I started checking the 9-pin Arduino header change, but this run is blocked because the last request arrived after the prior task state had already ended. The required next action is to replace the current J7 10-pin ARDUINO_EXT header with a 9-pin male header, wire pins 1–9 as specified, move it to the bottom-center edge facing downward, and update Design Notes.
Confirmed. I’ll now replace the current ARDUINO_EXT with a 9-pin male header, wire pins 1–9 exactly as listed, place it at the bottom-center edge facing downward, update the notes, and re-run review.