSPSigma100">
+        <Schematic>
+            <Algorithm name="ICSigma100In1" friendlyname="170x\140x input " cell="Input1 " location="{X=-15, Y=104} " Growth="10 " GrowthB="0 " FS="48000">
+                <Link pin="O_C33_A0_P3_out" dir="out" link="Link0" />
+                <Link pin="O_C33_A0_P4_out" dir="out" link="Link1" />
+                <Link pin="O_C33_A0_P5_out" dir="out" link="Link2" />
+                <Link pin="O_C33_A0_P6_out" dir="out" link="Link3" />
+            </Algorithm>
+            <Algorithm name="Gain1940AlgNS1" friendlyname="Gain (no slew) " cell="Si4674 " location="{X=168, Y=5} " Growth="0 " GrowthB="0">
+                <Link pin="I_C63_A0_P1_in" dir="in" link="Link0" />
+                <Link pin="O_C63_A0_P2_out" dir="out" link="Link4" />
+            </Algorithm>
+            <Algorithm name="Gain1940AlgNS2" friendlyname="Gain (no slew) " cell="Si4674 " location="{X=168, Y=5} " Growth="0 " GrowthB="0">
+                <Link pin="I_C63_A1_P1_in" dir="in" link="Link1" />
+                <Link pin="O_C63_A1_P2_out" dir="out" link="Link5" />
+            </Algorithm>
+            <Algorithm name="Gain1940AlgNS3" friendlyname="Gain (no slew) " cell="ESP32 " location="{X=166, Y=196} " Growth="0 " GrowthB="0">
+                <Link pin="I_C75_A0_P1_in" dir="in" link="Link2" />
+                <Link pin="O_C75_A0_P2_out" dir="out" link="Link6" />
+            </Algorithm>
+            <Algorithm name="Gain1940AlgNS4" friendlyname="Gain (no slew) " cell="ESP32 " location="{X=166, Y=196} " Growth="0 " GrowthB="0">
+                <Link pin="I_C75_A1_P1_in" dir="in" link="Link3" />
+                <Link pin="O_C75_A1_P2_out" dir="out" link="Link7" />
+            </Algorithm>
+            <Algorithm name="StereoMixerAlg1" friendlyname="Stereo Mixer " cell="St Mixer1 " location="{X=381, Y=115} " Growth="2 " GrowthB="0">
+                <Link pin="I_C84_A0_P3_in" dir="in" link="Link4" />
+                <Link pin="I_C84_A0_P4_in" dir="in" link="Link5" />
+                <Link pin="I_C84_A0_P5_in" dir="in" link="Link6" />
+                <Link pin="I_C84_A0_P6_in" dir="in" link="Link7" />
+                <Link pin="O_C84_A0_P1_out" dir="out" link="Link8" />
+                <Link pin="O_C84_A0_P2_out" dir="out" link="Link9" />
+            </Algorithm>
+            <Algorithm name="PEQ1Chan1" friendlyname="PEQ1Chan - Double Precision " cell="Param EQ1 " location="{X=502, Y=156} " Growth="2 " GrowthB="0">
+                <Link pin="I_C125_A0_P1_in" dir="in" link="Link8" />
+                <Link pin="I_C125_A0_P3_in" dir="in" link="Link9" />
+                <Link pin="O_C125_A0_P2_out" dir="out" link="Link10" />
+                <Link pin="O_C125_A0_P4_out" dir="out" link="Link11" />
+            </Algorithm>
+            <Algorithm name="Gain1940AlgNS5" friendlyname="Gain (no slew) " cell="Multiple 1 " location="{X=628, Y=88} " Growth="0 " GrowthB="0">
+                <Link pin="I_C138_A0_P1_in" dir="in" link="Link10" />
+                <Link pin="O_C138_A0_P2_out" dir="out" link="Link12" />
+            </Algorithm>
+            <Algorithm name="Gain1940AlgNS6" friendlyname="Gain (no slew) " cell="Multiple 1 " location="{X=628, Y=88} " Growth="0 " GrowthB="0">
+                <Link pin="I_C138_A1_P1_in" dir="in" link="Link11" />
+                <Link pin="O_C138_A1_P2_out" dir="out" link="Link13" />
+            </Algorithm>
+            <Algorithm name="limiterAlg1" friendlyname="Limiter with Indicator " cell="Limiter 1 " location="{X=761, Y=40} " Growth="0 " GrowthB="0">
+                <Link pin="I_C169_A0_P1_in" dir="in" link="Link12" />
+                <Link pin="O_C169_A0_P2_out" dir="out" link="Link15" />
+            </Algorithm>
+            <Algorithm name="limiterAlg2" friendlyname="Limiter with Indicator " cell="Limiter 2 " location="{X=765, Y=189} " Growth="0 " GrowthB="0">
+                <Link pin="I_C174_A0_P1_in" dir="in" link="Link13" />
+                <Link pin="O_C174_A0_P2_out" dir="out" link="Link14" />
+            </Algorithm>
+            <Algorithm name="ICSigma100Out2" friendlyname="170x\140x output " cell="Output2 " location="{X=890, Y=227} " Growth="0 " GrowthB="0">
+                <Link pin="I_C185_A0_P1_in" dir="in" link="Link14" />
+            </Algorithm>
+            <Algorithm name="ICSigma100Out1" friendlyname="170x\140x output " cell="Output1 " location="{X=877, Y=57} " Growth="0 " GrowthB="0">
+                <Link pin="I_C183_A0_P1_in" dir="in" link="Link15" />
+            </Algorithm>
+        </Schematic>
+    </IC>
+</NetList>

Software/Firmware/ADAU1701-Firmware/NumBytes_IC_1.dat

@@ -0,0 +1,5 @@
+4,
+5122,
+4098,
+26,
+4,

Software/Firmware/ADAU1701-Firmware/README.md

@@ -0,0 +1,13 @@
+# ADAU1701 SigmaStudio export
+
+SigmaStudio project **DigiRadio**, IC1 = ADAU1701.
+
+Key files:
+- `DigiRadio_IC_1.h` — program/param RAM data + `default_download_IC_1()`
+- `DigiRadio_IC_1_REG.h` — register map
+- `DigiRadio_IC_1_PARAM.h` — parameter handles (safeload, Slice 5+)
+
+The ESP32 replays `default_download_IC_1()` over I2C on every boot via
+`adau1701::Adau1701Driver` (see `components/drivers/adau1701/`).
+
+I2C address: 7-bit `0x34` (ADDR0=ADDR1=GND), matching `board_pins.hpp`.

Software/Firmware/ADAU1701-Firmware/SigmaStudioFW.h

@@ -0,0 +1,54 @@
+/**
+ * @file    SigmaStudioFW.h
+ * @brief   Minimal SigmaStudio download helpers for ADAU1701 RAM boot.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Subset of the Analog Devices SigmaStudio export support library.
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef unsigned char ADI_REG_TYPE;
+
+/**
+ * @brief    Bind the I2C port used by SIGMA_WRITE_REGISTER_BLOCK.
+ *
+ * @param    port       ESP-IDF I2C master port number.
+ * @param    addr7      ADAU1701 7-bit I2C address (0x34 on DigiRadio).
+ */
+void sigma_studio_bind_i2c(int port, unsigned char addr7);
+
+/** @brief Attach the I2C device handle created by Adau1701Driver. */
+void sigma_studio_set_device(void* i2cDevHandle);
+
+/**
+ * @brief    Write a contiguous register/data block to the ADAU1701.
+ *
+ * @param    devAddress  SigmaStudio device address (0x68 write addr).
+ * @param    address     16-bit target address in DSP memory map.
+ * @param    length      Payload length in bytes.
+ * @param    pData       Payload bytes.
+ */
+void SIGMA_WRITE_REGISTER_BLOCK(unsigned char devAddress,
+                                unsigned int address,
+                                unsigned char length,
+                                ADI_REG_TYPE* pData);
+
+/**
+ * @brief    Run the DigiRadio SigmaStudio default download sequence.
+ */
+void adau1701_run_default_download(void);
+
+#ifdef __cplusplus
+}
+#endif

Software/Firmware/ADAU1701-Firmware/defines.h

@@ -0,0 +1,26 @@
+/*
+ * File:           defines.h
+ *
+ * Created:        Monday, July 6, 2026 2:41:28 PM
+ * Description:    DigiRadio IC default download data definitions.
+ *
+ * This software is distributed in the hope that it will be useful,
+ * but is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * This software may only be used to program products purchased from
+ * Analog Devices for incorporation by you into audio products that
+ * are intended for resale to audio product end users. This software
+ * may not be distributed whole or in any part to third parties.
+ *
+ * Copyright ©2026 Analog Devices, Inc. All rights reserved.
+ */
+#ifndef __DEFINES_H__
+#define __DEFINES_H__
+
+#define BufferSize_IC_1     	9254
+#define NumTransactions_IC_1	5
+
+
+#endif

Software/Firmware/README.md

@@ -0,0 +1,20 @@
+# DigiRadio — companion-chip firmware assets
+
+Binary and SigmaStudio exports loaded by the ESP32 at every boot.
+
+| Directory | Chip | Contents |
+|-----------|------|----------|
+| `ADAU1701-Firmware/` | ADAU1701 SigmaDSP | SigmaStudio export (`DigiRadio_IC_1.h`, …) — RAM program |
+| `Si4684-Firmware/` | Si4684 DAB+/FM tuner | ROM patch + DAB + FM application images (`.bin`) |
+
+## Si4684 blobs
+
+`rom_patch_016.bin` and `dab_firmware.bin` are extracted from the
+[PE5PVB SI4684-DAB-Receiver](https://github.com/PE5PVB/SI4684-DAB-Receiver)
+project. `fm_firmware.bin` comes from the Skyworks Si4684 eval firmware pack
+(see `tools/fetch_si4684_firmware.py --si46xx-dir`).
+
+## ADAU1701 export
+
+Generated by Analog Devices SigmaStudio for the DigiRadio DSP schematic.
+Loaded on every boot (no self-boot EEPROM on this board).

Software/Firmware/Si4684-Firmware/README.md

@@ -0,0 +1,43 @@
+# Si4684 firmware images
+
+| File | Size (typ.) | Role |
+|------|-------------|------|
+| `rom_patch_016.bin` | 5796 | ROM patch / bootloader helper (HOST_LOAD before main image) |
+| `dab_firmware.bin` | ~517 KB | DAB+ application image (PE5PVB / Skyworks BIF) |
+| `fm_firmware.bin` | ~530 KB | FM application image (Skyworks `fm_radio_5_1_0.bin`, AN649 A10) |
+
+Boot sequence: AN649 — POWER_UP → LOAD_INIT → HOST_LOAD(patch) → LOAD_INIT →
+HOST_LOAD(image) → BOOT. DAB and FM use the same patch; only the application
+image differs.
+
+## Refresh blobs
+
+```bash
+# DAB + patch from PE5PVB GitHub (always safe to re-run):
+python3 tools/fetch_si4684_firmware.py --dab-only
+
+# FM from Skyworks eval / dabpi si46xx_firmware folder:
+python3 tools/fetch_si4684_firmware.py --si46xx-dir /path/to/si46xx_firmware
+
+# FM extracted from uGreen DABBoard radio_cli (Files_v16.zip from ugreen.eu/downloads):
+python3 tools/fetch_si4684_firmware.py --from-ugreen-radio-cli ~/Downloads/Files_v16.zip
+
+# Patch + DAB + FM entirely from uGreen radio_cli (overrides PE5PVB DAB):
+python3 tools/fetch_si4684_firmware.py --from-ugreen-radio-cli ~/Downloads/Files_v16.zip --ugreen-all
+
+# FM extracted from a full SPI flash dump (TechniSat layout, dirb.me tech wiki):
+python3 tools/fetch_si4684_firmware.py --flash-dump technisat_spi.bin
+```
+
+FM images are **not** redistributed with PE5PVB (DAB-only project). Obtain
+`fm_radio_5_1_0.bin` from the Si4684 evaluation package (AN649 table 1),
+community `si46xx_firmware/` folders used by [teknoid/dabpi](https://github.com/teknoid/dabpi),
+or extract from a uGreen [DABBoard](https://ugreen.eu/downloads/) `radio_cli`
+binary (proprietary — keep local, do not commit to public git).
+
+Low-level conversion helper:
+
+```bash
+python3 tools/extract_si4684_blob.py --copy /path/to/fm_radio_5_1_0.bin \\
+    --out Firmware/Si4684-Firmware/fm_firmware.bin
+```

Software/README.md

@@ -2,7 +2,7 @@
 
 Open-source Hi-Fi DAB+/FM receiver firmware for the ESP32-S3.
 
-**Status:** Slice 2 — secure store and Wi-Fi STA provisioning.
+**Status:** Slice 3 — Si4684 + ADAU1701 boot at power-up (network from Slice 2).
 
