Per the WIZnet W5100S reference schematic (note 4: "to avoid the 100M
overshoot, place the 49.9 resistors and 0.1uF capacitor near the MDI
pin"): R26/R27 (49.9R 1%) from TXOP/TXON to a common node bypassed by
C18 (100nF) to GND, and R28/R29 + C19 likewise for RXIP/RXIN. Attached
on the PHY-side nets (chip side of D4/D5). BOM fields populated
(UNI-ROYAL 0402WGF4999TCE / LCSC C25120, Samsung CL05B104KO5NNNC /
C1525). Optional 3.3R series dampers deliberately omitted.
Schematic only - the 6 footprints still need placing/routing next to
U11 pins 2/3/5/6 (Update PCB from Schematic). DRC parity reports
exactly those 6 missing footprints and nothing else.
Verified: ERC 0, netlist 107->113 components, termination nets match
the reference topology.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
SP1 DO/DI naming is console-perspective (verified against SD Gecko and
SD2SP2 wiring): pin 6 DO = GC data out = adapter MOSI input, pin 9 DI =
GC data in = adapter MISO output. The design doc's SP1 table had the
roles reversed and the schematic followed it, putting the FPGA's MISO
driver on the GC-driven DO line (bus contention).
Fix keeps all PCB routing identical:
- Swap net names EXI_MOSI(_RAW) <-> EXI_MISO(_RAW) across exi/Fpga/root
sheets and the PCB (also renames the D2 PUSB3AB6 channel assignments).
- Swap R21 (22R) <-> R25 (33R) identities between the two footprint
positions so 33R stays on the FPGA-driven MISO line, 22R on the MOSI
input.
- Correct the SP1 pin table + MISO-tristate note in
docs/gc_bba_fpga_design.md (root cause).
Resulting board pin map (for the future board PCF): EXI_MOSI = FPGA
pin 4 (IOB_8a, input), EXI_MISO = pin 3 (IOB_9b, output).
Verified: ERC 0, DRC 0 errors with schematic parity 0, netlist shows
J3.6(DO)->R21->pin 4 and J3.9(DI)->R25->pin 3.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
- Remove stale lowercase power.kicad_sch (pre-rework draft; live sheet is
Power.kicad_sch). Both paths were git-tracked, which on a case-insensitive
Windows checkout makes them one file on disk - deleting the stale one also
deleted the live one, and restoring the live sheet resurrected the stale
path at the next commit. Removing the path from the index breaks the loop.
- Remove re-bba-rb.kicad_pcb.old.* leftovers (recoverable from history).
- Restore hardware/re-bba-rb/datasheets/ (deleted accidentally by 3547302)
and add the two missing datasheets: TPS22810 (power) and PUSB3AB6 (exi).
- Add hardware/re-bba-rb/TODO.md capturing the 2026-07-17 review findings
(EXI DO/DI swap, missing W5100S MDI termination, FTDI EEPROM resistors,
iceprog pin mismatch, PR1 margin, BOM/ordering notes); referenced from
CLAUDE.md.
Verified after cleanup: ERC 0 violations, netlist identical (107 components).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Roflin