11 Commits

Author SHA1 Message Date
cah
f22ee197ab docs(hardening): add wrapper attempt history through v8-v11 + LVS-fix lessons
Document the full wrapper hardening trail:
- Mar 12-13 wrapper_v2/v3/v4 results, mpw_precheck 17/19, and 5/5 GLS pass
- May 7-11 v6-v11 LVS-cosmetic-fix attempts (all seven failed)

The v6-v11 series tried to eliminate the 208 cosmetic LVS pin-match
errors via per-pin conb_1 tieoffs and placement tweaks. All failed
because the errors are a Magic SPICE-extraction limitation (constant-
tied output nets collapse into shared power/ground at extract time),
not a hardening defect. Documented so future sessions don't re-explore
this dead end.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-12 23:13:11 -06:00
cah
1f4b62454f docs: add Run 5-7 hardening results and lessons learned
- Run 5: syndrome pipeline with serial popcount (no improvement)
- Run 6: balanced popcount adder tree — TT timing MET at 50 MHz
- Run 7 series (8 attempts): LAYER_WRITE pipeline exploration
  - LAYER_WRITE split not viable (cell explosion / PnR divergence)
  - Yosys synthesis non-determinism documented
  - Hold margin sensitivity (0.4/0.2 vs 0.5/0.3) identified
  - Run 7h reproduces Run 6 by reusing golden synthesis netlist

Key finding: balanced_popcount synthesis netlist is the golden reference
for all future PnR iterations.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-03-10 19:42:23 -06:00
cah
f2901c6366 docs: add OpenLane hardening results and critical path analysis
Documents 4 hardening runs with timing/area/DRC results. Identifies
SYNDROME state as critical path bottleneck (222 logic levels, 49 ns)
and proposes 2-stage pipeline fix to meet 50 MHz target.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-03-02 17:03:35 -07:00
cah
9a28e30bed docs: add detailed implementation plan for ChipFoundry contest
20 tasks across 8 weeks covering RTL integration, verification,
OpenLane hardening, firmware, PCBA, and final submission.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-25 18:10:38 -07:00
cah
db06a8a481 docs: add ChipFoundry contest submission design
Approach A (minimal viable submission) as execution plan,
Approaches B and C documented as aspirational roadmap.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-25 18:03:55 -07:00
cah
d39b133c76 docs: frame sync runs as PicoRV32 firmware, zero extra RTL
Reuses existing syndrome_wt register and converged flag.
No additional hardware needed on the ASIC.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-24 22:47:49 -07:00
cah
623e5e2e26 docs: add frame synchronization section to project report
Adds section 7 covering preamble-less frame sync using syndrome
screening, which was missing from the original report.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-24 21:54:49 -07:00
cah
87b84f8c75 docs: add project report with architecture diagrams
Comprehensive report for FPGA partner covering:
- System architecture and channel model
- LDPC decoder hardware blocks
- Code optimization journey (5.23 -> 1.03 photons/slot)
- SC-LDPC threshold saturation results
- RTL implementation plan and area estimates

Includes 10 figures: system architecture, channel model,
degree distributions, FER curves, threshold progressions.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-24 21:45:35 -07:00
cah
6d59f853c4 Add comprehensive analysis results document
Covers all five studies: rate comparison, base matrix quality,
quantization sweep, Shannon gap, and frame synchronization.
Includes interpretation, recommendations, and reproduction steps.

Key findings: 9 dB gap to Shannon, matrix degree distribution is
the primary bottleneck, 6-bit quantization validated, frame sync
tractable at ~30 us acquisition cost.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-24 05:01:26 -07:00
cah
b8bff512a4 Add implementation plan for frame sync and code analysis
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-24 04:58:56 -07:00
cah
5f69e2cbec Add design doc for frame sync and code analysis
Covers frame synchronization prototype (acquisition + re-sync)
and four code analysis studies: rate comparison, base matrix
quality, quantization sweep, and Shannon gap computation.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-23 22:42:32 -07:00