 ## Quick start
 
@@ -37,11 +37,11 @@ Manual PDF (design + HTTP API + class reference):
 cd docs/manual && latexmk -lualatex manual.tex
 ```
 
-## HTTP API (fw 0.2.0)
+## HTTP API (fw 0.3.0)
 
 | Method | Path | Purpose |
 |--------|------|---------|
-| GET | `/api/health` | `{"status":"ok","fw":"0.2.0"}` |
+| GET | `/api/health` | `{"status":"ok","fw":"0.3.0"}` |
 | POST | `/api/wifi` | Provision STA credentials; reboot on success |
 
 Full schemas, error tokens, and boot flow: [`docs/manual/ch-api.tex`](docs/manual/ch-api.tex).
@@ -49,6 +49,12 @@ C++ signatures: generate with `doxygen Doxyfile` → `docs/api/html/index.html`.
 
 ## Layout
 
+| Path | Role |
+|------|------|
+| `Firmware/` | Si4684 `.bin` blobs (DAB+FM) + ADAU1701 SigmaStudio export |
+| `components/drivers/si4684/` | AN649 SPI boot driver |
+| `components/drivers/adau1701/` | I2C SigmaStudio RAM download |
+
 See [`AGENTS.md`](AGENTS.md) §12 and [`instructions.md`](instructions.md) for
 the authoritative repo layout, coding rules, and development roadmap.
 

Software/components/core/CMakeLists.txt

@@ -7,6 +7,9 @@ idf_component_register(
         "src/WifiSsid.cpp"
         "src/WifiCredentials.cpp"
         "src/WifiProvisionJson.cpp"
+        "src/EmbeddedBlobReader.cpp"
+        "src/TunerJson.cpp"
+        "src/FrequencyKHz.cpp"
     INCLUDE_DIRS "include"
 )
 

Software/components/core/include/core/EmbeddedBlobReader.hpp

@@ -0,0 +1,57 @@
+/**
+ * @file    EmbeddedBlobReader.hpp
+ * @brief   IFirmwareBlobReader over a contiguous embedded flash region.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#include "core/IFirmwareBlobReader.hpp"
+
+#include <cstddef>
+#include <span>
+
+namespace core {
+
+/**
+ * @brief    EmbeddedBlobReader — non-owning view of an embedded binary.
+ *
+ * @dname    EmbeddedBlobReader
+ * @return   n/a (type)
+ * @pubstate Borrows [data_, data_ + size_) for the reader lifetime.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+class EmbeddedBlobReader final : public IFirmwareBlobReader {
+public:
+    /**
+     * @brief    EmbeddedBlobReader — construct over a flash-backed range.
+     *
+     * @dname    EmbeddedBlobReader
+     * @param    data  Start of embedded blob (e.g. linker symbol).
+     * @param    size  Length in bytes.
+     * @pubstate stores data_ and size_.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    EmbeddedBlobReader(const std::byte* data, std::size_t size);
+
+    [[nodiscard]] std::size_t size() const override;
+
+    [[nodiscard]] std::size_t read(std::size_t offset,
+                                   std::span<std::byte> dest) const override;
+
+private:
+    const std::byte* data_;
+    std::size_t size_;
+};
+
+} // namespace core

Software/components/core/include/core/FrequencyKHz.hpp

@@ -0,0 +1,73 @@
+/**
+ * @file    FrequencyKHz.hpp
+ * @brief   Strong type for FM centre frequency in kilohertz.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#include "core/ParseError.hpp"
+
+#include <cstdint>
+#include <expected>
+
+namespace core {
+
+/**
+ * @brief    FrequencyKHz — validated FM centre frequency (European band).
+ *
+ * @dname    FrequencyKHz
+ * @return   n/a (type)
+ * @pubstate Owns khz_ within 64\,000–108\,000 kHz. Immutable after construction.
+ *
+ * Parsed once at the HTTP boundary; trusted downstream by ITuner and drivers.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+class FrequencyKHz {
+public:
+    /** Minimum valid FM frequency for DigiRadio (64.0 MHz). */
+    static constexpr std::uint32_t kMinKhz = 64000U;
+    /** Maximum valid FM frequency for DigiRadio (108.0 MHz). */
+    static constexpr std::uint32_t kMaxKhz = 108000U;
+
+    /**
+     * @brief    tryFromKhz — validate an FM frequency at the boundary.
+     *
+     * @dname    tryFromKhz
+     * @param    khz  Untrusted frequency in kilohertz from JSON input.
+     * @return   FrequencyKHz on success, or ParseError::MissingField.
+     * @pubstate none
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] static std::expected<FrequencyKHz, ParseError> tryFromKhz(
+        std::uint32_t khz) noexcept;
+
+    /**
+     * @brief    value — read the stored frequency in kilohertz.
+     *
+     * @dname    value
+     * @return   Validated centre frequency in kHz.
+     * @pubstate reads khz_.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::uint32_t value() const noexcept;
+
+private:
+    explicit FrequencyKHz(std::uint32_t khz) noexcept;
+
+    std::uint32_t khz_;
+};
+
+} // namespace core

Software/components/core/include/core/IFirmwareBlobReader.hpp

@@ -0,0 +1,72 @@
+/**
+ * @file    IFirmwareBlobReader.hpp
+ * @brief   Read-only streaming access to a firmware blob in flash.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#include <cstddef>
+#include <span>
+
+namespace core {
+
+/**
+ * @brief    IFirmwareBlobReader — streaming firmware image access.
+ *
+ * @dname    IFirmwareBlobReader
+ * @return   n/a (type)
+ * @pubstate Implementations wrap embedded flash or test buffers. Used by
+ *           Si4684Driver to HOST_LOAD in bounded chunks (AGENTS.md §7.1).
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+class IFirmwareBlobReader {
+public:
+    /**
+     * @brief    ~IFirmwareBlobReader — virtual destructor.
+     *
+     * @dname    ~IFirmwareBlobReader
+     * @pubstate n/a
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    virtual ~IFirmwareBlobReader() = default;
+
+    /**
+     * @brief    size — total blob length in bytes.
+     *
+     * @dname    size
+     * @return   Blob size.
+     * @pubstate reads backing storage.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] virtual std::size_t size() const = 0;
+
+    /**
+     * @brief    read — copy bytes from the blob at an offset.
+     *
+     * @dname    read
+     * @param    offset  Byte offset from the start of the blob.
+     * @param    dest    Destination buffer; truncated at end of blob.
+     * @return   Number of bytes copied into dest.
+     * @pubstate reads backing storage.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] virtual std::size_t read(std::size_t offset,
+                                           std::span<std::byte> dest) const = 0;
+};
+
+} // namespace core

Software/components/core/include/core/ITuner.hpp

@@ -0,0 +1,170 @@
+/**
+ * @file    ITuner.hpp
+ * @brief   Abstract tuner driver boundary (host-testable).
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#include "core/FrequencyKHz.hpp"
+#include "core/SeekDirection.hpp"
+#include "core/TunerBand.hpp"
+#include "core/TunerError.hpp"
+#include "core/TunerStatus.hpp"
+
+#include <cstdint>
+#include <expected>
+#include <vector>
+
+namespace core {
+
+/**
+ * @brief    ITuner — hardware abstraction for DAB/FM tuning.
+ *
+ * @dname    ITuner
+ * @return   n/a (type)
+ * @pubstate Implemented by si4684::Si4684Tuner on device; fakes in host tests.
+ *           No public data members.
+ *
+ * Services depend on this interface, not on SPI details. All methods return
+ * std::expected with TunerError on failure.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+class ITuner {
+public:
+    virtual ~ITuner() = default;
+
+    /**
+     * @brief    boot — load the requested band application image.
+     *
+     * @dname    boot
+     * @param    band  DAB or FM image to load.
+     * @return   Ok on success, or TunerError::HardwareFailed / NotBooted.
+     * @pubstate none (implementation-defined driver state).
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] virtual std::expected<void, TunerError> boot(
+        TunerBand band) = 0;
+
+    /**
+     * @brief    currentBand — read the loaded application band.
+     *
+     * @dname    currentBand
+     * @return   Active TunerBand, or TunerError::NotBooted.
+     * @pubstate reads driver boot state.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] virtual std::expected<TunerBand, TunerError> currentBand()
+        const = 0;
+
+    /**
+     * @brief    readStatus — snapshot lock, metrics, and tune target.
+     *
+     * @dname    readStatus
+     * @return   TunerStatus on success, or a TunerError.
+     * @pubstate reads driver metrics; may refresh RSQ/DIGRAD.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] virtual std::expected<TunerStatus, TunerError> readStatus() = 0;
+
+    /**
+     * @brief    tuneDab — select a Band III ensemble by index.
+     *
+     * @dname    tuneDab
+     * @param    freqIndex  Ensemble index 0–37.
+     * @return   Ok on success, or WrongBand / TuneFailed / NotBooted.
+     * @pubstate writes last tune target in the adapter.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] virtual std::expected<void, TunerError> tuneDab(
+        std::uint8_t freqIndex) = 0;
+
+    /**
+     * @brief    tuneFm — tune to an FM centre frequency.
+     *
+     * @dname    tuneFm
+     * @param    frequency  Validated FM centre frequency.
+     * @return   Ok on success, or WrongBand / TuneFailed / NotBooted.
+     * @pubstate writes last tune target in the adapter.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] virtual std::expected<void, TunerError> tuneFm(
+        FrequencyKHz frequency) = 0;
+
+    /**
+     * @brief    seekFm — seek to the next valid FM station.
+     *
+     * @dname    seekFm
+     * @param    direction  Up or Down scan direction.
+     * @return   New centre frequency, or a TunerError.
+     * @pubstate updates last tune target on success.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] virtual std::expected<FrequencyKHz, TunerError> seekFm(
+        SeekDirection direction) = 0;
+
+    /**
+     * @brief    listDabServices — fetch programmes for the current ensemble.
+     *
+     * @dname    listDabServices
+     * @return   Service entries, ServiceListEmpty, WrongBand, or NotBooted.
+     * @pubstate reads DAB service list from the driver.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] virtual std::expected<std::vector<TunerServiceEntry>,
+                                        TunerError>
+    listDabServices() = 0;
+
+    /**
+     * @brief    playDabService — start DAB audio for a programme.
+     *
+     * @dname    playDabService
+     * @param    serviceId    Selected service identifier.
+     * @param    componentId  Audio component within the service.
+     * @return   Ok on success, or WrongBand / HardwareFailed / NotBooted.
+     * @pubstate starts digital audio output on the tuner I2S port.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] virtual std::expected<void, TunerError> playDabService(
+        std::uint32_t serviceId, std::uint32_t componentId) = 0;
+
+    /**
+     * @brief    setVolume — set tuner output attenuation.
+     *
+     * @dname    setVolume
+     * @param    level  Attenuator 0–63.
+     * @return   Ok on success, or HardwareFailed / NotBooted.
+     * @pubstate writes volume property on the driver.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] virtual std::expected<void, TunerError> setVolume(
+        std::uint8_t level) = 0;
+};
+
+} // namespace core

Software/components/core/include/core/SeekDirection.hpp

@@ -0,0 +1,31 @@
+/**
+ * @file    SeekDirection.hpp
+ * @brief   FM seek direction selector (core domain).
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+namespace core {
+
+/**
+ * @brief    SeekDirection — FM seek scan direction.
+ *
+ * @dname    SeekDirection
+ * @return   n/a (type)
+ * @pubstate n/a
+ *
+ * Replaces bare bool parameters in public tuner APIs (AGENTS.md §2.1).
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+enum class SeekDirection { Up, Down };
+
+} // namespace core

Software/components/core/include/core/TunerBand.hpp

@@ -0,0 +1,29 @@
+/**
+ * @file    TunerBand.hpp
+ * @brief   Strong band selector for tuner operations (core domain).
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+namespace core {
+
+/**
+ * @brief    TunerBand — active RF application (DAB or FM image).
+ *
+ * @dname    TunerBand
+ * @return   n/a (type)
+ * @pubstate n/a
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+enum class TunerBand { Dab, Fm };
+
+} // namespace core

Software/components/core/include/core/TunerError.hpp

@@ -0,0 +1,36 @@
+/**
+ * @file    TunerError.hpp
+ * @brief   Typed errors for tuner service and ITuner adapters.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+namespace core {
+
+/**
+ * @brief    TunerError — failure causes for tuner operations.
+ *
+ * @dname    TunerError
+ * @return   n/a (type)
+ * @pubstate Stable error set mapped from driver failures at the service boundary.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+enum class TunerError {
+    NotBooted,
+    WrongBand,
+    HardwareFailed,
+    TuneFailed,
+    ServiceListEmpty,
+    InvalidInput,
+};
+
+} // namespace core

Software/components/core/include/core/TunerJson.hpp

@@ -0,0 +1,131 @@
+/**
+ * @file    TunerJson.hpp
+ * @brief   JSON parse/serialise for tuner API (pure core).
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#include "core/FrequencyKHz.hpp"
+#include "core/ParseError.hpp"
+#include "core/TunerBand.hpp"
+#include "core/TunerStatus.hpp"
+
+#include <cstdint>
+#include <expected>
+#include <optional>
+#include <string>
+#include <string_view>
+#include <vector>
+
+namespace core {
+
+/**
+ * @brief    TunerTuneRequest — parsed POST /api/tuner/tune body.
+ *
+ * @dname    TunerTuneRequest
+ * @return   n/a (type)
+ * @pubstate Plain DTO filled by parseTunerTuneJson at the HTTP boundary.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct TunerTuneRequest {
+    TunerBand band;              ///< Target band (Dab or Fm).
+    std::uint8_t dabFreqIndex;   ///< Band III ensemble index (0–37) when band is Dab.
+    std::optional<FrequencyKHz> fmFrequency; ///< FM centre frequency when band is Fm.
+};
+
+/**
+ * @brief    TunerPlayRequest — parsed POST /api/tuner/play body.
+ *
+ * @dname    TunerPlayRequest
+ * @return   n/a (type)
+ * @pubstate Plain DTO filled by parseTunerPlayJson at the HTTP boundary.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct TunerPlayRequest {
+    std::uint32_t serviceId;    ///< DAB service identifier from the ensemble list.
+    std::uint32_t componentId;  ///< Audio component within the service.
+};
+
+/**
+ * @brief    serializeTunerStatusJson — serialise a tuner snapshot for GET status.
+ *
+ * @dname    serializeTunerStatusJson
+ * @param    status  Domain snapshot from TunerService::refreshStatus().
+ * @return   JSON object string for the HTTP response body.
+ * @pubstate none
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+[[nodiscard]] std::string serializeTunerStatusJson(const TunerStatus& status);
+
+/**
+ * @brief    serializeTunerServicesJson — serialise the DAB service list.
+ *
+ * @dname    serializeTunerServicesJson
+ * @param    services  Programme entries for the current ensemble.
+ * @return   JSON object string with a services array.
+ * @pubstate none
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+[[nodiscard]] std::string serializeTunerServicesJson(
+    const std::vector<TunerServiceEntry>& services);
+
+/**
+ * @brief    serializeTunerErrorJson — serialise a tuner API error response.
+ *
+ * @dname    serializeTunerErrorJson
+ * @param    reason  Short machine-readable cause (never a secret).
+ * @return   JSON object string with status error and reason fields.
+ * @pubstate none
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+[[nodiscard]] std::string serializeTunerErrorJson(const char* reason);
+
+/**
+ * @brief    parseTunerTuneJson — validate POST /api/tuner/tune body.
+ *
+ * @dname    parseTunerTuneJson
+ * @param    json  Untrusted request body from the HTTP handler.
+ * @return   TunerTuneRequest on success, or a ParseError.
+ * @pubstate none
+ *
+ * Rejects malformed JSON, missing fields, and out-of-range frequencies
+ * before any driver call.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+[[nodiscard]] std::expected<TunerTuneRequest, ParseError> parseTunerTuneJson(
+    std::string_view json);
+
+/**
+ * @brief    parseTunerPlayJson — validate POST /api/tuner/play body.
+ *
+ * @dname    parseTunerPlayJson
+ * @param    json  Untrusted request body from the HTTP handler.
+ * @return   TunerPlayRequest on success, or a ParseError.
+ * @pubstate none
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+[[nodiscard]] std::expected<TunerPlayRequest, ParseError> parseTunerPlayJson(
+    std::string_view json);
+
+} // namespace core

Software/components/core/include/core/TunerStatus.hpp

@@ -0,0 +1,65 @@
+/**
+ * @file    TunerStatus.hpp
+ * @brief   Tuner status DTO for API and UI (pure core).
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#include "core/FrequencyKHz.hpp"
+#include "core/TunerBand.hpp"
+
+#include <array>
+#include <cstdint>
+#include <optional>
+
+namespace core {
+
+/**
+ * @brief    TunerServiceEntry — one DAB programme in the current ensemble.
+ *
+ * @dname    TunerServiceEntry
+ * @return   n/a (type)
+ * @pubstate Plain DTO returned by ITuner::listDabServices().
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct TunerServiceEntry {
+    std::uint32_t serviceId;    ///< DAB service identifier.
+    std::uint32_t componentId;  ///< Audio component within the service.
+    std::array<char, 17> label; ///< UTF-8 programme label, NUL-terminated.
+};
+
+/**
+ * @brief    TunerStatus — snapshot for GET /api/tuner/status.
+ *
+ * @dname    TunerStatus
+ * @return   n/a (type)
+ * @pubstate Plain DTO built by ITuner::readStatus(); serialised by
+ *           serializeTunerStatusJson(). Band-specific fields are optional.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct TunerStatus {
+    bool booted;                              ///< Companion tuner boot completed.
+    TunerBand band;                           ///< Active loaded application band.
+    bool locked;                              ///< RF lock / valid signal.
+    std::uint8_t volume;                      ///< Attenuator level 0–63.
+    std::optional<std::uint8_t> dabFreqIndex; ///< Current Band III ensemble index.
+    std::optional<std::uint8_t> dabFicQuality; ///< FIC quality 0–100 when DAB.
+    std::optional<std::int8_t> dabCnrDb;    ///< CNR in dB when DAB.
+    std::optional<FrequencyKHz> fmFrequency; ///< Tuned FM centre frequency.
+    std::optional<std::int8_t> fmRssiDbuV;  ///< FM RSSI in dBµV.
+    std::optional<std::int8_t> fmSnrDb;     ///< FM SNR in dB.
+    std::optional<bool> fmStereo;           ///< FM stereo pilot detected.
+};
+
+} // namespace core

Software/components/core/src/EmbeddedBlobReader.cpp

@@ -0,0 +1,44 @@
+/**
+ * @file    EmbeddedBlobReader.cpp
+ * @brief   EmbeddedBlobReader implementation.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "core/EmbeddedBlobReader.hpp"
+
+#include <algorithm>
+#include <cstring>
+
+namespace core {
+
+EmbeddedBlobReader::EmbeddedBlobReader(const std::byte* data, std::size_t size)
+    : data_(data)
+    , size_(size)
+{
+}
+
+std::size_t EmbeddedBlobReader::size() const
+{
+    return size_;
+}
+
+std::size_t EmbeddedBlobReader::read(std::size_t offset,
+                                     std::span<std::byte> dest) const
+{
+    if (offset >= size_ || dest.empty()) {
+        return 0;
+    }
+    const std::size_t available = size_ - offset;
+    const std::size_t toCopy = std::min(available, dest.size());
+    std::memcpy(dest.data(), data_ + offset, toCopy);
+    return toCopy;
+}
+
+} // namespace core

Software/components/core/src/FrequencyKHz.cpp

@@ -0,0 +1,37 @@
+/**
+ * @file    FrequencyKHz.cpp
+ * @brief   FrequencyKHz implementation.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "core/FrequencyKHz.hpp"
+
+namespace core {
+
+FrequencyKHz::FrequencyKHz(std::uint32_t khz) noexcept
+    : khz_(khz)
+{
+}
+
+std::expected<FrequencyKHz, ParseError> FrequencyKHz::tryFromKhz(
+    std::uint32_t khz) noexcept
+{
+    if (khz < kMinKhz || khz > kMaxKhz) {
+        return std::unexpected(ParseError::MissingField);
+    }
+    return FrequencyKHz(khz);
+}
+
+std::uint32_t FrequencyKHz::value() const noexcept
+{
+    return khz_;
+}
+
+} // namespace core

Software/components/core/src/TunerJson.cpp

@@ -0,0 +1,198 @@
+/**
+ * @file    TunerJson.cpp
+ * @brief   TunerJson implementation.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "core/TunerJson.hpp"
+
+#include <cstdlib>
+#include <sstream>
+
+namespace core {
+
+namespace {
+
+[[nodiscard]] std::string_view extractJsonString(std::string_view json,
+                                                 std::string_view key)
+{
+    const std::string needle =
+        std::string("\"") + std::string(key) + "\":\"";
+    const std::size_t start = json.find(needle);
+    if (start == std::string_view::npos) {
+        return {};
+    }
+    const std::size_t valueStart = start + needle.size();
+    const std::size_t valueEnd = json.find('"', valueStart);
+    if (valueEnd == std::string_view::npos) {
+        return {};
+    }
+    return json.substr(valueStart, valueEnd - valueStart);
+}
+
+[[nodiscard]] bool extractJsonUint(std::string_view json,
+                                   std::string_view key,
+                                   unsigned long& out)
+{
+    const std::string needle =
+        std::string("\"") + std::string(key) + "\":";
+    const std::size_t start = json.find(needle);
+    if (start == std::string_view::npos) {
+        return false;
+    }
+    const std::size_t valueStart = start + needle.size();
+    char* end = nullptr;
+    out = std::strtoul(json.data() + valueStart, &end, 10);
+    return end != json.data() + valueStart;
+}
+
+[[nodiscard]] const char* bandToken(TunerBand band) noexcept
+{
+    return band == TunerBand::Fm ? "fm" : "dab";
+}
+
+} // namespace
+
+std::string serializeTunerStatusJson(const TunerStatus& status)
+{
+    std::ostringstream out;
+    out << "{\"booted\":" << (status.booted ? "true" : "false")
+        << ",\"band\":\"" << bandToken(status.band) << "\""
+        << ",\"locked\":" << (status.locked ? "true" : "false")
+        << ",\"volume\":" << static_cast<unsigned>(status.volume);
+
+    if (status.band == TunerBand::Dab) {
+        out << ",\"dab\":{";
+        if (status.dabFreqIndex) {
+            out << "\"freq_index\":" << static_cast<unsigned>(*status.dabFreqIndex);
+        }
+        if (status.dabFicQuality) {
+            if (status.dabFreqIndex) {
+                out << ',';
+            }
+            out << "\"fic_quality\":" << static_cast<unsigned>(*status.dabFicQuality);
+        }
+        if (status.dabCnrDb) {
+            out << ",\"cnr_db\":" << static_cast<int>(*status.dabCnrDb);
+        }
+        out << "},\"fm\":null";
+    } else {
+        out << ",\"fm\":{";
+        if (status.fmFrequency) {
+            out << "\"frequency_khz\":" << status.fmFrequency->value();
+        }
+        if (status.fmRssiDbuV) {
+            if (status.fmFrequency) {
+                out << ',';
+            }
+            out << "\"rssi_dbuv\":" << static_cast<int>(*status.fmRssiDbuV);
+        }
+        if (status.fmSnrDb) {
+            out << ",\"snr_db\":" << static_cast<int>(*status.fmSnrDb);
+        }
