The 93LC46B's DO and DI were both tied directly to EEDATA, causing
drive contention during EEPROM read turnaround. Per the FT2232H
datasheet ("Connect directly to Data-In of the EEPROM and to Data-Out
of the EEPROM via a 2.2K resistor. Also, pull Data-Out of the EEPROM
to VCC via a 10K resistor"):
- U7.4 (DO) moved onto new net EE_DO
- R30 2.2k (UNI-ROYAL 0402WGF2201TCE, LCSC C25879, Basic) between
EE_DO and EE_DATA
- R31 10k (0402WGF1002TCE, C25744) pull-up from EE_DO to 3V3
- EEDATA -> DI (U7.3) stays direct
Schematic only; R30/R31 still need placing near U7 in the PCB rework.
Verified: ERC 0, EE_DATA = {U8.61, U7.3, R30.2}, EE_DO = {U7.4, R30.1,
R31.2}, R31.1 on global /Power/3V3 (no orphan local net), netlist
115 vs BOM 114 differing only by the deliberate J3 exclusion.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Roflin
Dennis Brentjes