I just finished a custom board using a RP2040 based on QT RP2040 PY designs. I tried to flash it over USB but the CPU is not recognized, even using MU editor (I developped everything using circuitPython and I would like to use the same configuration with my board ; drag and drop files is pretty convenient…)
I check all pins : voltage levels and pinout (including USB) is correct.
I tried to tie down RUN / CS of the flash but nothing changed
Is there a first flash to achieve using SWD ? Like for installing a kind of USB bootloader or anything ?
Anybody can help ?