+        if (status.fmStereo) {
+            out << ",\"stereo\":" << (*status.fmStereo ? "true" : "false");
+        }
+        out << "},\"dab\":null";
+    }
+    out << '}';
+    return out.str();
+}
+
+std::string serializeTunerServicesJson(
+    const std::vector<TunerServiceEntry>& services)
+{
+    std::ostringstream out;
+    out << "{\"services\":[";
+    for (std::size_t i = 0; i < services.size(); ++i) {
+        if (i > 0U) {
+            out << ',';
+        }
+        const auto& s = services[i];
+        out << "{\"service_id\":" << s.serviceId
+            << ",\"component_id\":" << s.componentId << ",\"label\":\"";
+        for (char c : s.label) {
+            if (c == '\0') {
+                break;
+            }
+            if (c == '"' || c == '\\') {
+                out << '\\';
+            }
+            out << c;
+        }
+        out << "\"}";
+    }
+    out << "]}";
+    return out.str();
+}
+
+std::string serializeTunerErrorJson(const char* reason)
+{
+    return std::string("{\"status\":\"error\",\"reason\":\"") + reason + "\"}";
+}
+
+std::expected<TunerTuneRequest, ParseError> parseTunerTuneJson(
+    std::string_view json)
+{
+    if (json.find('{') == std::string_view::npos) {
+        return std::unexpected(ParseError::InvalidJson);
+    }
+
+    const std::string_view band = extractJsonString(json, "band");
+    if (band.empty()) {
+        return std::unexpected(ParseError::MissingField);
+    }
+
+    TunerTuneRequest req = {};
+    if (band == "dab") {
+        req.band = TunerBand::Dab;
+        unsigned long idx = 0U;
+        if (!extractJsonUint(json, "freq_index", idx) || idx > 37U) {
+            return std::unexpected(ParseError::MissingField);
+        }
+        req.dabFreqIndex = static_cast<std::uint8_t>(idx);
+    } else if (band == "fm") {
+        req.band = TunerBand::Fm;
+        unsigned long khz = 0U;
+        if (!extractJsonUint(json, "frequency_khz", khz)) {
+            return std::unexpected(ParseError::MissingField);
+        }
+        auto freq = FrequencyKHz::tryFromKhz(static_cast<std::uint32_t>(khz));
+        if (!freq) {
+            return std::unexpected(freq.error());
+        }
+        req.fmFrequency = *freq;
+    } else {
+        return std::unexpected(ParseError::InvalidJson);
+    }
+    return req;
+}
+
+std::expected<TunerPlayRequest, ParseError> parseTunerPlayJson(
+    std::string_view json)
+{
+    if (json.find('{') == std::string_view::npos) {
+        return std::unexpected(ParseError::InvalidJson);
+    }
+
+    unsigned long sid = 0U;
+    unsigned long cid = 0U;
+    if (!extractJsonUint(json, "service_id", sid)
+        || !extractJsonUint(json, "component_id", cid)) {
+        return std::unexpected(ParseError::MissingField);
+    }
+
+    TunerPlayRequest req = {};
+    req.serviceId = static_cast<std::uint32_t>(sid);
+    req.componentId = static_cast<std::uint32_t>(cid);
+    return req;
+}
+
+} // namespace core

Software/components/core/test/CMakeLists.txt

@@ -19,6 +19,9 @@ add_library(digiradio_core STATIC
     "${CORE_SRC_DIR}/WifiSsid.cpp"
     "${CORE_SRC_DIR}/WifiCredentials.cpp"
     "${CORE_SRC_DIR}/WifiProvisionJson.cpp"
+    "${CORE_SRC_DIR}/EmbeddedBlobReader.cpp"
+    "${CORE_SRC_DIR}/TunerJson.cpp"
+    "${CORE_SRC_DIR}/FrequencyKHz.cpp"
 )
 target_include_directories(digiradio_core PUBLIC
     "${CMAKE_CURRENT_SOURCE_DIR}/../include"
@@ -31,3 +34,15 @@ add_test(NAME health_status_test COMMAND health_status_test)
 add_executable(wifi_provision_test wifi_provision_test.cpp)
 target_link_libraries(wifi_provision_test PRIVATE digiradio_core)
 add_test(NAME wifi_provision_test COMMAND wifi_provision_test)
+
+add_executable(embedded_blob_reader_test embedded_blob_reader_test.cpp)
+target_link_libraries(embedded_blob_reader_test PRIVATE digiradio_core)
+add_test(NAME embedded_blob_reader_test COMMAND embedded_blob_reader_test)
+
+add_executable(tuner_json_test tuner_json_test.cpp)
+target_link_libraries(tuner_json_test PRIVATE digiradio_core)
+add_test(NAME tuner_json_test COMMAND tuner_json_test)
+
+add_executable(frequency_khz_test frequency_khz_test.cpp)
+target_link_libraries(frequency_khz_test PRIVATE digiradio_core)
+add_test(NAME frequency_khz_test COMMAND frequency_khz_test)

Software/components/core/test/embedded_blob_reader_test.cpp

@@ -0,0 +1,79 @@
+/**
+ * @file    embedded_blob_reader_test.cpp
+ * @brief   Host tests for EmbeddedBlobReader streaming reads.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "core/EmbeddedBlobReader.hpp"
+
+#include <array>
+#include <cstdlib>
+#include <iostream>
+
+namespace {
+
+bool expectEqual(std::size_t actual, std::size_t expected, const char* label)
+{
+    if (actual == expected) {
+        return true;
+    }
+    std::cerr << label << ": expected " << expected << ", got " << actual
+              << '\n';
+    return false;
+}
+
+} // namespace
+
+/**
+ * @brief    main — run EmbeddedBlobReader host tests.
+ *
+ * @dname    main
+ * @return   0 on success, 1 on failure.
+ * @pubstate none
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+int main()
+{
+    const std::array<std::byte, 8> source = {
+        std::byte{0x01}, std::byte{0x02}, std::byte{0x03}, std::byte{0x04},
+        std::byte{0x05}, std::byte{0x06}, std::byte{0x07}, std::byte{0x08},
+    };
+    core::EmbeddedBlobReader reader(source.data(), source.size());
+
+    if (!expectEqual(reader.size(), source.size(), "size")) {
+        return EXIT_FAILURE;
+    }
+
+    std::array<std::byte, 3> chunk = {};
+    if (!expectEqual(reader.read(0U, chunk), 3U, "first read length")) {
+        return EXIT_FAILURE;
+    }
+    if (chunk[0] != std::byte{0x01} || chunk[2] != std::byte{0x03}) {
+        std::cerr << "first read content mismatch\n";
+        return EXIT_FAILURE;
+    }
+
+    if (!expectEqual(reader.read(6U, chunk), 2U, "tail read length")) {
+        return EXIT_FAILURE;
+    }
+    if (chunk[0] != std::byte{0x07} || chunk[1] != std::byte{0x08}) {
+        std::cerr << "tail read content mismatch\n";
+        return EXIT_FAILURE;
+    }
+
+    if (!expectEqual(reader.read(source.size(), chunk), 0U, "past end")) {
+        return EXIT_FAILURE;
+    }
+
+    std::cout << "embedded_blob_reader_test: ok\n";
+    return EXIT_SUCCESS;
+}

Software/components/core/test/frequency_khz_test.cpp

@@ -0,0 +1,53 @@
+/**
+ * @file    frequency_khz_test.cpp
+ * @brief   Host tests for FrequencyKHz validation.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "core/FrequencyKHz.hpp"
+#include "core/ParseError.hpp"
+
+#include <cstdlib>
+#include <iostream>
+
+namespace {
+
+[[nodiscard]] int runFrequencyAcceptTest()
+{
+    const auto parsed = core::FrequencyKHz::tryFromKhz(101500U);
+    if (!parsed || parsed->value() != 101500U) {
+        std::cerr << "expected 101500 kHz accepted\n";
+        return EXIT_FAILURE;
+    }
+    return EXIT_SUCCESS;
+}
+
+[[nodiscard]] int runFrequencyRejectTest()
+{
+    const auto parsed = core::FrequencyKHz::tryFromKhz(50000U);
+    if (parsed || parsed.error() != core::ParseError::MissingField) {
+        std::cerr << "expected out-of-band frequency rejection\n";
+        return EXIT_FAILURE;
+    }
+    return EXIT_SUCCESS;
+}
+
+} // namespace
+
+int main()
+{
+    if (runFrequencyAcceptTest() != EXIT_SUCCESS) {
+        return EXIT_FAILURE;
+    }
+    if (runFrequencyRejectTest() != EXIT_SUCCESS) {
+        return EXIT_FAILURE;
+    }
+    return EXIT_SUCCESS;
+}

Software/components/core/test/tuner_json_test.cpp

@@ -0,0 +1,156 @@
+/**
+ * @file    tuner_json_test.cpp
+ * @brief   Host tests for tuner JSON parse/serialise.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "core/FrequencyKHz.hpp"
+#include "core/ParseError.hpp"
+#include "core/TunerBand.hpp"
+#include "core/TunerJson.hpp"
+#include "core/TunerStatus.hpp"
+
+#include <cstdlib>
+#include <iostream>
+#include <string>
+
+namespace {
+
+[[nodiscard]] bool expectEqual(const std::string& actual,
+                               const std::string& expected)
+{
+    if (actual == expected) {
+        return true;
+    }
+    std::cerr << "expected: " << expected << "\nactual:   " << actual << '\n';
+    return false;
+}
+
+[[nodiscard]] int runTunerTuneParseDabTest()
+{
+    const auto parsed =
+        core::parseTunerTuneJson(R"({"band":"dab","freq_index":12})");
+    if (!parsed || parsed->band != core::TunerBand::Dab
+        || parsed->dabFreqIndex != 12U) {
+        std::cerr << "DAB tune parse failed\n";
+        return EXIT_FAILURE;
+    }
+    return EXIT_SUCCESS;
+}
+
+[[nodiscard]] int runTunerTuneParseFmTest()
+{
+    const auto parsed =
+        core::parseTunerTuneJson(R"({"band":"fm","frequency_khz":101500})");
+    if (!parsed || parsed->band != core::TunerBand::Fm
+        || !parsed->fmFrequency
+        || parsed->fmFrequency->value() != 101500U) {
+        std::cerr << "FM tune parse failed\n";
+        return EXIT_FAILURE;
+    }
+    return EXIT_SUCCESS;
+}
+
+[[nodiscard]] int runTunerTuneRejectTest()
+{
+    const auto parsed =
+        core::parseTunerTuneJson(R"({"band":"fm","frequency_khz":50000})");
+    if (parsed) {
+        std::cerr << "expected FM frequency rejection\n";
+        return EXIT_FAILURE;
+    }
+    return EXIT_SUCCESS;
+}
+
+[[nodiscard]] int runTunerPlayParseTest()
+{
+    const auto parsed =
+        core::parseTunerPlayJson(R"({"service_id":42,"component_id":7})");
+    if (!parsed || parsed->serviceId != 42U || parsed->componentId != 7U) {
+        std::cerr << "play parse failed\n";
+        return EXIT_FAILURE;
+    }
+    return EXIT_SUCCESS;
+}
+
+[[nodiscard]] int runTunerStatusSerialiseTest()
+{
+    core::TunerStatus status = {};
+    status.booted = true;
+    status.band = core::TunerBand::Fm;
+    status.locked = true;
+    status.volume = 40;
+    status.fmFrequency = *core::FrequencyKHz::tryFromKhz(101500U);
+    status.fmRssiDbuV = -20;
+    status.fmSnrDb = 25;
+    status.fmStereo = true;
+
+    const std::string json = core::serializeTunerStatusJson(status);
+    if (json.find("\"booted\":true") == std::string::npos
+        || json.find("\"band\":\"fm\"") == std::string::npos
+        || json.find("\"frequency_khz\":101500") == std::string::npos) {
+        std::cerr << "status serialise missing fields: " << json << '\n';
+        return EXIT_FAILURE;
+    }
+    return EXIT_SUCCESS;
+}
+
+[[nodiscard]] int runTunerServicesSerialiseTest()
+{
+    core::TunerServiceEntry entry = {};
+    entry.serviceId = 1U;
+    entry.componentId = 2U;
+    entry.label = {'R', 'A', 'I', '\0'};
+
+    const std::string json =
+        core::serializeTunerServicesJson({entry});
+    if (!expectEqual(json,
+                     R"({"services":[{"service_id":1,"component_id":2,"label":"RAI"}]})")) {
+        return EXIT_FAILURE;
+    }
+    return EXIT_SUCCESS;
+}
+
+[[nodiscard]] int runTunerErrorSerialiseTest()
+{
+    if (!expectEqual(core::serializeTunerErrorJson("not_booted"),
+                     R"({"status":"error","reason":"not_booted"})")) {
+        return EXIT_FAILURE;
+    }
+    return EXIT_SUCCESS;
+}
+
+} // namespace
+
+int main()
+{
+    if (runTunerTuneParseDabTest() != EXIT_SUCCESS) {
+        return EXIT_FAILURE;
+    }
+    if (runTunerTuneParseFmTest() != EXIT_SUCCESS) {
+        return EXIT_FAILURE;
+    }
+    if (runTunerTuneRejectTest() != EXIT_SUCCESS) {
+        return EXIT_FAILURE;
+    }
+    if (runTunerPlayParseTest() != EXIT_SUCCESS) {
+        return EXIT_FAILURE;
+    }
+    if (runTunerStatusSerialiseTest() != EXIT_SUCCESS) {
+        return EXIT_FAILURE;
+    }
+    if (runTunerServicesSerialiseTest() != EXIT_SUCCESS) {
+        return EXIT_FAILURE;
+    }
+    if (runTunerErrorSerialiseTest() != EXIT_SUCCESS) {
+        return EXIT_FAILURE;
+    }
+    return EXIT_SUCCESS;
+}

Software/components/drivers/adau1701/CMakeLists.txt

@@ -1,6 +1,14 @@
+set(ADAU_FW_DIR "${CMAKE_CURRENT_LIST_DIR}/../../../Firmware/ADAU1701-Firmware")
+
 idf_component_register(
-    SRCS "src/component_stub.cpp"
+    SRCS
-    INCLUDE_DIRS "include"
+        "src/Adau1701Driver.cpp"
+        "src/SigmaStudioFW.c"
+        "src/adau1701_program.c"
+    INCLUDE_DIRS
+        "include"
+        "${ADAU_FW_DIR}"
+    REQUIRES driver esp_driver_gpio esp_driver_i2c
 )
 
 target_compile_features(${COMPONENT_LIB} PUBLIC cxx_std_23)

Software/components/drivers/adau1701/include/adau1701/Adau1701Driver.hpp

@@ -0,0 +1,112 @@
+/**
+ * @file    Adau1701Driver.hpp
+ * @brief   ADAU1701 SigmaDSP driver — RAM boot on every power-up.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#include "adau1701/Adau1701Error.hpp"
+
+#include <expected>
+
+namespace adau1701 {
+
+/**
+ * @brief    Adau1701Pins — board GPIO/I2C identifiers for the DSP.
+ *
+ * @dname    Adau1701Pins
+ * @return   n/a (type)
+ * @pubstate Immutable wiring snapshot from board_pins.hpp.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct Adau1701Pins {
+    int i2cSda;    ///< I2C SDA GPIO.
+    int i2cScl;    ///< I2C SCL GPIO.
+    int resetGpio; ///< DSP RESET# GPIO (active low).
+    int i2cAddr7;  ///< 7-bit I2C address of the ADAU1701.
+};
+
+/**
+ * @brief    Adau1701Driver — owns I2C + reset and loads SigmaStudio RAM.
+ *
+ * @dname    Adau1701Driver
+ * @param    pins  Board wiring for I2C and RESET#.
+ * @return   n/a (type)
+ * @pubstate Owns I2C bus/device handles (RAII). booted_ true after a
+ *           successful default_download replay.
+ *
+ * Writes the SigmaStudio export from Firmware/ADAU1701-Firmware on every
+ * boot (no EEPROM self-boot on DigiRadio).
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+class Adau1701Driver {
+public:
+    /**
+     * @brief    Adau1701Driver — construct with board pin map.
+     *
+     * @dname    Adau1701Driver
+     * @param    pins  SDA/SCL/reset/address configuration.
+     * @pubstate stores pins_; not booted until boot().
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    explicit Adau1701Driver(Adau1701Pins pins);
+
+    /**
+     * @brief    ~Adau1701Driver — release I2C resources.
+     *
+     * @dname    ~Adau1701Driver
+     * @pubstate deletes bus/device handles when created.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    ~Adau1701Driver();
+
+    Adau1701Driver(const Adau1701Driver&) = delete;
+    Adau1701Driver& operator=(const Adau1701Driver&) = delete;
+
+    /**
+     * @brief    boot — reset the DSP and replay the SigmaStudio download.
+     *
+     * @dname    boot
+     * @return   Ok on success, or Adau1701Error.
+     * @pubstate writes booted_ on success; uses embedded program data.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, Adau1701Error> boot();
+
+    /**
+     * @brief    isBooted — query whether RAM download succeeded.
+     *
+     * @dname    isBooted
+     * @return   true after a successful boot().
+     * @pubstate reads booted_.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] bool isBooted() const noexcept;
+
+private:
+    Adau1701Pins pins_;
+    bool booted_;
+    void* i2cBus_;
+    void* i2cDev_;
+};
+
+} // namespace adau1701

Software/components/drivers/adau1701/include/adau1701/Adau1701Error.hpp

@@ -0,0 +1,33 @@
+/**
+ * @file    Adau1701Error.hpp
+ * @brief   Typed errors for ADAU1701 driver operations.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+namespace adau1701 {
+
+/**
+ * @brief    Adau1701Error — failure causes for ADAU1701 bring-up.
+ *
+ * @dname    Adau1701Error
+ * @return   n/a (type)
+ * @pubstate n/a
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+enum class Adau1701Error {
+    I2cInitFailed,
+    ResetFailed,
+    DownloadFailed,
+};
+
+} // namespace adau1701

Software/components/drivers/adau1701/src/Adau1701Driver.cpp

@@ -0,0 +1,118 @@
+/**
+ * @file    Adau1701Driver.cpp
+ * @brief   Adau1701Driver implementation.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "adau1701/Adau1701Driver.hpp"
+
+#include "SigmaStudioFW.h"
+
+#include "driver/gpio.h"
+#include "driver/i2c_master.h"
+#include "esp_log.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+
+extern "C" {
+
+/** @brief SigmaStudio default program download (generated C, not part of the C++ API). */
+void adau1701_run_default_download(void);
+
+} // extern "C"
+
+namespace adau1701 {
+
+namespace {
+constexpr char kTag[] = "Adau1701";
+constexpr int kI2cPort = 0;
+} // namespace
+
+Adau1701Driver::Adau1701Driver(Adau1701Pins pins)
+    : pins_(pins)
+    , booted_(false)
+    , i2cBus_(nullptr)
+    , i2cDev_(nullptr)
+{
+}
+
+Adau1701Driver::~Adau1701Driver()
+{
+    auto* dev = static_cast<i2c_master_dev_handle_t>(i2cDev_);
+    auto* bus = static_cast<i2c_master_bus_handle_t>(i2cBus_);
+    if (dev != nullptr) {
+        i2c_master_bus_rm_device(dev);
+    }
+    if (bus != nullptr) {
+        i2c_del_master_bus(bus);
+    }
+}
+
+std::expected<void, Adau1701Error> Adau1701Driver::boot()
+{
+    if (booted_) {
+        return {};
+    }
+
+    gpio_config_t resetCfg = {};
+    resetCfg.pin_bit_mask = 1ULL << pins_.resetGpio;
+    resetCfg.mode = GPIO_MODE_OUTPUT;
+    if (gpio_config(&resetCfg) != ESP_OK) {
+        return std::unexpected(Adau1701Error::ResetFailed);
+    }
+
+    gpio_set_level(static_cast<gpio_num_t>(pins_.resetGpio), 0);
+    vTaskDelay(pdMS_TO_TICKS(10));
+    gpio_set_level(static_cast<gpio_num_t>(pins_.resetGpio), 1);
+    vTaskDelay(pdMS_TO_TICKS(10));
+
+    i2c_master_bus_config_t busCfg = {};
+    busCfg.i2c_port = static_cast<i2c_port_num_t>(kI2cPort);
+    busCfg.sda_io_num = static_cast<gpio_num_t>(pins_.i2cSda);
+    busCfg.scl_io_num = static_cast<gpio_num_t>(pins_.i2cScl);
+    busCfg.clk_source = I2C_CLK_SRC_DEFAULT;
+    busCfg.glitch_ignore_cnt = 7;
+    busCfg.flags.enable_internal_pullup = true;
+
+    i2c_master_bus_handle_t bus = nullptr;
+    if (i2c_new_master_bus(&busCfg, &bus) != ESP_OK) {
+        ESP_LOGE(kTag, "i2c_new_master_bus failed");
+        return std::unexpected(Adau1701Error::I2cInitFailed);
+    }
+    i2cBus_ = bus;
+
+    i2c_device_config_t devCfg = {};
+    devCfg.dev_addr_length = I2C_ADDR_BIT_LEN_7;
+    devCfg.device_address = static_cast<uint16_t>(pins_.i2cAddr7);
+    devCfg.scl_speed_hz = 100000;
+
+    i2c_master_dev_handle_t dev = nullptr;
+    if (i2c_master_bus_add_device(bus, &devCfg, &dev) != ESP_OK) {
+        ESP_LOGE(kTag, "i2c_master_bus_add_device failed");
+        return std::unexpected(Adau1701Error::I2cInitFailed);
+    }
+    i2cDev_ = dev;
+
+    sigma_studio_bind_i2c(kI2cPort, static_cast<unsigned char>(pins_.i2cAddr7));
+    sigma_studio_set_device(dev);
+
+    adau1701_run_default_download();
+
+    booted_ = true;
+    ESP_LOGI(kTag, "SigmaStudio program loaded");
+    return {};
+}
+
+bool Adau1701Driver::isBooted() const noexcept
+{
+    return booted_;
+}
+
+} // namespace adau1701

Software/components/drivers/adau1701/src/SigmaStudioFW.c

@@ -0,0 +1,60 @@
+/**
+ * @file    SigmaStudioFW.c
+ * @brief   SigmaStudio SIGMA_WRITE_REGISTER_BLOCK for ESP-IDF I2C.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "SigmaStudioFW.h"
+
+#include "driver/i2c_master.h"
+
+#include <string.h>
+
+static i2c_master_dev_handle_t s_dev = NULL;
+
+void sigma_studio_bind_i2c(int port, unsigned char addr7)
+{
+    (void)port;
+    (void)addr7;
+}
+
+void sigma_studio_set_device(void* i2cDevHandle)
+{
+    s_dev = (i2c_master_dev_handle_t)i2cDevHandle;
+}
+
+void SIGMA_WRITE_REGISTER_BLOCK(unsigned char devAddress,
+                                unsigned int address,
+                                unsigned char length,
+                                ADI_REG_TYPE* pData)
+{
+    (void)devAddress;
+    if (s_dev == NULL || pData == NULL || length == 0U) {
+        return;
+    }
+
+    enum { kChunk = 64U };
+    unsigned int addr = address;
+    unsigned char remaining = length;
+    ADI_REG_TYPE* cursor = pData;
+
+    while (remaining > 0U) {
+        const unsigned char chunk =
+            remaining > kChunk ? kChunk : remaining;
+        unsigned char buf[2U + 64U];
+        buf[0] = (unsigned char)((addr >> 8) & 0xFFU);
+        buf[1] = (unsigned char)(addr & 0xFFU);
+        memcpy(buf + 2U, cursor, chunk);
+        i2c_master_transmit(s_dev, buf, (size_t)(2U + chunk), 1000);
+        addr += chunk;
+        cursor += chunk;
+        remaining = (unsigned char)(remaining - chunk);
+    }
+}

Software/components/drivers/adau1701/src/adau1701_program.c

@@ -0,0 +1,20 @@
+/**
+ * @file    adau1701_program.c
+ * @brief   SigmaStudio default download for DigiRadio ADAU1701.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "SigmaStudioFW.h"
+#include "DigiRadio_IC_1.h"
+
+void adau1701_run_default_download(void)
+{
+    default_download_IC_1();
+}

Software/components/drivers/adau1701/src/component_stub.cpp

@@ -1,33 +0,0 @@
-/**
- * @file    component_stub.cpp
- * @brief   ADAU1701 driver component placeholder (Slice 5).
- *
- * DigiRadio firmware — https://github.com/manvalan/DigiRadio
- *
- * Copyright 2026 Michele Bigi
- * SPDX-License-Identifier: Apache-2.0
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * @author  Michele Bigi
- * @date    2026-07-06
- */
-
-namespace adau1701::detail {
-
-/**
- * @brief    adau1701ComponentLinked — ensures the driver component links.
- *
- * @dname    adau1701ComponentLinked
- * @return   n/a (type)
- * @pubstate n/a
- *
- * @author   Michele Bigi
- * @date     2026-07-06
- */
-void adau1701ComponentLinked() noexcept {}
-
-} // namespace adau1701::detail

Software/components/drivers/si4684/CMakeLists.txt

@@ -1,6 +1,23 @@
+set(SI4684_FW_DIR "${CMAKE_CURRENT_LIST_DIR}/../../../Firmware/Si4684-Firmware")
+
+if(NOT EXISTS "${SI4684_FW_DIR}/fm_firmware.bin")
+    message(FATAL_ERROR
+        "Missing ${SI4684_FW_DIR}/fm_firmware.bin — run:\n"
+        "  python3 tools/fetch_si4684_firmware.py --from-ugreen-radio-cli <Files_v16.zip>\n"
+        "  python3 tools/fetch_si4684_firmware.py --si46xx-dir <si46xx_firmware>")
+endif()
+
 idf_component_register(
-    SRCS "src/component_stub.cpp"
+    SRCS
+        "src/Si4684Driver.cpp"
+        "src/Si4684EmbeddedImages.cpp"
+        "src/Si4684Tuner.cpp"
     INCLUDE_DIRS "include"
+    REQUIRES core driver esp_driver_gpio esp_driver_spi
+    EMBED_FILES
+        "${SI4684_FW_DIR}/rom_patch_016.bin"
+        "${SI4684_FW_DIR}/dab_firmware.bin"
+        "${SI4684_FW_DIR}/fm_firmware.bin"
 )
 
 target_compile_features(${COMPONENT_LIB} PUBLIC cxx_std_23)

Software/components/drivers/si4684/include/si4684/Si4684Band.hpp

@@ -0,0 +1,32 @@
+/**
+ * @file    Si4684Band.hpp
+ * @brief   Tuner band selection for Si4684 firmware images.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+namespace si4684 {
+
+/**
+ * @brief    Si4684Band — application image loaded after ROM patch.
+ *
+ * @dname    Si4684Band
+ * @return   n/a (type)
+ * @pubstate n/a
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+enum class Si4684Band {
+    Dab,
+    Fm,
+};
+
+} // namespace si4684

Software/components/drivers/si4684/include/si4684/Si4684Driver.hpp

@@ -0,0 +1,370 @@
+/**
+ * @file    Si4684Driver.hpp
+ * @brief   Si4684 DAB+/FM tuner — boot, tuning, status, and service control.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#include "core/FrequencyKHz.hpp"
