Pro Micro RP2040 using D2 and D3 for UART?

Development Boards Raspberry Pi
1

I am trying to drop a Pro Micro RP2040 on a split keyboard pcb, BFO-9000, designed to use a standard Pro Micro. The PCB uses the Pro Micro RP2040’s D2/D3 pins for UART. I am trying to run uart = busio.UART(tx=board.D3, rx=board.D2) but its erroring out with “invalid pins” Flipping it to be ```
uart = busio.UART(tx=board.D2, rx=board.D3)


PCB Schematic: [https://github.com/keebio/keebio-docs/b ... ematic.pdf](https://github.com/keebio/keebio-docs/blob/master/static/schematics/BFO-9000%20Schematic.pdf)
2

Looking at your schematic, I don’t see anything that needs UART at all. Just use those two pins as GPIO.

3

Those two pins are used (needed?) for UART to communicate between the two halves of the keyboard over TRRS.

4

So after looking at the RP2040 datasheet again I now understand that D2 and D3 are only for UART CTS/RTS so I am pretty positive I cannot use them to communicate over UART with my pcp.