Files
FPGA-Neural/hardware/v2/logs
micheleandClaude Sonnet 5 8e014d8d49 V2.0.0 hardware freeze - single SDRAM
FASE #1 hardware freeze for FPGA-Neural V2, N4/P8, single external
SDRAM (Alliance Memory AS4C4M16SA-6TIN) serving weights, activations,
and results through one physical sdram_controller.v instance. Removes
the PSRAM dependency (hardware/v1/rtl/psram_controller.v +
memory_interface.v) from the V2 physical path entirely -- V1 itself
remains fully unmodified, the golden reference.

New RTL: sdram_unified_backend.v (2-way W/AR arbitration over one
SDRAM controller, real per-byte DQM write masking added to
sdram_controller.v for correct single-byte result writes with no
read-modify-write), nms_neural_multiprocessor_sdram_unified.v (the
frozen top-level). Two real bugs found and fixed via full-system
testing before being accepted (ERR-0023): a deadlock and an off-by-one
data-shift bug in the new arbitration logic.

Real results: N=4 and N=2 D-Stress bit-exact (256/256 neurons), 40
real AUTO REFRESH events interleaved with zero corruption, real
Yosys+nextpnr-ecp5 synthesis/P&R for LFE5U-45F-8CABGA381 (149/245
TRELLIS_IO, a real 45-pin reduction from the prior dual-memory
design). Timing is MARGINAL (1/8 P&R seeds >=80MHz), reported honestly
rather than masked by the best seed.

Real, sourced ball-level pinout for the SDRAM bus + clk/rst (39/149
signals, P&R-verified) using the official Lattice ECP5U-45 pinout CSV
found on disk during this step's own pre-commit review -- corrects an
earlier draft that wrongly assumed no real pinout data was available.

Chip readiness: NO. Real, disclosed blockers remain (no physical host
interface exists yet -- the RTL's own reg_* ports are a 110-pin raw
test-harness bus; clock source/PLL decision; power/configuration
component selection) -- see hardware/v2/docs/{HARDWARE_FREEZE,
CHIP_READINESS,OPEN_ITEMS}.md for the complete, itemized status.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013xXuuRUWZScuo1DeYJxs3v
2026-09-06 13:39:55 +02:00
..

Formato dei log V2

Regola non negoziabile (docs/v2-description.md §25-29): ogni attività significativa (modifica, simulazione, sintesi, benchmark, decisione, errore) deve essere registrata. Nessun log viene mai sovrascritto o troncato — solo append. Nessun ID esperimento (EXP-XXXX) o decisione (DEC-XXXX) viene mai riutilizzato, anche se il risultato è un FAIL.

File

  • development.log — log principale di sviluppo, un'entry per ogni sessione di lavoro/milestone (creazione file, refactor, avanzamento roadmap).
  • architecture.log — decisioni e note di architettura a grana fine (non scelte finali — quelle vanno in decisions.log — ma esplorazioni, alternative considerate, vincoli scoperti).
  • simulation.log — ogni run di simulazione (Icarus/Verilator): test, vettori, cicli, PASS/FAIL, confronto bit-exact con V1, stall/memory-wait.
  • synthesis.log — ogni run Yosys: LUT/FF/DSP/BRAM, warning, problemi CHECK.
  • timing.log — ogni run nextpnr-ecp5: Fmax, percorso critico, WNS/TNS se disponibili. Fmax "ufficiale" di una configurazione = solo da qui, mai da simulazione o stima.
  • benchmark.log — tabelle di confronto per configurazione (Fmax, MAC/cycle, cycles/neuron, utilization, ecc.), sempre con etichetta THEORETICAL/SIMULATED/SYNTHESIZED/POST-P&R.
  • decisions.log — decisioni architetturali importanti, formato DEC-XXXX (vedi docs/v2-description.md §27).
  • experiments.log — registro principale, un EXP-XXXX per ogni esperimento end-to-end (config → sim/synth/timing → risultato), rimanda a reports/experiments/EXP-XXXX/.
  • errors.log — errori/bug/regressioni incontrati durante lo sviluppo V2 stesso (non i bug V1, già chiusi in hardware/v1/docs/validation/bugs.md).

Campi minimi per entry (§26)

timestamp, experiment_id (se applicabile), git_commit, session/agent,
module, configuration, action, reason, command, result, errors, decision,
next_action

Per synthesis/timing aggiungere: LUT, FF, DSP, BRAM, Fmax, critical path, WNS/TNS. Per simulazione: test, vectors, cycles, PASS/FAIL, bit-exact result, stall cycles, memory wait, utilization.