+#include "core/IFirmwareBlobReader.hpp"
+#include "core/SeekDirection.hpp"
+#include "si4684/Si4684Band.hpp"
+#include "si4684/Si4684Error.hpp"
+#include "si4684/Si4684Types.hpp"
+
+#include <cstdint>
+#include <expected>
+#include <span>
+#include <vector>
+
+namespace si4684 {
+
+/**
+ * @brief    Si4684Pins — board GPIO/SPI identifiers for the tuner.
+ *
+ * @dname    Si4684Pins
+ * @return   n/a (type)
+ * @pubstate Immutable wiring snapshot from board_pins.hpp.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct Si4684Pins {
+    int spiHost;  ///< ESP32 SPI host peripheral index.
+    int csGpio;   ///< Chip-select GPIO.
+    int misoGpio; ///< MISO GPIO.
+    int mosiGpio; ///< MOSI GPIO.
+    int sclkGpio; ///< SCLK GPIO.
+    int rstbGpio; ///< RESET# GPIO (active low).
+    int intbGpio; ///< INTB GPIO (optional status interrupt).
+};
+
+/**
+ * @brief    Si4684Driver — full Si4684 control over SPI (AN649 / PE5PVB).
+ *
+ * @dname    Si4684Driver
+ * @return   n/a (type)
+ * @pubstate Owns the SPI link and boot state. Register-level command bytes
+ *           stay private; callers use intent-level methods only.
+ *
+ * Implements the documented boot sequence plus band-specific tuning, property
+ * access, RSQ/DIGRAD reads, and DAB service selection.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+class Si4684Driver {
+public:
+    /**
+     * @brief    Si4684Driver — construct with board pins and firmware blobs.
+     *
+     * @dname    Si4684Driver
+     * @param    pins      Board SPI and GPIO wiring.
+     * @param    patch     ROM patch blob reader for HOST_LOAD.
+     * @param    dabImage  DAB application image reader.
+     * @param    fmImage   FM application image reader.
+     * @pubstate stores pin map and blob references; not booted until boot().
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    Si4684Driver(Si4684Pins pins,
+                 const core::IFirmwareBlobReader& patch,
+                 const core::IFirmwareBlobReader& dabImage,
+                 const core::IFirmwareBlobReader& fmImage);
+
+    /**
+     * @brief    ~Si4684Driver — release SPI resources.
+     *
+     * @dname    ~Si4684Driver
+     * @pubstate removes SPI device and bus when active.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    ~Si4684Driver();
+
+    Si4684Driver(const Si4684Driver&) = delete;
+    Si4684Driver& operator=(const Si4684Driver&) = delete;
+
+    /**
+     * @brief    boot — cold-start: load patch, image, and configure I/O.
+     *
+     * @dname    boot
+     * @param    band  DAB or FM application to load.
+     * @return   Ok on success, or Si4684Error.
+     * @pubstate writes booted_ and loadedBand_ on success.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, Si4684Error> boot(Si4684Band band);
+
+    /**
+     * @brief    isBooted — query whether boot completed successfully.
+     *
+     * @dname    isBooted
+     * @return   true after a successful boot().
+     * @pubstate reads booted_.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] bool isBooted() const noexcept;
+
+    /**
+     * @brief    loadedBand — read the active application band.
+     *
+     * @dname    loadedBand
+     * @return   Si4684Band loaded by the last successful boot().
+     * @pubstate reads loadedBand_.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] Si4684Band loadedBand() const noexcept;
+
+    /**
+     * @brief    getPartInfo — read chip identity and firmware revision.
+     *
+     * @dname    getPartInfo
+     * @return   Si4684PartInfo on success, or Si4684Error.
+     * @pubstate reads chip via GET_PART_INFO (AN649).
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<Si4684PartInfo, Si4684Error> getPartInfo();
+
+    /**
+     * @brief    getSysState — read the running application state.
+     *
+     * @dname    getSysState
+     * @return   Si4684SysState on success, or Si4684Error.
+     * @pubstate reads chip via GET_SYS_STATE.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<Si4684SysState, Si4684Error> getSysState();
+
+    /**
+     * @brief    setProperty — write a Skyworks property (SET_PROPERTY 0x13).
+     *
+     * @dname    setProperty
+     * @param    propertyId  16-bit property address.
+     * @param    value       16-bit property value.
+     * @return   Ok on success, or Si4684Error.
+     * @pubstate writes property via SPI command.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, Si4684Error> setProperty(
+        std::uint16_t propertyId, std::uint16_t value);
+
+    /**
+     * @brief    setVolume — set audio attenuator 0–63 (property 0x0300).
+     *
+     * @dname    setVolume
+     * @param    level  Attenuator level 0–63.
+     * @return   Ok on success, or Si4684Error.
+     * @pubstate writes AUDIO_VOLUME property.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, Si4684Error> setVolume(std::uint8_t level);
+
+    /**
+     * @brief    tuneFm — tune FM to a validated centre frequency.
+     *
+     * @dname    tuneFm
+     * @param    frequency  FM centre frequency in kHz.
+     * @return   Ok on success, or Si4684Error::WrongBand / TuneFailed.
+     * @pubstate sends FM_TUNE_FREQ and waits for STC (AN649).
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, Si4684Error> tuneFm(
+        core::FrequencyKHz frequency);
+
+    /**
+     * @brief    seekFm — seek FM in the given direction.
+     *
+     * @dname    seekFm
+     * @param    direction  Up or Down scan direction.
+     * @param    wrap       Band wrap behaviour for FM_SEEK_START.
+     * @return   New centre frequency on success, or Si4684Error.
+     * @pubstate sends FM_SEEK_START and waits for STC.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<core::FrequencyKHz, Si4684Error> seekFm(
+        core::SeekDirection direction, SeekBandWrap wrap);
+
+    /**
+     * @brief    readFmRsq — read FM signal quality metrics.
+     *
+     * @dname    readFmRsq
+     * @return   Si4684FmRsq on success, or Si4684Error.
+     * @pubstate reads FM_RSQ_STATUS response bytes.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<Si4684FmRsq, Si4684Error> readFmRsq();
+
+    /**
+     * @brief    readFmRds — read a raw RDS group snapshot.
+     *
+     * @dname    readFmRds
+     * @return   Si4684FmRdsStatus on success, or Si4684Error.
+     * @pubstate reads FM_RDS_STATUS response bytes.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<Si4684FmRdsStatus, Si4684Error> readFmRds();
+
+    /**
+     * @brief    installDefaultDabFrequencyPlan — load Band III frequency list.
+     *
+     * @dname    installDefaultDabFrequencyPlan
+     * @return   Ok on success, or Si4684Error.
+     * @pubstate sends DAB_SET_FREQ_LIST with kDefaultDabFrequencyKhz.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, Si4684Error> installDefaultDabFrequencyPlan();
+
+    /**
+     * @brief    tuneDab — tune to a Band III ensemble index.
+     *
+     * @dname    tuneDab
+     * @param    freqIndex  Ensemble index 0–37.
+     * @return   Ok on success, or Si4684Error.
+     * @pubstate sends DAB_TUNE_FREQ and waits for STC.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, Si4684Error> tuneDab(std::uint8_t freqIndex);
+
+    /**
+     * @brief    readDabDigRadStatus — read ensemble lock metrics.
+     *
+     * @dname    readDabDigRadStatus
+     * @return   Si4684DabDigRadStatus on success, or Si4684Error.
+     * @pubstate reads DAB_DIGRAD_STATUS response bytes.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<Si4684DabDigRadStatus, Si4684Error>
+    readDabDigRadStatus();
+
+    /**
+     * @brief    readDabEventStatus — read DAB event flags.
+     *
+     * @dname    readDabEventStatus
+     * @return   Si4684DabEventStatus on success, or Si4684Error.
+     * @pubstate reads DAB_GET_EVENT_STATUS response bytes.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<Si4684DabEventStatus, Si4684Error>
+    readDabEventStatus();
+
+    /**
+     * @brief    fetchDabServiceList — retrieve programmes for the ensemble.
+     *
+     * @dname    fetchDabServiceList
+     * @return   Service rows on success, or Si4684Error.
+     * @pubstate reads GET_DIGITAL_SERVICE_LIST chunks from the chip.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<std::vector<Si4684DabService>, Si4684Error>
+    fetchDabServiceList();
+
+    /**
+     * @brief    startDabService — start DAB audio for a programme.
+     *
+     * @dname    startDabService
+     * @param    serviceId    Selected service identifier.
+     * @param    componentId  Audio component within the service.
+     * @param    type         Digital service type (audio by default).
+     * @return   Ok on success, or Si4684Error.
+     * @pubstate sends START_DIGITAL_SERVICE.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, Si4684Error> startDabService(
+        std::uint32_t serviceId,
+        std::uint32_t componentId,
+        Si4684DigitalServiceType type = Si4684DigitalServiceType::Audio);
+
+private:
+    enum class Command : std::uint8_t {
+        PowerUp = 0x01,
+        HostLoad = 0x04,
+        LoadInit = 0x06,
+        BootCmd = 0x07,
+        GetPartInfo = 0x08,
+        GetSysState = 0x09,
+        GetFuncInfo = 0x12,
+        SetProperty = 0x13,
+        FmTuneFreq = 0x30,
+        FmSeekStart = 0x31,
+        FmRsqStatus = 0x32,
+        FmRdsStatus = 0x34,
+        GetDigitalServiceList = 0x80,
+        StartDigitalService = 0x81,
+        GetDigitalServiceData = 0x84,
+        DabTuneFreq = 0xB0,
+        DabDigRadStatus = 0xB2,
+        DabGetEventStatus = 0xB3,
+        DabSetFreqList = 0xB8,
+    };
+
+    [[nodiscard]] std::expected<void, Si4684Error> ensureBooted() const;
+    [[nodiscard]] std::expected<void, Si4684Error> ensureBand(
+        Si4684Band band) const;
+    [[nodiscard]] std::expected<void, Si4684Error> waitCts();
+    [[nodiscard]] std::expected<void, Si4684Error> waitStc();
+    [[nodiscard]] std::expected<void, Si4684Error> sendCommand(
+        std::span<const std::uint8_t> bytes);
+    [[nodiscard]] std::expected<void, Si4684Error> readRaw(
+        std::span<std::uint8_t> buffer);
+    [[nodiscard]] std::expected<void, Si4684Error> writeCommand(
+        Command cmd, const std::uint8_t* payload, std::size_t length);
+    [[nodiscard]] std::expected<void, Si4684Error> hostLoadBlob(
+        const core::IFirmwareBlobReader& blob, std::size_t chunkPayload);
+    [[nodiscard]] std::expected<void, Si4684Error> configureAfterBoot(
+        Si4684Band band);
+
+    Si4684Pins pins_;
+    const core::IFirmwareBlobReader& patch_;
+    const core::IFirmwareBlobReader& dabImage_;
+    const core::IFirmwareBlobReader& fmImage_;
+    bool booted_;
+    Si4684Band loadedBand_;
+    bool spiBusActive_;
+    void* spiDevice_;
+};
+
+} // namespace si4684

Software/components/drivers/si4684/include/si4684/Si4684EmbeddedImages.hpp

@@ -0,0 +1,100 @@
+/**
+ * @file    Si4684EmbeddedImages.hpp
+ * @brief   Embedded Si4684 ROM patch, DAB and FM firmware blob accessors.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#include "core/EmbeddedBlobReader.hpp"
+#include "si4684/Si4684Band.hpp"
+
+namespace si4684 {
+
+/**
+ * @brief    Si4684EmbeddedImages — flash-backed Si4684 firmware blobs.
+ *
+ * @dname    Si4684EmbeddedImages
+ * @return   n/a (type)
+ * @pubstate Owns EmbeddedBlobReader views over EMBED_FILES symbols from
+ *           Firmware/Si4684-Firmware/.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+class Si4684EmbeddedImages {
+public:
+    /**
+     * @brief    Si4684EmbeddedImages — bind linker-embedded binaries.
+     *
+     * @dname    Si4684EmbeddedImages
+     * @pubstate constructs patch_, dab_, and fm_ readers from flash symbols.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    Si4684EmbeddedImages();
+
+    /**
+     * @brief    romPatch — ROM patch blob for HOST_LOAD before main image.
+     *
+     * @dname    romPatch
+     * @return   Reader over rom_patch_016.bin.
+     * @pubstate reads patch_.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] const core::IFirmwareBlobReader& romPatch() const noexcept;
+
+    /**
+     * @brief    dabFirmware — DAB application image blob.
+     *
+     * @dname    dabFirmware
+     * @return   Reader over dab_firmware.bin.
+     * @pubstate reads dab_.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] const core::IFirmwareBlobReader& dabFirmware() const noexcept;
+
+    /**
+     * @brief    fmFirmware — FM application image blob.
+     *
+     * @dname    fmFirmware
+     * @return   Reader over fm_firmware.bin.
+     * @pubstate reads fm_.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] const core::IFirmwareBlobReader& fmFirmware() const noexcept;
+
+    /**
+     * @brief    applicationImage — map band to embedded application blob.
+     *
+     * @dname    applicationImage
+     * @param    band  DAB or FM image selector.
+     * @return   Reader for the selected application firmware.
+     * @pubstate reads dab_ or fm_.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] const core::IFirmwareBlobReader& applicationImage(
+        Si4684Band band) const noexcept;
+
+private:
+    core::EmbeddedBlobReader patch_;
+    core::EmbeddedBlobReader dab_;
+    core::EmbeddedBlobReader fm_;
+};
+
+} // namespace si4684

Software/components/drivers/si4684/include/si4684/Si4684Error.hpp

@@ -0,0 +1,44 @@
+/**
+ * @file    Si4684Error.hpp
+ * @brief   Typed errors for Si4684 driver operations.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+namespace si4684 {
+
+/**
+ * @brief    Si4684Error — failure causes for Si4684 bring-up and tuning.
+ *
+ * @dname    Si4684Error
+ * @return   n/a (type)
+ * @pubstate n/a
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+enum class Si4684Error {
+    SpiInitFailed,
+    ResetFailed,
+    CtsTimeout,
+    PowerUpFailed,
+    PatchLoadFailed,
+    ImageLoadFailed,
+    BootFailed,
+    NotBooted,
+    WrongBand,
+    CommandFailed,
+    StcTimeout,
+    TuneFailed,
+    ReplyTooShort,
+    BufferTooSmall,
+};
+
+} // namespace si4684

Software/components/drivers/si4684/include/si4684/Si4684Tuner.hpp

@@ -0,0 +1,195 @@
+/**
+ * @file    Si4684Tuner.hpp
+ * @brief   core::ITuner adapter over Si4684Driver.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#include "core/FrequencyKHz.hpp"
+#include "core/ITuner.hpp"
+#include "si4684/Si4684Driver.hpp"
+
+namespace si4684 {
+
+/**
+ * @brief    Si4684Tuner — maps Si4684Driver to core::ITuner.
+ *
+ * @dname    Si4684Tuner
+ * @param    driver  Borrowed Si4684Driver (must outlive this adapter).
+ * @return   n/a (type)
+ * @pubstate Borrows driver_. Caches last DAB index, FM frequency, and volume
+ *           for status reporting. No public data members.
+ *
+ * Translates domain calls into SPI commands and maps Si4684Error to
+ * core::TunerError at this boundary.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+class Si4684Tuner : public core::ITuner {
+public:
+    /**
+     * @brief    Si4684Tuner — bind to a booted or bootable driver instance.
+     *
+     * @dname    Si4684Tuner
+     * @param    driver  Si4684 driver constructed by HardwareBootstrap.
+     * @pubstate stores driver reference; sets default tune targets.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    explicit Si4684Tuner(Si4684Driver& driver);
+
+    /**
+     * @brief    boot — load the requested Si4684 application image.
+     *
+     * @dname    boot
+     * @param    band  DAB or FM image to load.
+     * @return   Ok on success, or a mapped TunerError.
+     * @pubstate delegates to driver_.boot().
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, core::TunerError> boot(
+        core::TunerBand band) override;
+
+    /**
+     * @brief    currentBand — read the loaded application band.
+     *
+     * @dname    currentBand
+     * @return   Active TunerBand, or TunerError::NotBooted.
+     * @pubstate reads driver_.loadedBand().
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<core::TunerBand, core::TunerError> currentBand()
+        const override;
+
+    /**
+     * @brief    readStatus — build a core TunerStatus from driver metrics.
+     *
+     * @dname    readStatus
+     * @return   TunerStatus on success, or a mapped TunerError.
+     * @pubstate reads driver_; refreshes cached tune targets from RSQ/DIGRAD.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<core::TunerStatus, core::TunerError> readStatus()
+        override;
+
+    /**
+     * @brief    tuneDab — tune to a Band III ensemble index.
+     *
+     * @dname    tuneDab
+     * @param    freqIndex  Ensemble index 0–37.
+     * @return   Ok on success, or a mapped TunerError.
+     * @pubstate writes dabIndex_ on success.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, core::TunerError> tuneDab(
+        std::uint8_t freqIndex) override;
+
+    /**
+     * @brief    tuneFm — tune to an FM centre frequency in kHz.
+     *
+     * @dname    tuneFm
+     * @param    frequency  Validated FM centre frequency.
+     * @return   Ok on success, or a mapped TunerError.
+     * @pubstate writes fmFrequency_ on success.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, core::TunerError> tuneFm(
+        core::FrequencyKHz frequency) override;
+
+    /**
+     * @brief    seekFm — seek FM with band wrap.
+     *
+     * @dname    seekFm
+     * @param    direction  Up or Down scan direction.
+     * @return   New centre frequency, or a mapped TunerError.
+     * @pubstate writes fmFrequency_ on success.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<core::FrequencyKHz, core::TunerError> seekFm(
+        core::SeekDirection direction) override;
+
+    /**
+     * @brief    listDabServices — fetch programmes for the current ensemble.
+     *
+     * @dname    listDabServices
+     * @return   Service entries, ServiceListEmpty, or a mapped TunerError.
+     * @pubstate reads driver_ service list when ready.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<std::vector<core::TunerServiceEntry>,
+                                    core::TunerError>
+    listDabServices() override;
+
+    /**
+     * @brief    playDabService — start DAB audio output.
+     *
+     * @dname    playDabService
+     * @param    serviceId    Selected service identifier.
+     * @param    componentId  Audio component within the service.
+     * @return   Ok on success, or a mapped TunerError.
+     * @pubstate delegates to driver_.startDabService().
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, core::TunerError> playDabService(
+        std::uint32_t serviceId, std::uint32_t componentId) override;
+
+    /**
+     * @brief    setVolume — set Si4684 output attenuation.
+     *
+     * @dname    setVolume
+     * @param    level  Attenuator 0–63.
+     * @return   Ok on success, or a mapped TunerError.
+     * @pubstate writes volume_ on success.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, core::TunerError> setVolume(
+        std::uint8_t level) override;
+
+private:
+    /**
+     * @brief    mapError — translate Si4684Error to core::TunerError.
+     *
+     * @dname    mapError
+     * @param    error  Driver-level failure cause.
+     * @return   Equivalent TunerError for services and HTTP layer.
+     * @pubstate none
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] static core::TunerError mapError(Si4684Error error) noexcept;
+
+    Si4684Driver& driver_;
+    std::uint8_t dabIndex_;
+    core::FrequencyKHz fmFrequency_;
+    std::uint8_t volume_;
+};
+
+} // namespace si4684

Software/components/drivers/si4684/include/si4684/Si4684Types.hpp

@@ -0,0 +1,176 @@
+/**
+ * @file    Si4684Types.hpp
+ * @brief   Domain types for Si4684 tuner operations (DAB/FM status, services).
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#include "core/FrequencyKHz.hpp"
+#include "core/SeekDirection.hpp"
+
+#include <array>
+#include <cstddef>
+#include <cstdint>
+
+namespace si4684 {
+
+/**
+ * @brief    Si4684DigitalServiceType — START_DIGITAL_SERVICE mode byte.
+ *
+ * @dname    Si4684DigitalServiceType
+ * @return   n/a (type)
+ * @pubstate n/a
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+enum class Si4684DigitalServiceType : std::uint8_t {
+    Audio = 0x00,
+    Packet = 0x01,
+};
+
+/**
+ * @brief    SeekBandWrap — FM seek band-wrap behaviour (FM_SEEK_START).
+ *
+ * @dname    SeekBandWrap
+ * @return   n/a (type)
+ * @pubstate n/a
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+enum class SeekBandWrap { Wrap, NoWrap };
+
+/**
+ * @brief    Si4684PartInfo — chip identity from GET_PART_INFO (AN649).
+ *
+ * @dname    Si4684PartInfo
+ * @return   n/a (type)
+ * @pubstate Plain DTO from GET_PART_INFO response bytes.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct Si4684PartInfo {
+    std::uint16_t chipId;         ///< Part identifier from the chip.
+    std::uint8_t firmwareMajor;   ///< Loaded firmware major version.
+    std::uint8_t firmwareMinor;   ///< Loaded firmware minor version.
+    std::uint8_t firmwareBuild;   ///< Loaded firmware build number.
+};
+
+/**
+ * @brief    Si4684SysState — running application after boot.
+ *
+ * @dname    Si4684SysState
+ * @return   n/a (type)
+ * @pubstate Plain DTO from GET_SYS_STATE.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct Si4684SysState {
+    std::uint8_t imageType; ///< Loaded image type byte from the chip.
+};
+
+/**
+ * @brief    Si4684FmRsq — FM received-signal quality (FM_RSQ_STATUS).
+ *
+ * @dname    Si4684FmRsq
+ * @return   n/a (type)
+ * @pubstate Plain DTO from FM_RSQ_STATUS response bytes.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct Si4684FmRsq {
+    core::FrequencyKHz frequency; ///< Tuned centre frequency in kHz.
+    std::int8_t rssiDbuV;         ///< RSSI in dBµV.
+    std::int8_t snrDb;            ///< SNR in dB.
+    bool valid;                   ///< RSQ valid flag from the chip.
+    bool stereo;                  ///< Stereo pilot detected.
+};
+
+/**
+ * @brief    Si4684FmRdsStatus — raw RDS group snapshot (FM_RDS_STATUS).
+ *
+ * @dname    Si4684FmRdsStatus
+ * @return   n/a (type)
+ * @pubstate Plain DTO from FM_RDS_STATUS response bytes.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct Si4684FmRdsStatus {
+    std::uint16_t blockA; ///< RDS block A.
+    std::uint16_t blockB; ///< RDS block B.
+    std::uint16_t blockC; ///< RDS block C.
+    std::uint16_t blockD; ///< RDS block D.
+    bool received;        ///< Group received flag.
+};
+
+/**
+ * @brief    Si4684DabDigRadStatus — ensemble lock metrics (DAB_DIGRAD_STATUS).
+ *
+ * @dname    Si4684DabDigRadStatus
+ * @return   n/a (type)
+ * @pubstate Plain DTO from DAB_DIGRAD_STATUS response bytes.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct Si4684DabDigRadStatus {
+    std::uint8_t ficQuality; ///< FIC quality 0–100.
+    std::uint8_t cnrDb;      ///< CNR in dB.
+    bool acquired;           ///< Ensemble acquired flag.
+    bool valid;              ///< DIGRAD valid flag.
+};
+
+/**
+ * @brief    Si4684DabEventStatus — DAB event flags (DAB_GET_EVENT_STATUS).
+ *
+ * @dname    Si4684DabEventStatus
+ * @return   n/a (type)
