General • Re: Pico2 RP2350: can't use GPIO26/27 as uart

Is your Pico2 RP2350 board original or you made a clone/customized board?

It is the original.

Hi, I'm trying to use the GPIO pins 26 and 27 as TX and RX for UART1, which according to the RP2350 Datasheet is possible (Function 11 for those pins).

In your description of how you generated the program, you don't mention setting Function 11, only setting the pin numbers.

In standard code, particularly written for RP2040, function 2 will be selected for UART - giving you UART1_CTS and UART1_RTS on your chosen pins. That sounds consistent with the results you are getting.

Thank you, that was it! I saw the existing calls to `gpio_set_function(..., GPIO_FUNC_UART)` and thought that was the correct value, as I want to use the pins as UART. I did not realize that this maps exactly tu the function numbers in the datasheet, and that there's other UART-related entries in the same row. So setting that to GPIO_FUNC_UART_AUX, everything works exactly as expected!

Statistics: Posted by csierra — Tue Apr 15, 2025 5:01 pm

---