neuron_memory.v only handled a single neuron. Added an N_NEURONS
parameter (default 1, fully backward compatible) and a memory-bound
neuron loop: X is read once (shared layer input), and for each
neuron in turn W and bias are re-read from PSRAM and fed to a
single, reused neuron_parallel instance -- no change to the
validated compute datapath (neuron_parallel/mac8/mac_unit).
Addressing follows layer.v's neuron-major convention: neuron n's
weights live at w_base + n*N_INPUTS bytes, its bias at
bias_addr + n. Output changed from a single `y` port to a packed
`y_bus` (DATA_WIDTH*N_NEURONS bits, neuron-major), matching
layer.v's y_bus.
- rtl/neuron_memory.v: N_NEURONS parameter, neuron_index/
w_group_base/bias_group_addr tracking, y_reg[] array assembled
into y_bus, STATE_WAIT_N now loops back to STATE_READ_W for the
next neuron instead of finishing after one.
- sim/neuron_memory_tb.v: updated to the new y_bus port
(N_NEURONS=1 explicit); all 5 existing tests still pass unchanged,
confirming backward compatibility.
- sim/neuron_memory_multi_tb.v: new end-to-end test (full
memory_interface + psram_controller + psram_model stack) with
N_NEURONS=3, validating per-neuron addressing and a single done
pulse at the end of the sequence (scale, larger value, ReLU).
- Full regression re-run: all existing testbenches still pass.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WQV3vS9TXaGDJ5cRfnfidt
preload_vector and preload_weights wrote using base as a word address
instead of a byte address (base + (k>>1) instead of (base>>1) + (k>>1)),
misaligning X/W data in PSRAM relative to what int8_memory_access expects.
Also adds a PATTERN test (X=1..32) to exercise mixed even/odd byte reads
and catch this class of bug going forward.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WQV3vS9TXaGDJ5cRfnfidt