+ * @pubstate Plain DTO from DAB_GET_EVENT_STATUS response bytes.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct Si4684DabEventStatus {
+    bool serviceListReady; ///< Service list available for fetch.
+    bool reconfig;         ///< Ensemble reconfiguration event.
+};
+
+/**
+ * @brief    Si4684DabService — one row from GET_DIGITAL_SERVICE_LIST.
+ *
+ * @dname    Si4684DabService
+ * @return   n/a (type)
+ * @pubstate Plain DTO parsed from a service-list chunk.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct Si4684DabService {
+    std::uint32_t serviceId;    ///< DAB service identifier.
+    std::uint32_t componentId;  ///< Audio component identifier.
+    std::array<char, 17> label; ///< Programme label, NUL-terminated.
+    std::uint8_t serviceType;   ///< Service type byte from the list.
+};
+
+/** Band III DAB channel plan (kHz), PE5PVB / ETSI EN 300 401 Table 14. */
+inline constexpr std::array<std::uint32_t, 38> kDefaultDabFrequencyKhz = {
+    174928, 176640, 178352, 180064, 181936, 183648, 185360, 187072, 188928,
+    190640, 192352, 194064, 195936, 197648, 199360, 201072, 202928, 204640,
+    206352, 208064, 209936, 211648, 213360, 215072, 216928, 218640, 220352,
+    222064, 223936, 225648, 227360, 229072, 230784, 232496, 234208, 235776,
+    237488, 239200,
+};
+
+} // namespace si4684

Software/components/drivers/si4684/src/Si4684Driver.cpp

@@ -0,0 +1,776 @@
+/**
+ * @file    Si4684Driver.cpp
+ * @brief   Si4684Driver implementation.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "si4684/Si4684Driver.hpp"
+
+#include "driver/gpio.h"
+#include "driver/spi_master.h"
+#include "esp_log.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+
+#include <algorithm>
+#include <array>
+#include <cstring>
+#include <span>
+
+namespace si4684 {
+
+namespace {
+
+constexpr char kTag[] = "Si4684";
+constexpr std::size_t kSpiBufferSize = 4096U;
+constexpr int kCtsPollMs = 2;
+constexpr int kCtsRetries = 200;
+constexpr int kStcRetries = 250;
+constexpr int kStcPollMs = 20;
+
+constexpr std::uint16_t kPropDigitalIoOutputSelect = 0x0200U;
+constexpr std::uint16_t kPropDigitalIoSampleRate = 0x0201U;
+constexpr std::uint16_t kPropPinConfigEnable = 0x0800U;
+constexpr std::uint16_t kPropAudioVolume = 0x0300U;
+constexpr std::uint16_t kPropFmRdsConfig = 0x3C02U;
+constexpr std::uint16_t kPropDabTuneFeCfg = 0x1712U;
+constexpr std::uint16_t kPropDabXpadEnable = 0xB400U;
+constexpr std::uint16_t kPropDigitalServiceIntSource = 0x8100U;
+
+std::uint16_t readLe16(const std::uint8_t* p)
+{
+    return static_cast<std::uint16_t>(p[0] | (static_cast<std::uint16_t>(p[1]) << 8));
+}
+
+std::uint32_t readLe32(const std::uint8_t* p)
+{
+    return static_cast<std::uint32_t>(p[0])
+           | (static_cast<std::uint32_t>(p[1]) << 8)
+           | (static_cast<std::uint32_t>(p[2]) << 16)
+           | (static_cast<std::uint32_t>(p[3]) << 24);
+}
+
+/** FM_TUNE_FREQ uses 10 kHz units (AN649); API uses kHz. */
+[[nodiscard]] std::uint16_t kHzToChipFmFreq(std::uint32_t frequencyKhz)
+{
+    return static_cast<std::uint16_t>(frequencyKhz / 10U);
+}
+
+[[nodiscard]] std::uint32_t chipFmFreqToKHz(std::uint16_t chipFreq)
+{
+    return static_cast<std::uint32_t>(chipFreq) * 10U;
+}
+
+} // namespace
+
+Si4684Driver::Si4684Driver(Si4684Pins pins,
+                           const core::IFirmwareBlobReader& patch,
+                           const core::IFirmwareBlobReader& dabImage,
+                           const core::IFirmwareBlobReader& fmImage)
+    : pins_(pins)
+    , patch_(patch)
+    , dabImage_(dabImage)
+    , fmImage_(fmImage)
+    , booted_(false)
+    , loadedBand_(Si4684Band::Dab)
+    , spiBusActive_(false)
+    , spiDevice_(nullptr)
+{
+}
+
+Si4684Driver::~Si4684Driver()
+{
+    if (spiDevice_ != nullptr) {
+        spi_bus_remove_device(static_cast<spi_device_handle_t>(spiDevice_));
+        spiDevice_ = nullptr;
+    }
+    if (spiBusActive_) {
+        spi_bus_free(static_cast<spi_host_device_t>(pins_.spiHost));
+        spiBusActive_ = false;
+    }
+}
+
+std::expected<void, Si4684Error> Si4684Driver::ensureBooted() const
+{
+    if (!booted_) {
+        return std::unexpected(Si4684Error::NotBooted);
+    }
+    return {};
+}
+
+std::expected<void, Si4684Error> Si4684Driver::ensureBand(
+    Si4684Band band) const
+{
+    if (auto ready = ensureBooted(); !ready) {
+        return ready;
+    }
+    if (loadedBand_ != band) {
+        return std::unexpected(Si4684Error::WrongBand);
+    }
+    return {};
+}
+
+std::expected<void, Si4684Error> Si4684Driver::waitCts()
+{
+    std::array<std::uint8_t, 5> pollTx = {};
+    std::array<std::uint8_t, 5> pollRx = {};
+
+    for (int attempt = 0; attempt < kCtsRetries; ++attempt) {
+        vTaskDelay(pdMS_TO_TICKS(kCtsPollMs));
+        spi_transaction_t txn = {};
+        txn.length = pollTx.size() * 8U;
+        txn.tx_buffer = pollTx.data();
+        txn.rx_buffer = pollRx.data();
+        if (spi_device_transmit(static_cast<spi_device_handle_t>(spiDevice_),
+                                &txn) != ESP_OK) {
+            return std::unexpected(Si4684Error::SpiInitFailed);
+        }
+        if ((pollRx[1] & 0x80U) != 0U) {
+            return {};
+        }
+    }
+    return std::unexpected(Si4684Error::CtsTimeout);
+}
+
+std::expected<void, Si4684Error> Si4684Driver::waitStc()
+{
+    std::array<std::uint8_t, 5> pollTx = {};
+    std::array<std::uint8_t, 5> pollRx = {};
+
+    for (int attempt = 0; attempt < kStcRetries; ++attempt) {
+        vTaskDelay(pdMS_TO_TICKS(kStcPollMs));
+        spi_transaction_t txn = {};
+        txn.length = pollTx.size() * 8U;
+        txn.tx_buffer = pollTx.data();
+        txn.rx_buffer = pollRx.data();
+        if (spi_device_transmit(static_cast<spi_device_handle_t>(spiDevice_),
+                                &txn) != ESP_OK) {
+            return std::unexpected(Si4684Error::SpiInitFailed);
+        }
+        if ((pollRx[1] & 0x01U) != 0U) {
+            return {};
+        }
+    }
+    return std::unexpected(Si4684Error::StcTimeout);
+}
+
+std::expected<void, Si4684Error> Si4684Driver::sendCommand(
+    std::span<const std::uint8_t> bytes)
+{
+    if (bytes.empty() || bytes.size() > kSpiBufferSize) {
+        return std::unexpected(Si4684Error::CommandFailed);
+    }
+    spi_transaction_t txn = {};
+    txn.length = bytes.size() * 8U;
+    txn.tx_buffer = bytes.data();
+    if (spi_device_transmit(static_cast<spi_device_handle_t>(spiDevice_),
+                            &txn) != ESP_OK) {
+        return std::unexpected(Si4684Error::SpiInitFailed);
+    }
+    return waitCts();
+}
+
+std::expected<void, Si4684Error> Si4684Driver::readRaw(
+    std::span<std::uint8_t> buffer)
+{
+    if (buffer.empty() || buffer.size() > kSpiBufferSize) {
+        return std::unexpected(Si4684Error::ReplyTooShort);
+    }
+    std::fill(buffer.begin(), buffer.end(), 0U);
+    spi_transaction_t txn = {};
+    txn.length = buffer.size() * 8U;
+    txn.tx_buffer = buffer.data();
+    txn.rx_buffer = buffer.data();
+    if (spi_device_transmit(static_cast<spi_device_handle_t>(spiDevice_),
+                            &txn) != ESP_OK) {
+        return std::unexpected(Si4684Error::SpiInitFailed);
+    }
+    return {};
+}
+
+std::expected<void, Si4684Error> Si4684Driver::writeCommand(
+    Command cmd, const std::uint8_t* payload, std::size_t length)
+{
+    if (length + 2U > kSpiBufferSize) {
+        return std::unexpected(Si4684Error::CommandFailed);
+    }
+    std::array<std::uint8_t, kSpiBufferSize> buffer = {};
+    buffer[0] = static_cast<std::uint8_t>(cmd);
+    buffer[1] = 0x00U;
+    if (payload != nullptr && length > 0U) {
+        std::memcpy(buffer.data() + 2U, payload, length);
+    }
+    return sendCommand({buffer.data(), 2U + length});
+}
+
+std::expected<void, Si4684Error> Si4684Driver::hostLoadBlob(
+    const core::IFirmwareBlobReader& blob, std::size_t chunkPayload)
+{
+    std::array<std::byte, 2044> payload = {};
+    std::size_t offset = 0U;
+
+    while (offset < blob.size()) {
+        const std::size_t maxChunk = std::min(chunkPayload, payload.size());
+        const std::size_t copied =
+            blob.read(offset, std::span<std::byte>(payload.data(), maxChunk));
+        if (copied == 0U) {
+            return std::unexpected(Si4684Error::ImageLoadFailed);
+        }
+
+        std::array<std::uint8_t, kSpiBufferSize> tx = {};
+        tx[0] = static_cast<std::uint8_t>(Command::HostLoad);
+        tx[1] = 0x00U;
+        tx[2] = 0x00U;
+        tx[3] = 0x00U;
+        std::memcpy(tx.data() + 4U, payload.data(), copied);
+
+        spi_transaction_t txn = {};
+        txn.length = (4U + copied) * 8U;
+        txn.tx_buffer = tx.data();
+        if (spi_device_transmit(static_cast<spi_device_handle_t>(spiDevice_),
+                                &txn) != ESP_OK) {
+            return std::unexpected(Si4684Error::ImageLoadFailed);
+        }
+        if (auto cts = waitCts(); !cts) {
+            return cts;
+        }
+        offset += copied;
+    }
+    return {};
+}
+
+std::expected<void, Si4684Error> Si4684Driver::setProperty(
+    std::uint16_t propertyId, std::uint16_t value)
+{
+    if (auto ready = ensureBooted(); !ready) {
+        return ready;
+    }
+    const std::uint8_t args[] = {
+        static_cast<std::uint8_t>(propertyId & 0xFFU),
+        static_cast<std::uint8_t>(propertyId >> 8),
+        static_cast<std::uint8_t>(value & 0xFFU),
+        static_cast<std::uint8_t>(value >> 8),
+    };
+    if (auto cmd = writeCommand(Command::SetProperty, args, sizeof(args));
+        !cmd) {
+        return std::unexpected(Si4684Error::CommandFailed);
+    }
+    return {};
+}
+
+std::expected<void, Si4684Error> Si4684Driver::setVolume(std::uint8_t level)
+{
+    return setProperty(kPropAudioVolume,
+                       static_cast<std::uint16_t>(level & 0x3FU));
+}
+
+std::expected<Si4684PartInfo, Si4684Error> Si4684Driver::getPartInfo()
+{
+    if (auto ready = ensureBooted(); !ready) {
+        return std::unexpected(ready.error());
+    }
+    if (auto cmd = writeCommand(Command::GetPartInfo, nullptr, 0U); !cmd) {
+        return std::unexpected(Si4684Error::CommandFailed);
+    }
+    std::array<std::uint8_t, 24> raw = {};
+    if (auto rd = readRaw(raw); !rd) {
+        return std::unexpected(rd.error());
+    }
+    if (auto fn = writeCommand(Command::GetFuncInfo, nullptr, 0U); !fn) {
+        return std::unexpected(Si4684Error::CommandFailed);
+    }
+    std::array<std::uint8_t, 13> fnRaw = {};
+    if (auto rd = readRaw(fnRaw); !rd) {
+        return std::unexpected(rd.error());
+    }
+
+    Si4684PartInfo info = {};
+    info.chipId = readLe16(raw.data() + 9);
+    info.firmwareMajor = fnRaw[5];
+    info.firmwareMinor = fnRaw[6];
+    info.firmwareBuild = fnRaw[7];
+    return info;
+}
+
+std::expected<Si4684SysState, Si4684Error> Si4684Driver::getSysState()
+{
+    if (auto ready = ensureBooted(); !ready) {
+        return std::unexpected(ready.error());
+    }
+    if (auto cmd = writeCommand(Command::GetSysState, nullptr, 0U); !cmd) {
+        return std::unexpected(Si4684Error::CommandFailed);
+    }
+    std::array<std::uint8_t, 7> raw = {};
+    if (auto rd = readRaw(raw); !rd) {
+        return std::unexpected(rd.error());
+    }
+    Si4684SysState state = {};
+    state.imageType = raw[5];
+    return state;
+}
+
+std::expected<void, Si4684Error> Si4684Driver::configureAfterBoot(
+    Si4684Band band)
+{
+    if (band == Si4684Band::Dab) {
+        if (auto plan = installDefaultDabFrequencyPlan(); !plan) {
+            return plan;
+        }
+        static constexpr std::uint16_t kDabProps[][2] = {
+            {0x0202U, 0x1600U},
+            {0x1710U, 0xFC4AU},
+            {0x1711U, 0x00F8U},
+            {0x8101U, 0x0064U},
+            {0xB200U, 0x0000U},
+            {0xB201U, 0x0080U},
+            {0xB301U, 0x0000U},
+            {0xB302U, 0x0000U},
+            {0xB303U, 0x0000U},
+            {0xB401U, 0x0002U},
+            {0xB500U, 0x0000U},
+        };
+        for (const auto& prop : kDabProps) {
+            if (auto set = setProperty(prop[0], prop[1]); !set) {
+                return set;
+            }
+        }
+        if (auto xpad = setProperty(kPropDabXpadEnable, 0x0097U); !xpad) {
+            return xpad;
+        }
+    } else {
+        if (auto rds = setProperty(kPropFmRdsConfig, 0x0001U); !rds) {
+            return rds;
+        }
+    }
+
+    if (auto i2s = setProperty(kPropDigitalIoOutputSelect, 0x8000U); !i2s) {
+        return i2s;
+    }
+    if (auto rate = setProperty(kPropDigitalIoSampleRate, 0xAC44U); !rate) {
+        return rate;
+    }
+    if (auto pins = setProperty(kPropPinConfigEnable, 0x0003U); !pins) {
+        return pins;
+    }
+    if (auto dabFe = setProperty(kPropDabTuneFeCfg, 0x0001U); !dabFe) {
+        return dabFe;
+    }
+    if (auto dsrv = setProperty(kPropDigitalServiceIntSource, 0x0001U);
+        !dsrv) {
+        return dsrv;
+    }
+    return {};
+}
+
+std::expected<void, Si4684Error> Si4684Driver::boot(Si4684Band band)
+{
+    if (booted_ && loadedBand_ == band) {
+        return {};
+    }
+
+    if (booted_) {
+        booted_ = false;
+        if (spiDevice_ != nullptr) {
+            spi_bus_remove_device(static_cast<spi_device_handle_t>(spiDevice_));
+            spiDevice_ = nullptr;
+        }
+    }
+
+    const core::IFirmwareBlobReader& image =
+        (band == Si4684Band::Fm) ? fmImage_ : dabImage_;
+
+    gpio_config_t rstCfg = {};
+    rstCfg.pin_bit_mask = 1ULL << pins_.rstbGpio;
+    rstCfg.mode = GPIO_MODE_OUTPUT;
+    if (gpio_config(&rstCfg) != ESP_OK) {
+        return std::unexpected(Si4684Error::ResetFailed);
+    }
+    gpio_set_level(static_cast<gpio_num_t>(pins_.rstbGpio), 0);
+    vTaskDelay(pdMS_TO_TICKS(5));
+    gpio_set_level(static_cast<gpio_num_t>(pins_.rstbGpio), 1);
+    vTaskDelay(pdMS_TO_TICKS(3));
+
+    if (!spiBusActive_) {
+        spi_bus_config_t busCfg = {};
+        busCfg.miso_io_num = pins_.misoGpio;
+        busCfg.mosi_io_num = pins_.mosiGpio;
+        busCfg.sclk_io_num = pins_.sclkGpio;
+        busCfg.quadwp_io_num = -1;
+        busCfg.quadhd_io_num = -1;
+        busCfg.max_transfer_sz = static_cast<int>(kSpiBufferSize);
+
+        if (spi_bus_initialize(static_cast<spi_host_device_t>(pins_.spiHost),
+                               &busCfg, SPI_DMA_CH_AUTO) != ESP_OK) {
+            return std::unexpected(Si4684Error::SpiInitFailed);
+        }
+        spiBusActive_ = true;
+    }
+
+    if (spiDevice_ == nullptr) {
+        spi_device_interface_config_t devCfg = {};
+        devCfg.clock_speed_hz = 10 * 1000 * 1000;
+        devCfg.mode = 0;
+        devCfg.spics_io_num = pins_.csGpio;
+        devCfg.queue_size = 1;
+
+        spi_device_handle_t dev = nullptr;
+        if (spi_bus_add_device(static_cast<spi_host_device_t>(pins_.spiHost),
+                               &devCfg, &dev) != ESP_OK) {
+            return std::unexpected(Si4684Error::SpiInitFailed);
+        }
+        spiDevice_ = dev;
+    }
+
+    if (auto st = writeCommand(Command::GetSysState, nullptr, 0U); !st) {
+        return st;
+    }
+
+    const std::uint8_t powerUp[] = {
+        0x17, 0x48, 0x00, 0xf8, 0x24, 0x01, 0x1F, 0x10,
+        0x00, 0x00, 0x00, 0x18, 0x00, 0x00,
+    };
+    if (auto pu = writeCommand(Command::PowerUp, powerUp, sizeof(powerUp));
+        !pu) {
+        return std::unexpected(Si4684Error::PowerUpFailed);
+    }
+
+    vTaskDelay(pdMS_TO_TICKS(1));
+
+    if (auto li = writeCommand(Command::LoadInit, nullptr, 0U); !li) {
+        return std::unexpected(Si4684Error::PatchLoadFailed);
+    }
+
+    if (auto patch = hostLoadBlob(patch_, 124U); !patch) {
+        return std::unexpected(Si4684Error::PatchLoadFailed);
+    }
+
+    vTaskDelay(pdMS_TO_TICKS(4));
+
+    if (auto li2 = writeCommand(Command::LoadInit, nullptr, 0U); !li2) {
+        return std::unexpected(Si4684Error::ImageLoadFailed);
+    }
+
+    if (auto fw = hostLoadBlob(image, 2044U); !fw) {
+        return std::unexpected(Si4684Error::ImageLoadFailed);
+    }
+
+    if (auto bootCmd = writeCommand(Command::BootCmd, nullptr, 0U); !bootCmd) {
+        return std::unexpected(Si4684Error::BootFailed);
+    }
+
+    booted_ = true;
+    loadedBand_ = band;
+
+    if (auto cfg = configureAfterBoot(band); !cfg) {
+        booted_ = false;
+        return cfg;
+    }
+
+    ESP_LOGI(kTag, "%s firmware booted",
+             band == Si4684Band::Fm ? "FM" : "DAB");
+    return {};
+}
+
+bool Si4684Driver::isBooted() const noexcept
+{
+    return booted_;
+}
+
+Si4684Band Si4684Driver::loadedBand() const noexcept
+{
+    return loadedBand_;
+}
+
+std::expected<void, Si4684Error> Si4684Driver::tuneFm(
+    core::FrequencyKHz frequency)
+{
+    if (auto band = ensureBand(Si4684Band::Fm); !band) {
+        return band;
+    }
+    const std::uint16_t chipFreq = kHzToChipFmFreq(frequency.value());
+    const std::uint8_t args[] = {
+        0x00U,
+        static_cast<std::uint8_t>(chipFreq & 0xFFU),
+        static_cast<std::uint8_t>(chipFreq >> 8),
+        0x00U,
+        0x00U,
+    };
+    if (auto cmd = writeCommand(Command::FmTuneFreq, args, sizeof(args));
+        !cmd) {
+        return std::unexpected(Si4684Error::TuneFailed);
+    }
+    if (auto stc = waitStc(); !stc) {
+        return stc;
+    }
+    return {};
+}
+
+std::expected<core::FrequencyKHz, Si4684Error> Si4684Driver::seekFm(
+    core::SeekDirection direction, SeekBandWrap wrap)
+{
+    if (auto band = ensureBand(Si4684Band::Fm); !band) {
+        return std::unexpected(band.error());
+    }
+    const bool seekUp = direction == core::SeekDirection::Up;
+    const bool wrapBand = wrap == SeekBandWrap::Wrap;
+    const std::uint8_t args[] = {
+        0x10U,
+        static_cast<std::uint8_t>(((seekUp ? 1U : 0U) << 1U) | (wrapBand ? 1U : 0U)),
+        0x00U,
+        0x00U,
+        0x00U,
+    };
+    if (auto cmd = writeCommand(Command::FmSeekStart, args, sizeof(args));
+        !cmd) {
+        return std::unexpected(Si4684Error::TuneFailed);
+    }
+    if (auto stc = waitStc(); !stc) {
+        return std::unexpected(stc.error());
+    }
+    auto rsq = readFmRsq();
+    if (!rsq) {
+        return std::unexpected(rsq.error());
+    }
+    return rsq->frequency;
+}
+
+std::expected<Si4684FmRsq, Si4684Error> Si4684Driver::readFmRsq()
+{
+    if (auto band = ensureBand(Si4684Band::Fm); !band) {
+        return std::unexpected(band.error());
+    }
+    const std::uint8_t args[] = {0x00U};
+    if (auto cmd = writeCommand(Command::FmRsqStatus, args, sizeof(args));
+        !cmd) {
+        return std::unexpected(Si4684Error::CommandFailed);
+    }
+    std::array<std::uint8_t, 23> raw = {};
+    if (auto rd = readRaw(raw); !rd) {
+        return std::unexpected(rd.error());
+    }
+
+    Si4684FmRsq rsq = {};
+    const auto khz = chipFmFreqToKHz(readLe16(raw.data() + 6));
+    if (auto freq = core::FrequencyKHz::tryFromKhz(khz); freq) {
+        rsq.frequency = *freq;
+    } else {
+        return std::unexpected(Si4684Error::CommandFailed);
+    }
+    rsq.valid = (raw[4] & 0x01U) != 0U;
+    rsq.stereo = (raw[4] & 0x02U) != 0U;
+    rsq.rssiDbuV = static_cast<std::int8_t>(raw[8]);
+    rsq.snrDb = static_cast<std::int8_t>(raw[9]);
+    return rsq;
+}
+
+std::expected<Si4684FmRdsStatus, Si4684Error> Si4684Driver::readFmRds()
+{
+    if (auto band = ensureBand(Si4684Band::Fm); !band) {
+        return std::unexpected(band.error());
+    }
+    const std::uint8_t args[] = {0x01U};
+    if (auto cmd = writeCommand(Command::FmRdsStatus, args, sizeof(args));
+        !cmd) {
+        return std::unexpected(Si4684Error::CommandFailed);
+    }
+    std::array<std::uint8_t, 21> raw = {};
+    if (auto rd = readRaw(raw); !rd) {
+        return std::unexpected(rd.error());
+    }
+
+    Si4684FmRdsStatus rds = {};
+    rds.received = (raw[4] & 0x01U) != 0U;
+    rds.blockA = readLe16(raw.data() + 12);
+    rds.blockB = readLe16(raw.data() + 14);
+    rds.blockC = readLe16(raw.data() + 16);
+    rds.blockD = readLe16(raw.data() + 18);
+    return rds;
+}
+
+std::expected<void, Si4684Error> Si4684Driver::installDefaultDabFrequencyPlan()
+{
+    if (auto band = ensureBand(Si4684Band::Dab); !band) {
+        return band;
+    }
+
+    std::array<std::uint8_t, 4U + kDefaultDabFrequencyKhz.size() * 4U> cmd =
+        {};
+    cmd[0] = static_cast<std::uint8_t>(Command::DabSetFreqList);
+    cmd[1] = static_cast<std::uint8_t>(kDefaultDabFrequencyKhz.size());
+    cmd[2] = 0x00U;
+    cmd[3] = 0x00U;
+    for (std::size_t i = 0; i < kDefaultDabFrequencyKhz.size(); ++i) {
+        const std::uint32_t hz = kDefaultDabFrequencyKhz[i];
+        const std::size_t off = 4U + i * 4U;
+        cmd[off] = static_cast<std::uint8_t>(hz & 0xFFU);
+        cmd[off + 1] = static_cast<std::uint8_t>((hz >> 8) & 0xFFU);
+        cmd[off + 2] = static_cast<std::uint8_t>((hz >> 16) & 0xFFU);
+        cmd[off + 3] = static_cast<std::uint8_t>(hz >> 24);
+    }
+    return sendCommand(cmd);
+}
+
+std::expected<void, Si4684Error> Si4684Driver::tuneDab(std::uint8_t freqIndex)
+{
+    if (auto band = ensureBand(Si4684Band::Dab); !band) {
+        return band;
+    }
+    if (freqIndex >= kDefaultDabFrequencyKhz.size()) {
+        return std::unexpected(Si4684Error::TuneFailed);
+    }
+    const std::uint8_t args[] = {0x00U, freqIndex, 0x00U, 0x00U, 0x00U};
+    if (auto cmd = writeCommand(Command::DabTuneFreq, args, sizeof(args));
+        !cmd) {
+        return std::unexpected(Si4684Error::TuneFailed);
+    }
+    if (auto stc = waitStc(); !stc) {
+        return stc;
+    }
+    return {};
+}
+
+std::expected<Si4684DabDigRadStatus, Si4684Error>
+Si4684Driver::readDabDigRadStatus()
+{
+    if (auto band = ensureBand(Si4684Band::Dab); !band) {
+        return std::unexpected(band.error());
+    }
+    const std::uint8_t args[] = {0x01U};
+    if (auto cmd =
+            writeCommand(Command::DabDigRadStatus, args, sizeof(args));
+        !cmd) {
+        return std::unexpected(Si4684Error::CommandFailed);
+    }
+    std::array<std::uint8_t, 20> raw = {};
+    if (auto rd = readRaw(raw); !rd) {
+        return std::unexpected(rd.error());
+    }
+
+    Si4684DabDigRadStatus status = {};
+    status.ficQuality = raw[9];
+    status.cnrDb = raw[10];
+    status.acquired = (raw[4] & 0x08U) != 0U;
+    status.valid = status.ficQuality > 0U;
+    return status;
+}
+
+std::expected<Si4684DabEventStatus, Si4684Error>
+Si4684Driver::readDabEventStatus()
+{
+    if (auto band = ensureBand(Si4684Band::Dab); !band) {
+        return std::unexpected(band.error());
+    }
+    const std::uint8_t args[] = {0x00U};
+    if (auto cmd =
+            writeCommand(Command::DabGetEventStatus, args, sizeof(args));
+        !cmd) {
+        return std::unexpected(Si4684Error::CommandFailed);
+    }
+    std::array<std::uint8_t, 9> raw = {};
+    if (auto rd = readRaw(raw); !rd) {
+        return std::unexpected(rd.error());
+    }
+
+    Si4684DabEventStatus events = {};
+    events.serviceListReady = (raw[4] & 0x01U) != 0U;
+    events.reconfig = (raw[4] & 0x02U) != 0U;
+    return events;
+}
+
+std::expected<std::vector<Si4684DabService>, Si4684Error>
