Addresses findings from docs/DEVELOP_AUDIT_2026-04-19.md:
P0 source-level:
- F-4.3 ADAR1000_Manager::adarSetTxPhase now writes REG_LOAD_WORKING
with LD_WRK_REGS_LDTX_OVERRIDE (0x02) instead of 0x01. Previous value
toggled the LDRX latch on a TX-phase write, so host TX phase updates
never reached the working registers.
- F-6.1 DDC mixer_saturation / filter_overflow / diagnostics were deleted
at the receiver boundary. Now plumbed to new outputs on
radar_receiver_final (ddc_overflow_any, ddc_saturation_count) and
aggregated into gpio_dig5 in radar_system_top. Added mark_debug
attributes for ILA visibility. Test/debug inputs tied low explicitly.
- F-0.8 adc_clk_mmcm.xdc set_clock_uncertainty: removed invalid -add
flag (Vivado silently rejected it, applying zero guardband). Now uses
absolute 0.150 ns which covers 53 ps jitter + ~100 ps PVT margin.
P1:
- F-4.2 adarSetBit / adarResetBit reject broadcast=ON — the RMW sampled
a single device but wrote to all four, clobbering the other three's
state.
- F-4.4 initializeSingleDevice returns false and leaves initialized=false
when scratchpad verification fails; previously marked the device
initialized anyway so downstream PA enable could drive a dead bus.
- F-6.2 FIR I/Q filter_overflow ports, previously unconnected, now OR'd
into the module-level filter_overflow output.
- F-6.3 mti_canceller exposes 8-bit saturation counter. Saturation was
previously invisible and produces spurious Doppler harmonics.
Verification:
- 27/27 iverilog testbenches pass
- 228/228 pytest pass (cross-layer contract + cosim)
- MCU unit tests 51/51 + 24/24 pass
- Remote Vivado 2025.2 build: bitstream writes; 400 MHz mixer pipeline
now shows WNS -0.109 ns which MATCHES the audit's F-0.9 prediction
that the design only closed because F-0.8's guardband was silently
dropped. ft_clkout F-0.9 remains a show-stopper (requires MRCC pin
move), tracked separately.
Not addressed in this PR (larger scope, follow-up tickets):
F-0.4, F-0.5, F-0.6, F-0.7, F-0.9, F-1.1, F-1.2, F-2.2, F-3.2, F-4.1,
F-4.7, F-6.4, F-6.5.
Replace direct !reset_n async sense with a registered active-high reset_h
(max_fanout=50) in nco_400m_enhanced, cic_decimator_4x_enhanced, and
ddc_400m. The prior single-LUT1 / 700+ load net was the root cause of
WNS=-0.626 ns in the 400 MHz clock domain on the xc7a50t build. Vivado
replicates the constrained register into ≈14 regional copies, each driving
≤50 loads, closing timing at 2.5 ns.
Change radar_system_top default USB_MODE from 0 (FT601) to 1 (FT2232H).
FT601 remains available for the 200T premium board via explicit parameter
override; the 50T production wrapper already hard-codes USB_MODE=1.
Regression: add usb_data_interface_ft2232h.v to PROD_RTL lint list and
both system-top TB compile commands; fix legacy radar_system_tb hierarchical
probe from gen_ft601.usb_inst to gen_ft2232h.usb_inst.
Golden reference files (rtl_bb_dc.csv, rx_final_doppler_out.csv,
golden_doppler.mem) regenerated to reflect the +1-cycle registered-reset
boundary behaviour; Receiver golden-compare passes 18/18 checks.
All 25 regression tests pass (0 failures, 0 skipped).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Jason
NawfalMotii79