Changing the default UART settings generates a broken cmake configuration.

[Fluxward]

Hi,

Here's what I've tried.

step 1 (control):
Use the GUI to generate an empty project. The settings I used were:
Board type = pico
no library options
console over UART
no code options set
build run after generation
create vs code project
picoprobe debug

This step created an empty project which successfully built, both after the project was generated and through manual testing.

step 2 (broken):
The only things I changed were that I set:
PICO_DEFAULT_UART = 1
PICO_DEFAULT_UART_RX_PIN = 27
PICO_DEFAULT_UART_TX_PIN = 26

Cmake runs without errors, but the subsequent make does not succeed.

[lurch]

Section 1.4.3. in https://datasheets.raspberrypi.com/rp2040/rp2040-datasheet.pdf shows that pin 26 is UART1 CTS and pin 27 is UART1 RTS, so these can't be used as TX and RX pins.