+Si4684Driver::fetchDabServiceList()
+{
+    if (auto band = ensureBand(Si4684Band::Dab); !band) {
+        return std::unexpected(band.error());
+    }
+
+    const std::uint8_t args[] = {0x00U};
+    if (auto cmd = writeCommand(Command::GetDigitalServiceList, args,
+                                sizeof(args));
+        !cmd) {
+        return std::unexpected(Si4684Error::CommandFailed);
+    }
+
+    std::array<std::uint8_t, 9> header = {};
+    if (auto rd = readRaw(header); !rd) {
+        return std::unexpected(rd.error());
+    }
+
+    const std::uint16_t payloadSize = readLe16(header.data() + 5);
+    if (payloadSize == 0U || payloadSize + 6U > kSpiBufferSize) {
+        return std::unexpected(Si4684Error::ReplyTooShort);
+    }
+
+    std::vector<std::uint8_t> body(payloadSize + 6U, 0U);
+    if (auto rd = readRaw(body); !rd) {
+        return std::unexpected(rd.error());
+    }
+
+    const std::uint8_t serviceCount = body[9];
+    std::vector<Si4684DabService> services;
+    services.reserve(serviceCount);
+
+    std::size_t offset = 13U;
+    for (std::uint8_t i = 0; i < serviceCount; ++i) {
+        if (offset + 24U > body.size()) {
+            break;
+        }
+        Si4684DabService entry = {};
+        entry.serviceId = readLe32(body.data() + offset);
+        offset += 4U;
+        entry.serviceType = body[offset] & 0x3FU;
+        const std::uint8_t componentCount = body[offset + 1] & 0x0FU;
+        offset += 4U;
+        std::memcpy(entry.label.data(), body.data() + offset, 16U);
+        entry.label[16] = '\0';
+        offset += 16U;
+
+        if (componentCount > 0U && offset + 4U <= body.size()) {
+            entry.componentId = readLe32(body.data() + offset);
+            offset += 4U;
+            if (offset < body.size()) {
+                ++offset;
+            }
+        }
+        services.push_back(entry);
+    }
+    return services;
+}
+
+std::expected<void, Si4684Error> Si4684Driver::startDabService(
+    std::uint32_t serviceId,
+    std::uint32_t componentId,
+    Si4684DigitalServiceType type)
+{
+    if (auto band = ensureBand(Si4684Band::Dab); !band) {
+        return band;
+    }
+    const std::uint8_t args[] = {
+        static_cast<std::uint8_t>(type),
+        0x00U,
+        0x00U,
+        static_cast<std::uint8_t>(serviceId & 0xFFU),
+        static_cast<std::uint8_t>((serviceId >> 8) & 0xFFU),
+        static_cast<std::uint8_t>((serviceId >> 16) & 0xFFU),
+        static_cast<std::uint8_t>(serviceId >> 24),
+        static_cast<std::uint8_t>(componentId & 0xFFU),
+        static_cast<std::uint8_t>((componentId >> 8) & 0xFFU),
+        static_cast<std::uint8_t>((componentId >> 16) & 0xFFU),
+        static_cast<std::uint8_t>(componentId >> 24),
+    };
+    if (auto cmd =
+            writeCommand(Command::StartDigitalService, args, sizeof(args));
+        !cmd) {
+        return std::unexpected(Si4684Error::CommandFailed);
+    }
+    return {};
+}
+
+} // namespace si4684

Software/components/drivers/si4684/src/Si4684EmbeddedImages.cpp

@@ -0,0 +1,89 @@
+/**
+ * @file    Si4684EmbeddedImages.cpp
+ * @brief   Si4684EmbeddedImages implementation.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "si4684/Si4684EmbeddedImages.hpp"
+
+#include <cstddef>
+#include <cstdint>
+
+/** @cond linker_symbols */
+extern "C" {
+extern const std::uint8_t rom_patch_016_bin_start[]
+    asm("_binary_rom_patch_016_bin_start");
+extern const std::uint8_t rom_patch_016_bin_end[]
+    asm("_binary_rom_patch_016_bin_end");
+extern const std::uint8_t dab_firmware_bin_start[]
+    asm("_binary_dab_firmware_bin_start");
+extern const std::uint8_t dab_firmware_bin_end[]
+    asm("_binary_dab_firmware_bin_end");
+extern const std::uint8_t fm_firmware_bin_start[]
+    asm("_binary_fm_firmware_bin_start");
+extern const std::uint8_t fm_firmware_bin_end[]
+    asm("_binary_fm_firmware_bin_end");
+}
+/** @endcond */
+
+namespace si4684 {
+
+namespace {
+
+const std::byte* asBytes(const std::uint8_t* ptr)
+{
+    return reinterpret_cast<const std::byte*>(ptr);
+}
+
+std::size_t embeddedSize(const std::uint8_t* start, const std::uint8_t* end)
+{
+    return static_cast<std::size_t>(end - start);
+}
+
+} // namespace
+
+Si4684EmbeddedImages::Si4684EmbeddedImages()
+    : patch_(asBytes(rom_patch_016_bin_start),
+             embeddedSize(rom_patch_016_bin_start, rom_patch_016_bin_end))
+    , dab_(asBytes(dab_firmware_bin_start),
+           embeddedSize(dab_firmware_bin_start, dab_firmware_bin_end))
+    , fm_(asBytes(fm_firmware_bin_start),
+          embeddedSize(fm_firmware_bin_start, fm_firmware_bin_end))
+{
+}
+
+const core::IFirmwareBlobReader& Si4684EmbeddedImages::romPatch() const noexcept
+{
+    return patch_;
+}
+
+const core::IFirmwareBlobReader& Si4684EmbeddedImages::dabFirmware() const noexcept
+{
+    return dab_;
+}
+
+const core::IFirmwareBlobReader& Si4684EmbeddedImages::fmFirmware() const noexcept
+{
+    return fm_;
+}
+
+const core::IFirmwareBlobReader& Si4684EmbeddedImages::applicationImage(
+    Si4684Band band) const noexcept
+{
+    switch (band) {
+    case Si4684Band::Dab:
+        return dab_;
+    case Si4684Band::Fm:
+        return fm_;
+    }
+    return dab_;
+}
+
+} // namespace si4684

Software/components/drivers/si4684/src/Si4684Tuner.cpp

@@ -0,0 +1,186 @@
+/**
+ * @file    Si4684Tuner.cpp
+ * @brief   Si4684Tuner implementation.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "si4684/Si4684Tuner.hpp"
+
+#include "si4684/Si4684Band.hpp"
+
+namespace si4684 {
+
+namespace {
+
+[[nodiscard]] core::FrequencyKHz defaultFmFrequency()
+{
+    return *core::FrequencyKHz::tryFromKhz(101500U);
+}
+
+} // namespace
+
+Si4684Tuner::Si4684Tuner(Si4684Driver& driver)
+    : driver_(driver)
+    , dabIndex_(0U)
+    , fmFrequency_(defaultFmFrequency())
+    , volume_(40U)
+{
+}
+
+core::TunerError Si4684Tuner::mapError(Si4684Error error) noexcept
+{
+    switch (error) {
+    case Si4684Error::NotBooted:
+        return core::TunerError::NotBooted;
+    case Si4684Error::WrongBand:
+        return core::TunerError::WrongBand;
+    case Si4684Error::TuneFailed:
+    case Si4684Error::StcTimeout:
+        return core::TunerError::TuneFailed;
+    default:
+        return core::TunerError::HardwareFailed;
+    }
+}
+
+std::expected<void, core::TunerError> Si4684Tuner::boot(core::TunerBand band)
+{
+    const Si4684Band hwBand =
+        (band == core::TunerBand::Fm) ? Si4684Band::Fm : Si4684Band::Dab;
+    if (auto result = driver_.boot(hwBand); !result) {
+        return std::unexpected(mapError(result.error()));
+    }
+    return {};
+}
+
+std::expected<core::TunerBand, core::TunerError> Si4684Tuner::currentBand() const
+{
+    if (!driver_.isBooted()) {
+        return std::unexpected(core::TunerError::NotBooted);
+    }
+    return driver_.loadedBand() == Si4684Band::Fm ? core::TunerBand::Fm
+                                                  : core::TunerBand::Dab;
+}
+
+std::expected<core::TunerStatus, core::TunerError> Si4684Tuner::readStatus()
+{
+    if (!driver_.isBooted()) {
+        return std::unexpected(core::TunerError::NotBooted);
+    }
+
+    core::TunerStatus status = {};
+    status.booted = true;
+    status.volume = volume_;
+    status.band = driver_.loadedBand() == Si4684Band::Fm ? core::TunerBand::Fm
+                                                         : core::TunerBand::Dab;
+
+    if (status.band == core::TunerBand::Dab) {
+        status.dabFreqIndex = dabIndex_;
+        if (auto dig = driver_.readDabDigRadStatus(); dig) {
+            status.locked = dig->valid;
+            status.dabFicQuality = dig->ficQuality;
+            status.dabCnrDb = dig->cnrDb;
+        } else {
+            return std::unexpected(mapError(dig.error()));
+        }
+    } else {
+        status.fmFrequency = fmFrequency_;
+        if (auto rsq = driver_.readFmRsq(); rsq) {
+            status.locked = rsq->valid;
+            status.fmFrequency = rsq->frequency;
+            status.fmRssiDbuV = rsq->rssiDbuV;
+            status.fmSnrDb = rsq->snrDb;
+            status.fmStereo = rsq->stereo;
+            fmFrequency_ = rsq->frequency;
+        } else {
+            return std::unexpected(mapError(rsq.error()));
+        }
+    }
+    return status;
+}
+
+std::expected<void, core::TunerError> Si4684Tuner::tuneDab(
+    std::uint8_t freqIndex)
+{
+    if (auto result = driver_.tuneDab(freqIndex); !result) {
+        return std::unexpected(mapError(result.error()));
+    }
+    dabIndex_ = freqIndex;
+    return {};
+}
+
+std::expected<void, core::TunerError> Si4684Tuner::tuneFm(
+    core::FrequencyKHz frequency)
+{
+    if (auto result = driver_.tuneFm(frequency); !result) {
+        return std::unexpected(mapError(result.error()));
+    }
+    fmFrequency_ = frequency;
+    return {};
+}
+
+std::expected<core::FrequencyKHz, core::TunerError> Si4684Tuner::seekFm(
+    core::SeekDirection direction)
+{
+    if (auto result = driver_.seekFm(direction, SeekBandWrap::Wrap); !result) {
+        return std::unexpected(mapError(result.error()));
+    }
+    fmFrequency_ = *result;
+    return *result;
+}
+
+std::expected<std::vector<core::TunerServiceEntry>, core::TunerError>
+Si4684Tuner::listDabServices()
+{
+    if (auto events = driver_.readDabEventStatus(); events) {
+        if (!events->serviceListReady) {
+            return std::unexpected(core::TunerError::ServiceListEmpty);
+        }
+    } else {
+        return std::unexpected(mapError(events.error()));
+    }
+
+    if (auto list = driver_.fetchDabServiceList(); list) {
+        std::vector<core::TunerServiceEntry> out;
+        out.reserve(list->size());
+        for (const auto& item : *list) {
+            core::TunerServiceEntry entry = {};
+            entry.serviceId = item.serviceId;
+            entry.componentId = item.componentId;
+            entry.label = item.label;
+            out.push_back(entry);
+        }
+        if (out.empty()) {
+            return std::unexpected(core::TunerError::ServiceListEmpty);
+        }
+        return out;
+    }
+    return std::unexpected(mapError(list.error()));
+}
+
+std::expected<void, core::TunerError> Si4684Tuner::playDabService(
+    std::uint32_t serviceId,
+    std::uint32_t componentId)
+{
+    if (auto result = driver_.startDabService(serviceId, componentId); !result) {
+        return std::unexpected(mapError(result.error()));
+    }
+    return {};
+}
+
+std::expected<void, core::TunerError> Si4684Tuner::setVolume(std::uint8_t level)
+{
+    if (auto result = driver_.setVolume(level); !result) {
+        return std::unexpected(mapError(result.error()));
+    }
+    volume_ = level & 0x3FU;
+    return {};
+}
+
+} // namespace si4684

Software/components/drivers/si4684/src/component_stub.cpp

@@ -1,33 +0,0 @@
-/**
- * @file    component_stub.cpp
- * @brief   Si4684 driver component placeholder (Slice 4).
- *
- * DigiRadio firmware — https://github.com/manvalan/DigiRadio
- *
- * Copyright 2026 Michele Bigi
- * SPDX-License-Identifier: Apache-2.0
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * @author  Michele Bigi
- * @date    2026-07-06
- */
-
-namespace si4684::detail {
-
-/**
- * @brief    si4684ComponentLinked — ensures the driver component links.
- *
- * @dname    si4684ComponentLinked
- * @return   n/a (type)
- * @pubstate n/a
- *
- * @author   Michele Bigi
- * @date     2026-07-06
- */
-void si4684ComponentLinked() noexcept {}
-
-} // namespace si4684::detail

Software/components/net/CMakeLists.txt

@@ -7,7 +7,7 @@ idf_component_register(
         "src/NetBootstrap.cpp"
     INCLUDE_DIRS "include"
     EMBED_FILES "www/index.html.gz"
-    REQUIRES core esp_wifi esp_netif esp_event nvs_flash esp_http_server
+    REQUIRES core esp_wifi esp_netif esp_event nvs_flash esp_http_server tuner
 )
 
 target_compile_features(${COMPONENT_LIB} PUBLIC cxx_std_23)

Software/components/net/include/net/NetBootstrap.hpp

@@ -27,6 +27,10 @@
 #include <expected>
 #include <optional>
 
+namespace tuner {
+class TunerService;
+} // namespace tuner
+
 namespace net {
 
 /**
@@ -47,6 +51,7 @@ public:
      *
      * @dname    start
      * @param    store  Secure store consulted for saved STA credentials.
+     * @param    tuner  Tuner service exposed by the HTTP API.
      * @return   NetBootstrap on success, or a NetError.
      * @pubstate none
      *
@@ -54,7 +59,7 @@ public:
      * @date     2026-07-06
      */
     [[nodiscard]] static std::expected<NetBootstrap, NetError>
-    start(core::ISecureStore& store);
+    start(core::ISecureStore& store, tuner::TunerService& tuner);
 
     NetBootstrap(const NetBootstrap&) = delete;
     NetBootstrap& operator=(const NetBootstrap&) = delete;

Software/components/net/include/net/SetupWebServer.hpp

@@ -23,10 +23,32 @@
 
 #include <expected>
 
+struct httpd_req;
+
+namespace tuner {
+class TunerService;
+} // namespace tuner
+
 struct httpd_handle;
 
 namespace net {
 
+/**
+ * @brief    HttpRouteContext — dependencies injected into HTTP handlers.
+ *
+ * @dname    HttpRouteContext
+ * @return   n/a (type)
+ * @pubstate Borrows store and tuner for the lifetime of SetupWebServer.
+ *           Passed as esp_http_server user_ctx (no file-scope globals).
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+struct HttpRouteContext {
+    core::ISecureStore* store;     ///< Secure store for Wi-Fi provisioning.
+    tuner::TunerService* tuner;    ///< Tuner service for tuner REST routes.
+};
+
 /**
  * @brief    SetupWebServer — setup UI, health, and Wi-Fi provisioning API.
  *
@@ -96,19 +118,23 @@ public:
      * @dname    start
      * @param    store     Secure store for POST /api/wifi persistence.
      * @param    netState  Active network phase exposed to handlers.
+     * @param    tuner     Tuner service for the tuner REST routes.
      * @return   Ok on success, or NetError::HttpServerStartFailed.
-     * @pubstate writes server_, store_, and netState_ on success.
+     * @pubstate writes server_, store_, netState_, and tuner_ on success.
      *
      * @author   Michele Bigi
      * @date     2026-07-06
      */
     [[nodiscard]] std::expected<void, NetError> start(core::ISecureStore& store,
-                                                      NetState netState);
+                                                      NetState netState,
+                                                      tuner::TunerService& tuner);
 
 private:
     httpd_handle* server_;
     core::ISecureStore* store_;
     NetState netState_;
+    tuner::TunerService* tuner_;
+    HttpRouteContext routeContext_;
 };
 
 } // namespace net

Software/components/net/src/NetBootstrap.cpp

@@ -23,6 +23,7 @@
 #include "esp_netif.h"
 #include "esp_wifi.h"
 #include "nvs_flash.h"
+#include "tuner/TunerService.hpp"
 
 namespace net {
 
@@ -97,7 +98,7 @@ constexpr char kTag[] = "NetBootstrap";
  * @date     2026-07-06
  */
 [[nodiscard]] std::expected<NetBootstrap, NetError>
-startSetupMode(core::ISecureStore& store)
+startSetupMode(core::ISecureStore& store, tuner::TunerService& tuner)
 {
     esp_netif_create_default_wifi_ap();
 
@@ -107,7 +108,7 @@ startSetupMode(core::ISecureStore& store)
     }
 
     SetupWebServer webServer;
-    if (auto webResult = webServer.start(store, NetState::SoftApSetup);
+    if (auto webResult = webServer.start(store, NetState::SoftApSetup, tuner);
         !webResult) {
         return std::unexpected(webResult.error());
     }
@@ -129,7 +130,7 @@ startSetupMode(core::ISecureStore& store)
  * @date     2026-07-06
  */
 [[nodiscard]] std::expected<NetBootstrap, NetError>
-startStaMode(core::ISecureStore& store)
+startStaMode(core::ISecureStore& store, tuner::TunerService& tuner)
 {
     auto credsResult = store.loadWifiCredentials();
     if (!credsResult) {
@@ -145,7 +146,7 @@ startStaMode(core::ISecureStore& store)
     }
 
     SetupWebServer webServer;
-    if (auto webResult = webServer.start(store, NetState::StaConnected);
+    if (auto webResult = webServer.start(store, NetState::StaConnected, tuner);
         !webResult) {
         return std::unexpected(webResult.error());
     }
@@ -158,7 +159,7 @@ startStaMode(core::ISecureStore& store)
 } // namespace
 
 std::expected<NetBootstrap, NetError>
-NetBootstrap::start(core::ISecureStore& store)
+NetBootstrap::start(core::ISecureStore& store, tuner::TunerService& tuner)
 {
     if (auto platform = initPlatform(); !platform) {
         return std::unexpected(platform.error());
@@ -169,14 +170,14 @@ NetBootstrap::start(core::ISecureStore& store)
     }
 
     if (store.hasWifiCredentials()) {
-        auto staResult = startStaMode(store);
+        auto staResult = startStaMode(store, tuner);
         if (staResult) {
             return staResult;
         }
         ESP_LOGW(kTag, "STA join failed — falling back to setup SoftAP");
     }
 
-    return startSetupMode(store);
+    return startSetupMode(store, tuner);
 }
 
 NetBootstrap::NetBootstrap(std::optional<SoftApHost> softAp,

Software/components/net/src/SetupWebServer.cpp

@@ -22,7 +22,10 @@
 #include "core/HealthStatus.hpp"
 #include "core/HealthStatusJson.hpp"
 #include "core/ParseError.hpp"
+#include "core/SeekDirection.hpp"
+#include "core/TunerJson.hpp"
 #include "core/WifiProvisionJson.hpp"
+#include "tuner/TunerService.hpp"
 
 #include "esp_http_server.h"
 #include "esp_log.h"
@@ -37,17 +40,30 @@ namespace net {
 
 namespace {
 constexpr char kTag[] = "SetupWebServer";
-constexpr char kFirmwareVersion[] = "0.2.0";
+constexpr char kFirmwareVersion[] = "0.4.0";
 constexpr unsigned kRebootDelaySec = 3;
 
-SetupWebServer* gActiveServer = nullptr;
-core::ISecureStore* gStore = nullptr;
-
 extern const uint8_t www_index_html_gz_start[] asm(
     "_binary_www_index_html_gz_start");
 extern const uint8_t www_index_html_gz_end[] asm(
     "_binary_www_index_html_gz_end");
 
+/**
+ * @brief    routeContextFrom — read handler dependencies from user_ctx.
+ *
+ * @dname    routeContextFrom
+ * @param    req  HTTP request handle from esp_http_server.
+ * @return   Route context pointer, or nullptr when unset.
+ * @pubstate none
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+[[nodiscard]] HttpRouteContext* routeContextFrom(httpd_req_t* req) noexcept
+{
+    return static_cast<HttpRouteContext*>(httpd_req_get_user_ctx(req));
+}
+
 /**
  * @brief    rebootTask — restart after provisioning so STA mode can run.
  *
@@ -91,6 +107,40 @@ void rebootTask(void* arg)
     return "parse_error";
 }
 
+[[nodiscard]] const char* tunerErrorToken(core::TunerError error) noexcept
+{
+    switch (error) {
+    case core::TunerError::NotBooted:
+        return "not_booted";
+    case core::TunerError::WrongBand:
+        return "wrong_band";
+    case core::TunerError::TuneFailed:
+        return "tune_failed";
+    case core::TunerError::ServiceListEmpty:
+        return "service_list_empty";
+    case core::TunerError::InvalidInput:
+        return "invalid_input";
+    case core::TunerError::HardwareFailed:
+        return "hardware_failed";
+    }
+    return "tuner_error";
+}
+
+[[nodiscard]] bool readRequestBody(httpd_req_t* req, std::array<char, 512>& body)
+{
+    int received = 0;
+    while (received < static_cast<int>(body.size()) - 1) {
+        const int chunk = httpd_req_recv(req, body.data() + received,
+                                         body.size() - 1 - received);
+        if (chunk <= 0) {
+            break;
+        }
+        received += chunk;
+    }
+    body[static_cast<std::size_t>(received)] = '\0';
+    return received > 0;
+}
+
 /**
  * @brief    healthGetHandler — serve GET /api/health as JSON.
  *
@@ -111,6 +161,208 @@ esp_err_t healthGetHandler(httpd_req_t* req)
     return httpd_resp_send(req, json.c_str(), json.size());
 }
 
+/**
+ * @brief    tunerStatusGetHandler — serve GET /api/tuner/status as JSON.
+ *
+ * @dname    tunerStatusGetHandler
+ * @param    req  HTTP request handle from esp_http_server.
+ * @return   ESP_OK on success, or an esp_err_t error code.
+ * @pubstate uses route context tuner service.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+esp_err_t tunerStatusGetHandler(httpd_req_t* req)
+{
+    auto* ctx = routeContextFrom(req);
+    if (ctx == nullptr || ctx->tuner == nullptr) {
+        httpd_resp_set_status(req, "503 Service Unavailable");
+        return httpd_resp_send(req, nullptr, 0);
+    }
+    auto status = ctx->tuner->refreshStatus();
+    if (!status) {
+        const std::string json =
+            core::serializeTunerErrorJson(tunerErrorToken(status.error()));
+        httpd_resp_set_status(req, "500 Internal Server Error");
+        httpd_resp_set_type(req, "application/json");
+        return httpd_resp_send(req, json.c_str(), json.size());
+    }
+    const std::string json = core::serializeTunerStatusJson(*status);
+    httpd_resp_set_type(req, "application/json");
+    return httpd_resp_send(req, json.c_str(), json.size());
+}
+
+/**
+ * @brief    tunerServicesGetHandler — serve GET /api/tuner/services as JSON.
+ *
+ * @dname    tunerServicesGetHandler
+ * @param    req  HTTP request handle from esp_http_server.
+ * @return   ESP_OK on success, or an esp_err_t error code.
+ * @pubstate uses route context tuner service.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+esp_err_t tunerServicesGetHandler(httpd_req_t* req)
+{
+    auto* ctx = routeContextFrom(req);
+    if (ctx == nullptr || ctx->tuner == nullptr) {
+        httpd_resp_set_status(req, "503 Service Unavailable");
+        return httpd_resp_send(req, nullptr, 0);
+    }
+    auto services = ctx->tuner->listDabServices();
+    if (!services) {
+        const std::string json =
+            core::serializeTunerErrorJson(tunerErrorToken(services.error()));
+        httpd_resp_set_status(req, "409 Conflict");
+        httpd_resp_set_type(req, "application/json");
+        return httpd_resp_send(req, json.c_str(), json.size());
+    }
+    const std::string json = core::serializeTunerServicesJson(*services);
+    httpd_resp_set_type(req, "application/json");
+    return httpd_resp_send(req, json.c_str(), json.size());
+}
+
+/**
+ * @brief    tunerTunePostHandler — accept POST /api/tuner/tune JSON.
+ *
+ * @dname    tunerTunePostHandler
+ * @param    req  HTTP request handle from esp_http_server.
+ * @return   ESP_OK on success, or an esp_err_t error code.
+ * @pubstate uses route context tuner service.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+esp_err_t tunerTunePostHandler(httpd_req_t* req)
+{
+    auto* ctx = routeContextFrom(req);
+    if (ctx == nullptr || ctx->tuner == nullptr) {
+        httpd_resp_set_status(req, "503 Service Unavailable");
+        return httpd_resp_send(req, nullptr, 0);
+    }
+
+    std::array<char, 512> body{};
+    if (!readRequestBody(req, body)) {
+        httpd_resp_set_status(req, "400 Bad Request");
+        return httpd_resp_send(req, nullptr, 0);
+    }
+
+    const auto parsed =
+        core::parseTunerTuneJson(std::string_view(body.data()));
+    if (!parsed) {
+        const std::string json = core::serializeTunerErrorJson("invalid_json");
+        httpd_resp_set_status(req, "400 Bad Request");
+        httpd_resp_set_type(req, "application/json");
+        return httpd_resp_send(req, json.c_str(), json.size());
+    }
+
+    std::expected<void, core::TunerError> result = std::unexpected(
+        core::TunerError::InvalidInput);
+    if (parsed->band == core::TunerBand::Dab) {
+        result = ctx->tuner->tuneDab(parsed->dabFreqIndex);
+    } else if (parsed->fmFrequency) {
+        result = ctx->tuner->tuneFm(*parsed->fmFrequency);
+    }
+
+    if (!result) {
+        const std::string json =
+            core::serializeTunerErrorJson(tunerErrorToken(result.error()));
+        httpd_resp_set_status(req, "409 Conflict");
+        httpd_resp_set_type(req, "application/json");
+        return httpd_resp_send(req, json.c_str(), json.size());
+    }
+
+    auto status = ctx->tuner->refreshStatus();
+    const std::string json = status
+        ? core::serializeTunerStatusJson(*status)
+        : std::string("{\"status\":\"ok\"}");
+    httpd_resp_set_type(req, "application/json");
+    return httpd_resp_send(req, json.c_str(), json.size());
+}
+
+/**
+ * @brief    tunerPlayPostHandler — accept POST /api/tuner/play JSON.
+ *
+ * @dname    tunerPlayPostHandler
+ * @param    req  HTTP request handle from esp_http_server.
+ * @return   ESP_OK on success, or an esp_err_t error code.
+ * @pubstate uses route context tuner service.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+esp_err_t tunerPlayPostHandler(httpd_req_t* req)
+{
+    auto* ctx = routeContextFrom(req);
+    if (ctx == nullptr || ctx->tuner == nullptr) {
+        httpd_resp_set_status(req, "503 Service Unavailable");
+        return httpd_resp_send(req, nullptr, 0);
+    }
+
+    std::array<char, 512> body{};
+    if (!readRequestBody(req, body)) {
+        httpd_resp_set_status(req, "400 Bad Request");
+        return httpd_resp_send(req, nullptr, 0);
+    }
+
+    const auto parsed =
+        core::parseTunerPlayJson(std::string_view(body.data()));
+    if (!parsed) {
+        const std::string json = core::serializeTunerErrorJson("invalid_json");
+        httpd_resp_set_status(req, "400 Bad Request");
+        httpd_resp_set_type(req, "application/json");
+        return httpd_resp_send(req, json.c_str(), json.size());
+    }
+
+    if (auto play = ctx->tuner->playDabService(parsed->serviceId,
+                                               parsed->componentId);
+        !play) {
+        const std::string json =
+            core::serializeTunerErrorJson(tunerErrorToken(play.error()));
+        httpd_resp_set_status(req, "409 Conflict");
+        httpd_resp_set_type(req, "application/json");
+        return httpd_resp_send(req, json.c_str(), json.size());
+    }
+
+    httpd_resp_set_type(req, "application/json");
+    return httpd_resp_send(req, "{\"status\":\"playing\"}", 20);
+}
+
+/**
+ * @brief    tunerSeekPostHandler — accept POST /api/tuner/seek (FM up).
+ *
+ * @dname    tunerSeekPostHandler
+ * @param    req  HTTP request handle from esp_http_server.
+ * @return   ESP_OK on success, or an esp_err_t error code.
+ * @pubstate uses route context tuner service with SeekDirection::Up.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+esp_err_t tunerSeekPostHandler(httpd_req_t* req)
+{
+    auto* ctx = routeContextFrom(req);
+    if (ctx == nullptr || ctx->tuner == nullptr) {
+        httpd_resp_set_status(req, "503 Service Unavailable");
+        return httpd_resp_send(req, nullptr, 0);
+    }
+
+    auto freq = ctx->tuner->seekFm(core::SeekDirection::Up);
+    if (freq) {
+        const std::string json = std::string("{\"frequency_khz\":")
+            + std::to_string(freq->value()) + "}";
+        httpd_resp_set_type(req, "application/json");
+        return httpd_resp_send(req, json.c_str(), json.size());
+    }
+
+    const std::string json =
+        core::serializeTunerErrorJson(tunerErrorToken(freq.error()));
+    httpd_resp_set_status(req, "409 Conflict");
+    httpd_resp_set_type(req, "application/json");
+    return httpd_resp_send(req, json.c_str(), json.size());
+}
+
 /**
  * @brief    indexGetHandler — serve gzipped setup page from flash.
  *
@@ -139,14 +391,15 @@ esp_err_t indexGetHandler(httpd_req_t* req)
  * @dname    wifiPostHandler
  * @param    req  HTTP request handle from esp_http_server.
  * @return   ESP_OK on success, or an esp_err_t error code.
- * @pubstate uses gActiveServer->store_ for persistence.
+ * @pubstate uses route context secure store for persistence.
  *
  * @author   Michele Bigi
  * @date     2026-07-06
  */
 esp_err_t wifiPostHandler(httpd_req_t* req)
 {
-    if (gStore == nullptr) {
+    auto* ctx = routeContextFrom(req);
+    if (ctx == nullptr || ctx->store == nullptr) {
         httpd_resp_set_status(req, "500 Internal Server Error");
         return httpd_resp_send(req, nullptr, 0);
     }
@@ -173,7 +426,7 @@ esp_err_t wifiPostHandler(httpd_req_t* req)
         return httpd_resp_send(req, json.c_str(), json.size());
     }
 
-    if (!gStore->saveWifiCredentials(parsed.value())) {
+    if (!ctx->store->saveWifiCredentials(parsed.value())) {
         const std::string json =
             core::serializeWifiProvisionErrorJson("store_failed");
         httpd_resp_set_status(req, "500 Internal Server Error");
@@ -196,6 +449,8 @@ SetupWebServer::SetupWebServer()
     : server_(nullptr)
     , store_(nullptr)
     , netState_(NetState::Uninitialized)
+    , tuner_(nullptr)
+    , routeContext_{nullptr, nullptr}
 {
 }
 
@@ -203,11 +458,14 @@ SetupWebServer::SetupWebServer(SetupWebServer&& other) noexcept
     : server_(other.server_)
     , store_(other.store_)
     , netState_(other.netState_)
+    , tuner_(other.tuner_)
+    , routeContext_(other.routeContext_)
 {
     other.server_ = nullptr;
     other.store_ = nullptr;
     other.netState_ = NetState::Uninitialized;
-    gActiveServer = this;
+    other.tuner_ = nullptr;
+    other.routeContext_ = {nullptr, nullptr};
 }
 
 SetupWebServer& SetupWebServer::operator=(SetupWebServer&& other) noexcept
@@ -219,30 +477,30 @@ SetupWebServer& SetupWebServer::operator=(SetupWebServer&& other) noexcept
         server_ = other.server_;
         store_ = other.store_;
         netState_ = other.netState_;
+        tuner_ = other.tuner_;
+        routeContext_ = other.routeContext_;
         other.server_ = nullptr;
         other.store_ = nullptr;
         other.netState_ = NetState::Uninitialized;
-        gActiveServer = this;
+        other.tuner_ = nullptr;
+        other.routeContext_ = {nullptr, nullptr};
     }
     return *this;
 }
 
 SetupWebServer::~SetupWebServer()
 {
-    if (gActiveServer == this) {
-        gActiveServer = nullptr;
-    }
-    if (gStore == store_) {
-        gStore = nullptr;
-    }
     if (server_ != nullptr) {
         httpd_stop(server_);
         server_ = nullptr;
     }
+    routeContext_ = {nullptr, nullptr};
 }
 
-std::expected<void, NetError> SetupWebServer::start(core::ISecureStore& store,
+std::expected<void, NetError> SetupWebServer::start(
-                                                    NetState netState)
+    core::ISecureStore& store,
+    NetState netState,
+    tuner::TunerService& tuner)
 {
     if (server_ != nullptr) {
         return {};
@@ -250,8 +508,9 @@ std::expected<void, NetError> SetupWebServer::start(core::ISecureStore& store,
 
     store_ = &store;
     netState_ = netState;
-    gActiveServer = this;
+    tuner_ = &tuner;
-    gStore = &store;
+    routeContext_.store = &store;
+    routeContext_.tuner = &tuner;
 
     httpd_config_t config = HTTPD_DEFAULT_CONFIG();
     config.server_port = 80;
@@ -259,16 +518,17 @@ std::expected<void, NetError> SetupWebServer::start(core::ISecureStore& store,
 
     if (httpd_start(&server_, &config) != ESP_OK) {
         ESP_LOGE(kTag, "httpd_start failed");
-        gActiveServer = nullptr;
+        routeContext_ = {nullptr, nullptr};
-        gStore = nullptr;
         return std::unexpected(NetError::HttpServerStartFailed);
     }
 
+    void* routeCtx = &routeContext_;
+
     const httpd_uri_t healthUri = {
         .uri = "/api/health",
         .method = HTTP_GET,
         .handler = healthGetHandler,
-        .user_ctx = nullptr,
+        .user_ctx = routeCtx,
     };
     httpd_register_uri_handler(server_, &healthUri);
 
@@ -276,7 +536,7 @@ std::expected<void, NetError> SetupWebServer::start(core::ISecureStore& store,
         .uri = "/",
         .method = HTTP_GET,
         .handler = indexGetHandler,
-        .user_ctx = nullptr,
+        .user_ctx = routeCtx,
     };
     httpd_register_uri_handler(server_, &indexUri);
 
@@ -284,10 +544,50 @@ std::expected<void, NetError> SetupWebServer::start(core::ISecureStore& store,
         .uri = "/api/wifi",
         .method = HTTP_POST,
         .handler = wifiPostHandler,
-        .user_ctx = nullptr,
+        .user_ctx = routeCtx,
     };
     httpd_register_uri_handler(server_, &wifiUri);
 
+    const httpd_uri_t tunerStatusUri = {
+        .uri = "/api/tuner/status",
+        .method = HTTP_GET,
+        .handler = tunerStatusGetHandler,
+        .user_ctx = routeCtx,
+    };
+    httpd_register_uri_handler(server_, &tunerStatusUri);
+
+    const httpd_uri_t tunerServicesUri = {
+        .uri = "/api/tuner/services",
+        .method = HTTP_GET,
+        .handler = tunerServicesGetHandler,
+        .user_ctx = routeCtx,
+    };
+    httpd_register_uri_handler(server_, &tunerServicesUri);
+
+    const httpd_uri_t tunerTuneUri = {
+        .uri = "/api/tuner/tune",
+        .method = HTTP_POST,
+        .handler = tunerTunePostHandler,
+        .user_ctx = routeCtx,
+    };
+    httpd_register_uri_handler(server_, &tunerTuneUri);
+
+    const httpd_uri_t tunerPlayUri = {
+        .uri = "/api/tuner/play",
+        .method = HTTP_POST,
+        .handler = tunerPlayPostHandler,
+        .user_ctx = routeCtx,
+    };
+    httpd_register_uri_handler(server_, &tunerPlayUri);
+
+    const httpd_uri_t tunerSeekUri = {
+        .uri = "/api/tuner/seek",
+        .method = HTTP_POST,
+        .handler = tunerSeekPostHandler,
+        .user_ctx = routeCtx,
+    };
+    httpd_register_uri_handler(server_, &tunerSeekUri);
+
     ESP_LOGI(kTag, "HTTP server listening on port 80");
     return {};
 }

Software/components/services/tuner/CMakeLists.txt

@@ -0,0 +1,8 @@
+idf_component_register(
+    SRCS
+        "src/TunerService.cpp"
+    INCLUDE_DIRS "include"
+    REQUIRES core
+)
+
+target_compile_features(${COMPONENT_LIB} PUBLIC cxx_std_23)

Software/components/services/tuner/include/tuner/TunerService.hpp

@@ -0,0 +1,173 @@
+/**
+ * @file    TunerService.hpp
+ * @brief   Application service orchestrating tuner operations for UI/API.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#include "core/FrequencyKHz.hpp"
+#include "core/ITuner.hpp"
+#include "core/SeekDirection.hpp"
+#include "core/TunerError.hpp"
+#include "core/TunerStatus.hpp"
+
+#include <cstdint>
+#include <expected>
+#include <vector>
+
+namespace tuner {
+
+/**
+ * @brief    TunerService — intent-level tuner API for HTTP and future UI.
+ *
+ * @dname    TunerService
+ * @return   n/a (type)
+ * @pubstate Borrows core::ITuner for the process lifetime. Tracks last tune
+ *           target and cached volume for status reporting. No public data
+ *           members.
+ *
+ * Delegates hardware to core::ITuner; maps driver failures to TunerError
+ * without exposing SPI details to the shell.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+class TunerService {
+public:
+    /**
+     * @brief    TunerService — bind to a tuner driver for the process lifetime.
+     *
+     * @dname    TunerService
+     * @param    tuner  Driver implementation (must outlive this service).
+     * @pubstate stores tuner reference; initialises last tune defaults.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    explicit TunerService(core::ITuner& tuner);
+
+    /**
+     * @brief    refreshStatus — read a fresh tuner snapshot from the driver.
+     *
+     * @dname    refreshStatus
+     * @return   TunerStatus on success, or a TunerError from ITuner.
+     * @pubstate reads tuner_; updates cached volume_ on success.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<core::TunerStatus, core::TunerError>
+    refreshStatus();
+
+    /**
+     * @brief    tuneDab — tune to a Band III ensemble index.
+     *
+     * @dname    tuneDab
+     * @param    freqIndex  Ensemble index 0–37.
+     * @return   Ok on success, or a TunerError from ITuner.
+     * @pubstate writes lastDabIndex_ on success.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, core::TunerError> tuneDab(
+        std::uint8_t freqIndex);
+
+    /**
+     * @brief    tuneFm — tune to an FM centre frequency.
+     *
+     * @dname    tuneFm
+     * @param    frequency  Validated FM centre frequency.
+     * @return   Ok on success, or a TunerError from ITuner.
+     * @pubstate writes lastFmFrequency_ on success.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, core::TunerError> tuneFm(
+        core::FrequencyKHz frequency);
+
+    /**
+     * @brief    seekFm — seek FM in the given direction.
+     *
+     * @dname    seekFm
+     * @param    direction  Up or Down scan direction.
+     * @return   New centre frequency, or a TunerError.
+     * @pubstate writes lastFmFrequency_ on success.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<core::FrequencyKHz, core::TunerError> seekFm(
+        core::SeekDirection direction);
+
+    /**
+     * @brief    listDabServices — programmes available on the current ensemble.
+     *
+     * @dname    listDabServices
+     * @return   Service entries, or a TunerError from ITuner.
+     * @pubstate reads tuner_.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<std::vector<core::TunerServiceEntry>,
+                                core::TunerError>
+    listDabServices();
+
+    /**
+     * @brief    playDabService — start playback of a DAB programme.
+     *
+     * @dname    playDabService
+     * @param    serviceId    Selected service identifier.
+     * @param    componentId  Audio component within the service.
+     * @return   Ok on success, or a TunerError from ITuner.
+     * @pubstate delegates to tuner_.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, core::TunerError> playDabService(
+        std::uint32_t serviceId, std::uint32_t componentId);
+
+    /**
+     * @brief    setVolume — set tuner output attenuation.
+     *
+     * @dname    setVolume
+     * @param    level  Attenuator 0–63.
+     * @return   Ok on success, or a TunerError from ITuner.
+     * @pubstate writes volume_ on success.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] std::expected<void, core::TunerError> setVolume(
+        std::uint8_t level);
+
+    /**
+     * @brief    tuner — borrow the underlying driver for diagnostics.
+     *
+     * @dname    tuner
+     * @return   Reference to the injected ITuner implementation.
+     * @pubstate reads tuner_.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] core::ITuner& tuner() noexcept;
+
+private:
+    core::ITuner& tuner_;
+    std::uint8_t lastDabIndex_;
+    core::FrequencyKHz lastFmFrequency_;
+    std::uint8_t volume_;
+};
+
+} // namespace tuner

Software/components/services/tuner/src/TunerService.cpp

@@ -0,0 +1,101 @@
+/**
+ * @file    TunerService.cpp
+ * @brief   TunerService implementation.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "tuner/TunerService.hpp"
+
+namespace tuner {
+
+namespace {
+
+[[nodiscard]] core::FrequencyKHz defaultFmFrequency()
+{
+    return *core::FrequencyKHz::tryFromKhz(101500U);
+}
+
+} // namespace
+
+TunerService::TunerService(core::ITuner& tuner)
+    : tuner_(tuner)
+    , lastDabIndex_(0U)
+    , lastFmFrequency_(defaultFmFrequency())
+    , volume_(40U)
+{
+}
+
+std::expected<core::TunerStatus, core::TunerError> TunerService::refreshStatus()
+{
+    auto status = tuner_.readStatus();
+    if (status) {
+        volume_ = status->volume;
+    }
+    return status;
+}
+
+std::expected<void, core::TunerError> TunerService::tuneDab(
+    std::uint8_t freqIndex)
+{
+    if (auto result = tuner_.tuneDab(freqIndex); !result) {
+        return result;
+    }
+    lastDabIndex_ = freqIndex;
+    return {};
+}
+
+std::expected<void, core::TunerError> TunerService::tuneFm(
+    core::FrequencyKHz frequency)
+{
+    if (auto result = tuner_.tuneFm(frequency); !result) {
+        return result;
+    }
+    lastFmFrequency_ = frequency;
+    return {};
+}
+
+std::expected<core::FrequencyKHz, core::TunerError> TunerService::seekFm(
+    core::SeekDirection direction)
+{
+    auto result = tuner_.seekFm(direction);
+    if (result) {
+        lastFmFrequency_ = *result;
+    }
+    return result;
+}
+
+std::expected<std::vector<core::TunerServiceEntry>, core::TunerError>
+TunerService::listDabServices()
+{
+    return tuner_.listDabServices();
+}
+
+std::expected<void, core::TunerError> TunerService::playDabService(
+    std::uint32_t serviceId,
+    std::uint32_t componentId)
+{
+    return tuner_.playDabService(serviceId, componentId);
+}
+
+std::expected<void, core::TunerError> TunerService::setVolume(std::uint8_t level)
+{
+    if (auto result = tuner_.setVolume(level); !result) {
+        return result;
+    }
+    volume_ = level & 0x3FU;
+    return {};
+}
+
+core::ITuner& TunerService::tuner() noexcept
+{
+    return tuner_;
+}
+
+} // namespace tuner

Software/instructions.md

@@ -46,11 +46,12 @@ Repository: https://github.com/manvalan/DigiRadio
 
 1. **Walking skeleton** — done (Slice 1).
 2. **Secure store + Wi-Fi provisioning** — done (Slice 2).
-3. Station/frequency list model + persistence + UI.
+3. **Companion-chip boot** — done (Slice 3): Si4684 DAB + ADAU1701 RAM load.
-4. Si4684 driver: power-up, load image, tune, read RSQ.
+4. Station/frequency list model + persistence + UI.
-5. ADAU1701 driver: RAM boot, then safeload EQ + input mixer.
+5. Si4684 tuning: RSQ, station list, DAB properties.
-6. FSC-BT1035 driver: AT init (incl. `AT+AUXCFG=1`), audio out.
+6. ADAU1701 runtime: safeload EQ + input mixer.
-7. Integration: TunerService + AudioService end to end.
+7. FSC-BT1035 driver: AT init (incl. `AT+AUXCFG=1`), audio out.
+8. Integration: TunerService + AudioService end to end.
 
 ## Slice 1 — Walking skeleton (complete)
 
@@ -69,7 +70,7 @@ Behaviour:
 - Bring up SoftAP with a known SSID (e.g. `DigiRadio-setup`).
 - Start an HTTP server serving one minimal gzipped page from flash.
 - Expose `GET /api/health` returning a typed DTO serialised by the pure
-  core, e.g. `{"status":"ok","fw":"0.2.0"}`.
+  core, e.g. `{"status":"ok","fw":"0.3.0"}`.
 
 Documentation (required):
 - Doxygen doc blocks on every class/method; `doxygen Doxyfile` green.
@@ -96,3 +97,25 @@ Acceptance criteria:
 
 Out of scope: station list, user credentials, NVS encryption enablement
 (production), chip drivers.
+
+## Slice 3 — Companion-chip boot (complete)
+
+Goal: load Si4684 DAB firmware and ADAU1701 SigmaStudio program from
+`Firmware/` on every boot, before network bring-up.
+
+Build:
+- `Firmware/Si4684-Firmware/` — `rom_patch_016.bin`, `dab_firmware.bin`,
+  `fm_firmware.bin` (FM via `tools/fetch_si4684_firmware.py --si46xx-dir`).
+- `Firmware/ADAU1701-Firmware/` — SigmaStudio export (`DigiRadio_IC_1.h`, …).
+- `core::IFirmwareBlobReader` + `EmbeddedBlobReader` for chunked HOST_LOAD.
+- `si4684::Si4684Driver`, `adau1701::Adau1701Driver`, `HardwareBootstrap`.
+
+Behaviour:
+- `app_main` calls `HardwareBootstrap::boot()` first (Si4684, then ADAU1701).
+- On failure, firmware logs and halts before Wi-Fi.
+
+Acceptance criteria:
+- [x] AN649 boot sequence with streaming blobs (no full image on heap).
+- [x] ADAU1701 reset + I2C + `default_download_IC_1()` replay.
+- [x] Host test for `EmbeddedBlobReader`; manual sync green.
+- [ ] Device flash verified (requires ESP-IDF toolchain on build host).

Software/main/CMakeLists.txt

@@ -1,5 +1,7 @@
 idf_component_register(
-    SRCS "main.cpp"
+    SRCS
+        "main.cpp"
+        "hardware_bootstrap.cpp"
     INCLUDE_DIRS "."
-    REQUIRES core net secure_store
+    REQUIRES core net secure_store adau1701 si4684 tuner
 )

Software/main/hardware_bootstrap.cpp

@@ -0,0 +1,87 @@
+/**
+ * @file    hardware_bootstrap.cpp
+ * @brief   HardwareBootstrap implementation.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+
+#include "hardware_bootstrap.hpp"
+
+#include "adau1701/Adau1701Driver.hpp"
+#include "board_pins.hpp"
+#include "si4684/Si4684Band.hpp"
+#include "si4684/Si4684Driver.hpp"
+#include "si4684/Si4684EmbeddedImages.hpp"
+#include "si4684/Si4684Tuner.hpp"
+
+#include "driver/spi_master.h"
+#include "esp_log.h"
+
+namespace hardware {
+
+namespace {
+constexpr char kTag[] = "hw_boot";
+
+si4684::Si4684EmbeddedImages gImages;
+si4684::Si4684Driver gSi4684(
+    si4684::Si4684Pins{
+        .spiHost = SPI2_HOST,
+        .csGpio = board::pins::Si4684Cs,
+        .misoGpio = board::pins::Si4684Miso,
+        .mosiGpio = board::pins::Si4684Mosi,
+        .sclkGpio = board::pins::Si4684Sclk,
+        .rstbGpio = board::pins::Si4684Rstb,
+        .intbGpio = board::pins::Si4684Intb,
+    },
+    gImages.romPatch(),
+    gImages.dabFirmware(),
+    gImages.fmFirmware());
+si4684::Si4684Tuner gSi4684Tuner(gSi4684);
+
+adau1701::Adau1701Driver gAdau1701(
+    adau1701::Adau1701Pins{
+        .i2cSda = board::pins::Adau1701Sda,
+        .i2cScl = board::pins::Adau1701Scl,
+        .resetGpio = board::pins::Adau1701Reset,
+        .i2cAddr7 = board::pins::Adau1701Addr,
+    });
+
+bool gReady = false;
+} // namespace
+
+std::expected<void, HardwareBootError> HardwareBootstrap::boot()
+{
+    if (gReady) {
+        return {};
+    }
+
+    if (auto tunerResult = gSi4684.boot(si4684::Si4684Band::Dab); !tunerResult) {
+        ESP_LOGE(kTag, "Si4684 boot failed");
+        return std::unexpected(HardwareBootError::Si4684BootFailed);
+    }
+
+    if (!gAdau1701.isBooted()) {
+        auto dspResult = gAdau1701.boot();
+        if (!dspResult) {
+            ESP_LOGE(kTag, "ADAU1701 boot failed");
+            return std::unexpected(HardwareBootError::Adau1701BootFailed);
+        }
+    }
+
+    gReady = true;
+    ESP_LOGI(kTag, "companion chips ready");
+    return {};
+}
+
+si4684::Si4684Tuner& HardwareBootstrap::si4684Tuner()
+{
+    return gSi4684Tuner;
+}
+
+} // namespace hardware

Software/main/hardware_bootstrap.hpp

@@ -0,0 +1,80 @@
+/**
+ * @file    hardware_bootstrap.hpp
+ * @brief   Boot Si4684 and ADAU1701 companion chips at application start.
+ *
+ * DigiRadio firmware — https://github.com/manvalan/DigiRadio
+ *
+ * Copyright 2026 Michele Bigi
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * @author  Michele Bigi
+ * @date    2026-07-06
+ */
+#pragma once
+
+#include <expected>
+
+namespace si4684 {
+class Si4684Tuner;
+} // namespace si4684
+
+namespace hardware {
+
+/**
+ * @brief    HardwareBootError — companion-chip boot failure causes.
+ *
+ * @dname    HardwareBootError
+ * @return   n/a (type)
+ * @pubstate n/a
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+enum class HardwareBootError {
+    Si4684BootFailed,
+    Adau1701BootFailed,
+};
+
+/**
+ * @brief    HardwareBootstrap — orchestrates Si4684 then ADAU1701 bring-up.
+ *
+ * @dname    HardwareBootstrap
+ * @return   n/a (type)
+ * @pubstate Owns static driver instances for the process lifetime. Must be
+ *           called once from app_main before network start.
+ *
+ * @author   Michele Bigi
+ * @date     2026-07-06
+ */
+class HardwareBootstrap {
+public:
+    /**
+     * @brief    boot — load Si4684 DAB image then replay ADAU1701 program.
+     *
+     * @dname    boot
+     * @return   Ok on success, or HardwareBootError.
+     * @pubstate constructs static Si4684 and ADAU1701 drivers on first call.
+     *
+     * Fail-closed: callers must not start Wi-Fi when this returns an error.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] static std::expected<void, HardwareBootError> boot();
+
+    /**
+     * @brief    si4684Tuner — borrow the Si4684 ITuner adapter after boot.
+     *
+     * @dname    si4684Tuner
+     * @return   Reference to the static Si4684Tuner instance.
+     * @pubstate reads static storage initialised by boot().
+     *
+     * Valid only after a successful boot() call in the same process.
+     *
+     * @author   Michele Bigi
+     * @date     2026-07-06
+     */
+    [[nodiscard]] static si4684::Si4684Tuner& si4684Tuner();
+};
+
+} // namespace hardware

Software/main/main.cpp

@@ -7,17 +7,14 @@
  * Copyright 2026 Michele Bigi
  * SPDX-License-Identifier: Apache-2.0
  *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
  * @author  Michele Bigi
  * @date    2026-07-06
  */
 
+#include "hardware_bootstrap.hpp"
 #include "net/NetBootstrap.hpp"
 #include "secure_store/NvsSecureStore.hpp"
+#include "tuner/TunerService.hpp"
 
 #include "esp_log.h"
 #include "freertos/FreeRTOS.h"
@@ -28,16 +25,6 @@ namespace {
 constexpr char kTag[] = "digiradio";
 constexpr TickType_t kHeartbeatPeriod = pdMS_TO_TICKS(5000);
 
-/**
- * @brief    heartbeatTask — periodic alive log for bring-up verification.
- *
- * @dname    heartbeatTask
- * @param    arg  Unused task parameter.
- * @pubstate none
- *
- * @author   Michele Bigi
- * @date     2026-07-06
- */
 void heartbeatTask(void* arg)
 {
     (void)arg;
@@ -50,24 +37,30 @@ void heartbeatTask(void* arg)
 } // namespace
 
 /**
- * @brief    app_main — ESP-IDF application entry point.
+ * @brief    app_main — ESP-IDF entry point for DigiRadio firmware.
  *
  * @dname    app_main
- * @pubstate starts NvsSecureStore, NetBootstrap, and the heartbeat task.
+ * @pubstate boots companion chips, network stack, and heartbeat task.
- *
- * Slice 2: joins a stored Wi-Fi network when credentials exist, otherwise
- * opens the DigiRadio-setup SoftAP for provisioning via the web UI.
  *
  * @author   Michele Bigi
  * @date     2026-07-06
  */
 extern "C" void app_main()
 {
-    ESP_LOGI(kTag, "DigiRadio firmware boot — Slice 2");
+    ESP_LOGI(kTag, "DigiRadio firmware boot — Slice 4");
+
+    auto hwResult = hardware::HardwareBootstrap::boot();
+    if (!hwResult) {
+        ESP_LOGE(kTag, "companion chip boot failed — halting");
+        return;
+    }
+
+    static tuner::TunerService tunerService(
+        hardware::HardwareBootstrap::si4684Tuner());
 
     static secure_store::NvsSecureStore store;
 
-    auto netResult = net::NetBootstrap::start(store);
+    auto netResult = net::NetBootstrap::start(store, tunerService);
     if (!netResult) {
         ESP_LOGE(kTag, "network bootstrap failed");
         return;

Software/tools/extract_si4684_blob.py

@@ -0,0 +1,88 @@
+#!/usr/bin/env python3
+"""extract_si4684_blob.py — convert Si4684 C arrays or copies to .bin files.
+
+DigiRadio firmware — https://github.com/manvalan/DigiRadio
+
+Copyright 2026 Michele Bigi
+SPDX-License-Identifier: Apache-2.0
+
+Usage:
+    # From a SigmaStudio-style C header (PE5PVB firmware.h, Si468xROM.h):
+    tools/extract_si4684_blob.py --header src/firmware.h --array firmware \\
+        --out Firmware/Si4684-Firmware/dab_firmware.bin
+
+    # Copy an existing Skyworks .bin from an eval-board folder:
+    tools/extract_si4684_blob.py --copy ~/si46xx_firmware/fm_radio_5_1_0.bin \\
+        --out Firmware/Si4684-Firmware/fm_firmware.bin
+"""
+
+from __future__ import annotations
+
+import argparse
+import re
+import shutil
+import sys
+from pathlib import Path
+
+
+def extract_c_array(header: Path, array_name: str) -> bytes:
+    text = header.read_text(encoding="utf-8", errors="replace")
+    pattern = rf"{re.escape(array_name)}\s*\[\s*\]\s*=\s*\{{(.*?)\}};"
+    match = re.search(pattern, text, re.S)
+    if not match:
+        raise SystemExit(f"array {array_name!r} not found in {header}")
+    values = re.findall(r"0x[0-9a-fA-F]+", match.group(1))
+    if not values:
+        raise SystemExit(f"array {array_name!r} is empty in {header}")
+    return bytes(int(v, 16) for v in values)
+
+
+def extract_flash_region(dump: Path, offset: int, size: int) -> bytes:
+    data = dump.read_bytes()
+    end = offset + size
+    if end > len(data):
+        raise SystemExit(
+            f"flash dump too small: need {end} bytes, have {len(data)}"
+        )
+    return data[offset:end]
+
+
+def main() -> int:
+    ap = argparse.ArgumentParser(description=__doc__)
+    ap.add_argument("--out", type=Path, required=True, help="output .bin path")
+    src = ap.add_mutually_exclusive_group(required=True)
+    src.add_argument("--header", type=Path, help="C header with byte array")
+    src.add_argument("--copy", type=Path, help="existing firmware .bin to copy")
+    src.add_argument("--flash-dump", type=Path, help="full SPI flash dump")
+    ap.add_argument("--array", help="array name when using --header")
+    ap.add_argument(
+        "--offset",
+        type=lambda s: int(s, 0),
+        default=0x106000,
+        help="byte offset for --flash-dump (default: FM region from dirb.tech)",
+    )
+    ap.add_argument(
+        "--size",
+        type=lambda s: int(s, 0),
+        default=0x81721,
+        help="byte length for --flash-dump (default: FM V5.1.0 size)",
+    )
+    args = ap.parse_args()
+
+    if args.header is not None:
+        if not args.array:
+            ap.error("--array is required with --header")
+        payload = extract_c_array(args.header, args.array)
+    elif args.copy is not None:
+        payload = args.copy.read_bytes()
+    else:
+        payload = extract_flash_region(args.flash_dump, args.offset, args.size)
+
+    args.out.parent.mkdir(parents=True, exist_ok=True)
+    args.out.write_bytes(payload)
+    print(f"wrote {args.out} ({len(payload)} bytes)")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())

Software/tools/extract_ugreen_radio_cli.py

@@ -0,0 +1,322 @@
+#!/usr/bin/env python3
+"""extract_ugreen_radio_cli.py — pull Si468x blobs from uGreen radio_cli ELF.
+
+DigiRadio firmware — https://github.com/manvalan/DigiRadio
+
+Copyright 2026 Michele Bigi
+SPDX-License-Identifier: Apache-2.0
+
+uGreen embeds Skyworks firmware inside ``radio_cli`` (Files_v16.zip). This module
+locates ``fw_*`` rodata symbols and writes raw ``.bin`` payloads for DigiRadio
+HOST_LOAD boot (AN649 / PE5PVB flow).
+
+Obtain Files_v16.zip from https://ugreen.eu/downloads/ (DABBoard customer pack).
+Do not redistribute extracted blobs in public repositories.
+"""
+
+from __future__ import annotations
+
+import argparse
+import struct
+import subprocess
+import sys
+import zipfile
+from dataclasses import dataclass
+from pathlib import Path
+
+# Exact HOST_LOAD sizes observed in radio_cli power_up_and_load (ARM64 builds).
+UGREEN_KNOWN_SIZES: dict[str, int] = {
+    "fw_rom00_patch016bin": 5796,
+    "fw_dab_radio_5_0_5bin": 521_448,
+    "fw_dab_radio_6_0_6bin": 496_944,
+    "fw_fmhd_radio_5_0_4bin": 530_184,
+    "fw_fmhd_radio_5_1_3bin": 531_300,
+}
+
+FM_SYMBOL_PRIORITY = (
+    "fw_fmhd_radio_5_1_3bin",
+    "fw_fmhd_radio_5_1_0bin",
+    "fw_fm_radio_5_1_0bin",
+    "fw_fmhd_radio_5_0_4bin",
+    "fw_fm_radio_5_0_9bin",
+)
+
+DAB_SYMBOL_PRIORITY = (
+    "fw_dab_radio_6_0_6bin",
+    "fw_dab_radio_5_0_8bin",
+    "fw_dab_radio_5_0_5bin",
+    "fw_dab_radio_4_0_5bif",
+)
+
+PATCH_SYMBOL = "fw_rom00_patch016bin"
+
+RADIO_CLI_GLOB = ("radio_cli_v*", "radio_cli")
+
+
+@dataclass(frozen=True)
+class FirmwareBlob:
+    symbol: str
+    offset: int
+    size: int
+    data: bytes
+
+
+def resolve_radio_cli(path: Path) -> Path:
+    """Return path to radio_cli ELF inside a file, zip, or directory."""
+    path = path.expanduser().resolve()
+    if path.is_file() and zipfile.is_zipfile(path):
+        with zipfile.ZipFile(path) as zf:
+            names = [
+                n
+                for n in zf.namelist()
+                if "radio_cli" in Path(n).name and not n.endswith("/")
+            ]
+            if not names:
+                raise SystemExit(f"No radio_cli binary found inside {path}")
+            # Prefer 64-bit builds (same blobs, easier to test on desktop nm).
+            names.sort(key=lambda n: ("64-bit" not in n, n))
+            chosen = names[0]
+            tmp_dir = Path(path.parent, f".ugreen-extract-{path.stem}")
+            tmp_dir.mkdir(exist_ok=True)
+            out = tmp_dir / Path(chosen).name
+            if not out.exists() or out.stat().st_mtime < path.stat().st_mtime:
+                out.write_bytes(zf.read(chosen))
+            return out
+
+    if path.is_dir():
+        for pattern in ("**/bin/64-bit/radio_cli*", "**/bin/32-bit/radio_cli*"):
+            matches = sorted(path.glob(pattern))
+            if matches:
+                return matches[0]
+        for pattern in RADIO_CLI_GLOB:
+            matches = sorted(path.rglob(pattern))
+            if matches:
+                return matches[0]
+        raise SystemExit(f"No radio_cli binary under {path}")
+
+    if path.is_file():
+        return path
+
+    raise SystemExit(f"Path not found: {path}")
+
+
+def _run_nm(elf: Path) -> str:
+    for cmd in (["llvm-nm", str(elf)], ["nm", str(elf)]):
+        try:
+            proc = subprocess.run(
+                cmd, capture_output=True, text=True, check=False
+            )
+        except FileNotFoundError:
+            continue
+        if proc.returncode == 0 and proc.stdout.strip():
+            return proc.stdout
+    raise SystemExit(
+        f"Could not read symbols from {elf} (install nm or llvm-nm)"
+    )
+
+
+def _parse_nm_output(text: str) -> dict[str, int]:
+    symbols: dict[str, int] = {}
+    for line in text.splitlines():
+        parts = line.split()
+        if len(parts) < 3:
+            continue
+        addr_s, sym_type, name = parts[0], parts[1], parts[2]
+        if sym_type not in {"R", "D", "r"}:
+            continue
+        if not name.startswith("fw_"):
+            continue
+        try:
+            symbols[name] = int(addr_s, 16)
+        except ValueError:
+            continue
+    return symbols
+
+
+def _elf_vma_to_file_offset(elf: Path, vma: int) -> int:
+    data = elf.read_bytes()
+    if data[:4] != b"\x7fELF":
+        raise SystemExit(f"Not an ELF file: {elf}")
+
+    ei_class = data[4]
+    if ei_class == 1:
+        e_shoff = struct.unpack_from("<I", data, 0x20)[0]
+        e_shentsize = struct.unpack_from("<H", data, 0x2E)[0]
+        e_shnum = struct.unpack_from("<H", data, 0x30)[0]
+        e_shstrndx = struct.unpack_from("<H", data, 0x32)[0]
+        sh_fmt = "<IIIIIIII"
+    elif ei_class == 2:
+        e_shoff = struct.unpack_from("<Q", data, 0x28)[0]
+        e_shentsize = struct.unpack_from("<H", data, 0x3A)[0]
+        e_shnum = struct.unpack_from("<H", data, 0x3C)[0]
+        e_shstrndx = struct.unpack_from("<H", data, 0x3E)[0]
+        sh_fmt = "<IIQQQQIIQQ"
+    else:
+        raise SystemExit(f"Unsupported ELF class in {elf}")
+
+    if e_shnum == 0:
+        return vma
+
+    def read_section(index: int) -> tuple[int, int, int]:
+        off = e_shoff + index * e_shentsize
+        fields = struct.unpack_from(sh_fmt, data, off)
+        if ei_class == 1:
+            sh_name, sh_type, sh_flags, sh_addr, sh_offset, sh_size = fields[:6]
+        else:
+            sh_name, sh_type, sh_flags, sh_addr, sh_offset, sh_size = fields[:6]
+        return sh_addr, sh_offset, sh_size
+
+    shstr_off = read_section(e_shstrndx)[1]
+
+    for index in range(e_shnum):
+        sh_addr, sh_offset, sh_size = read_section(index)
+        if sh_size == 0:
+            continue
+        if sh_addr <= vma < sh_addr + sh_size:
+            return sh_offset + (vma - sh_addr)
+
+    return vma
+
+
+def _pick_symbol(symbols: dict[str, int], priority: tuple[str, ...]) -> str | None:
+    for name in priority:
+        if name in symbols:
+            return name
+    return None
+
+
+def _blob_size(
+    symbol: str,
+    vma: int,
+    ordered: list[tuple[str, int]],
+    file_size: int,
+    file_offset: int,
+) -> int:
+    if symbol in UGREEN_KNOWN_SIZES:
+        return UGREEN_KNOWN_SIZES[symbol]
+
+    for name, addr in ordered:
+        if addr > vma:
+            return addr - vma
+
+    return file_size - file_offset
+
+
+def extract_blob(elf: Path, symbol: str, symbols: dict[str, int]) -> FirmwareBlob:
+    if symbol not in symbols:
+        raise SystemExit(f"Symbol {symbol!r} not found in {elf}")
+
+    vma = symbols[symbol]
+    file_offset = _elf_vma_to_file_offset(elf, vma)
+    ordered = sorted(symbols.items(), key=lambda item: item[1])
+    size = _blob_size(
+        symbol, vma, ordered, elf.stat().st_size, file_offset
+    )
+
+    data = elf.read_bytes()
+    end = file_offset + size
+    if end > len(data):
+        raise SystemExit(
+            f"{symbol}: need {size} bytes at file offset 0x{file_offset:x}, "
+            f"ELF size is {len(data)}"
+        )
+
+    payload = data[file_offset:end]
+    if len(payload) != size:
+        raise SystemExit(f"{symbol}: short read ({len(payload)} != {size})")
+
+    return FirmwareBlob(symbol, file_offset, size, payload)
+
+
+def extract_images(
+    source: Path,
+    *,
+    want_fm: bool = True,
+    want_dab: bool = False,
+    want_patch: bool = False,
+) -> dict[str, FirmwareBlob]:
+    elf = resolve_radio_cli(source)
+    symbols = _parse_nm_output(_run_nm(elf))
+    if not symbols:
+        raise SystemExit(f"No fw_* symbols in {elf}")
+
+    out: dict[str, FirmwareBlob] = {}
+
+    if want_patch:
+        out["patch"] = extract_blob(elf, PATCH_SYMBOL, symbols)
+
+    if want_dab:
+        dab_sym = _pick_symbol(symbols, DAB_SYMBOL_PRIORITY)
+        if dab_sym is None:
+            raise SystemExit(f"No DAB fw_* symbol in {elf}")
+        out["dab"] = extract_blob(elf, dab_sym, symbols)
+
+    if want_fm:
+        fm_sym = _pick_symbol(symbols, FM_SYMBOL_PRIORITY)
+        if fm_sym is None:
+            raise SystemExit(f"No FM fw_* symbol in {elf}")
+        out["fm"] = extract_blob(elf, fm_sym, symbols)
+
+    return out
+
+
+def write_blobs(blobs: dict[str, FirmwareBlob], out_dir: Path) -> None:
+    mapping = {
+        "patch": "rom_patch_016.bin",
+        "dab": "dab_firmware.bin",
+        "fm": "fm_firmware.bin",
+    }
+    out_dir.mkdir(parents=True, exist_ok=True)
+    for key, blob in blobs.items():
+        dest = out_dir / mapping[key]
+        dest.write_bytes(blob.data)
+        print(
+            f"wrote {dest} ({len(blob.data)} bytes) "
+            f"from {blob.symbol} @ 0x{blob.offset:x}"
+        )
+
+
+def main() -> int:
+    ap = argparse.ArgumentParser(description=__doc__)
+    ap.add_argument(
+        "source",
+        type=Path,
+        help="radio_cli ELF, Files_v16.zip, or unpacked Files_v16 directory",
+    )
+    ap.add_argument(
+        "--out-dir",
+        type=Path,
+        default=Path(__file__).resolve().parents[1] / "Firmware" / "Si4684-Firmware",
+        help="output directory for .bin files",
+    )
+    ap.add_argument("--fm", action="store_true", help="extract FM image")
+    ap.add_argument("--dab", action="store_true", help="extract DAB image")
+    ap.add_argument("--patch", action="store_true", help="extract ROM patch")
+    ap.add_argument(
+        "--all",
+        action="store_true",
+        help="extract patch, DAB, and FM",
+    )
+    args = ap.parse_args()
+
+    if args.all:
+        want_fm = want_dab = want_patch = True
+    else:
+        want_fm = args.fm
+        want_dab = args.dab
+        want_patch = args.patch
+        if not (want_fm or want_dab or want_patch):
+            want_fm = True
+
+    blobs = extract_images(
+        args.source,
+        want_fm=want_fm,
+        want_dab=want_dab,
+        want_patch=want_patch,
+    )
+    write_blobs(blobs, args.out_dir)
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())

Software/tools/fetch_si4684_firmware.py

@@ -0,0 +1,232 @@
+#!/usr/bin/env python3
+"""fetch_si4684_firmware.py — populate Firmware/Si4684-Firmware/ blobs.
+
+DigiRadio firmware — https://github.com/manvalan/DigiRadio
+
+Copyright 2026 Michele Bigi
+SPDX-License-Identifier: Apache-2.0
+
+DAB images are extracted from PE5PVB/SI4684-DAB-Receiver (same as Slice 3).
+FM images are proprietary Skyworks blobs — supply via --si46xx-dir (eval CD /
+dabpi si46xx_firmware folder), --flash-dump (TechniSat-style SPI readout), or
+--from-ugreen-radio-cli (uGreen DABBoard Files_v16.zip / radio_cli ELF).
+
+AN649 Si4684-A10: FM application image fm_radio_5_1_0.bin (or community
+fmhd_radio_5_0_4.bin on Si4688-class boards — verify on hardware).
+"""
+
+from __future__ import annotations
+
+import argparse
+import subprocess
+import sys
+import tempfile
+from pathlib import Path
+
+_TOOLS = Path(__file__).resolve().parent
+if str(_TOOLS) not in sys.path:
+    sys.path.insert(0, str(_TOOLS))
+
+from extract_ugreen_radio_cli import extract_images, write_blobs  # noqa: E402
+
+ROOT = _TOOLS.parent
+FW_DIR = ROOT / "Firmware" / "Si4684-Firmware"
+EXTRACT = _TOOLS / "extract_si4684_blob.py"
+PE5PVB = "https://github.com/PE5PVB/SI4684-DAB-Receiver.git"
+
+FM_CANDIDATE_NAMES = (
+    "fm_radio_5_1_0.bin",
+    "fm_radio_5_0_9.bin",
+    "fmhd_radio_5_1_0.bin",
+    "fmhd_radio_5_0_4.bin",
+)
+
+
+def run_extract(args: list[str]) -> None:
+    cmd = [sys.executable, str(EXTRACT), *args]
+    subprocess.run(cmd, check=True)
+
+
+def clone_pe5pvb(tmp: Path) -> Path:
+    dest = tmp / "SI4684-DAB-Receiver"
+    if not dest.exists():
+        subprocess.run(
+            ["git", "clone", "--depth", "1", PE5PVB, str(dest)],
+            check=True,
+        )
+    return dest
+
+
+def refresh_dab(tmp: Path) -> None:
+    repo = clone_pe5pvb(tmp)
+    run_extract(
+        [
+            "--header",
+            str(repo / "src" / "Si468xROM.h"),
+            "--array",
+            "rom_patch_016",
+            "--out",
+            str(FW_DIR / "rom_patch_016.bin"),
+        ]
+    )
+    run_extract(
+        [
+            "--header",
+            str(repo / "src" / "firmware.h"),
+            "--array",
+            "firmware",
+            "--out",
+            str(FW_DIR / "dab_firmware.bin"),
+        ]
+    )
+
+
+def find_fm_source(si46xx_dir: Path) -> Path | None:
+    for name in FM_CANDIDATE_NAMES:
+        candidate = si46xx_dir / name
+        if candidate.is_file():
+            return candidate
+    return None
+
+
+def import_fm(source: Path) -> None:
+    run_extract(["--copy", str(source), "--out", str(FW_DIR / "fm_firmware.bin")])
+
+
+def import_fm_from_flash(dump: Path, offset: int, size: int) -> None:
+    run_extract(
+        [
+            "--flash-dump",
+            str(dump),
+            "--offset",
+            hex(offset),
+            "--size",
+            hex(size),
+            "--out",
+            str(FW_DIR / "fm_firmware.bin"),
+        ]
+    )
+
+
+def import_from_ugreen(
+    source: Path,
+    *,
+    want_fm: bool,
+    want_dab: bool,
+    want_patch: bool,
+) -> None:
+    blobs = extract_images(
+        source,
+        want_fm=want_fm,
+        want_dab=want_dab,
+        want_patch=want_patch,
+    )
+    write_blobs(blobs, FW_DIR)
+
+
+def main() -> int:
+    ap = argparse.ArgumentParser(description=__doc__)
+    ap.add_argument(
+        "--si46xx-dir",
+        type=Path,
+        help="folder with Skyworks .bin files (eval CD / dabpi si46xx_firmware)",
+    )
+    ap.add_argument(
+        "--flash-dump",
+        type=Path,
+        help="full external SPI dump (TechniSat-style layout)",
+    )
+    ap.add_argument(
+        "--fm-offset",
+        type=lambda s: int(s, 0),
+        default=0x106000,
+        help="FM image offset inside --flash-dump",
+    )
+    ap.add_argument(
+        "--fm-size",
+        type=lambda s: int(s, 0),
+        default=0x81721,
+        help="FM image size inside --flash-dump",
+    )
+    ap.add_argument(
+        "--dab-only",
+        action="store_true",
+        help="refresh DAB + patch only (skip FM)",
+    )
+    ap.add_argument(
+        "--from-ugreen-radio-cli",
+        type=Path,
+        metavar="PATH",
+        help="uGreen Files_v16.zip, radio_cli ELF, or unpacked Files_v16 folder",
+    )
+    ap.add_argument(
+        "--ugreen-all",
+        action="store_true",
+        help="with --from-ugreen-radio-cli: extract patch, DAB, and FM from radio_cli",
+    )
+    args = ap.parse_args()
+
+    FW_DIR.mkdir(parents=True, exist_ok=True)
+
+    ugreen = args.from_ugreen_radio_cli is not None
+    if ugreen and args.dab_only:
+        ap.error("--dab-only cannot be combined with --from-ugreen-radio-cli")
+
+    fm_sources = int(args.si46xx_dir is not None) + int(
+        args.flash_dump is not None
+    ) + int(ugreen)
+    if fm_sources > 1:
+        ap.error(
+            "choose one FM source: --si46xx-dir, --flash-dump, or "
+            "--from-ugreen-radio-cli"
+        )
+
+    with tempfile.TemporaryDirectory(prefix="digiradio-si4684-") as tmp_name:
+        tmp = Path(tmp_name)
+
+        if args.dab_only:
+            refresh_dab(tmp)
+            print("DAB + patch refreshed; FM unchanged.")
+            return 0
+
+        ugreen_full = ugreen and args.ugreen_all
+        if not ugreen_full:
+            refresh_dab(tmp)
+
+        if ugreen:
+            import_from_ugreen(
+                args.from_ugreen_radio_cli,
+                want_fm=True,
+                want_dab=ugreen_full,
+                want_patch=ugreen_full,
+            )
+        elif args.si46xx_dir is not None:
+            fm = find_fm_source(args.si46xx_dir)
+            if fm is None:
+                print(
+                    f"No FM image found in {args.si46xx_dir}; expected one of:",
+                    ", ".join(FM_CANDIDATE_NAMES),
+                    file=sys.stderr,
+                )
+                return 1
+            import_fm(fm)
+        elif args.flash_dump is not None:
+            import_fm_from_flash(args.flash_dump, args.fm_offset, args.fm_size)
+        else:
+            print(
+                "FM image not updated: pass --si46xx-dir, --flash-dump, or "
+                "--from-ugreen-radio-cli.\n"
+                "Skyworks fm_radio_5_1_0.bin is on the Si4684 eval CD "
+                "(see AN649 table 1).",
+                file=sys.stderr,
+            )
+            return 1
+
+    fm_path = FW_DIR / "fm_firmware.bin"
+    if fm_path.is_file():
+        print(f"FM image ready: {fm_path} ({fm_path.stat().st_size} bytes)")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())