I'm working with the Nucleo-144 (STM32F429ZI) on a multi sensor system. I am developing using STM32CubeIDE.
One of our sensors communicates over UART and we have broken out UART4 such that PC10 is TX and PC11 is RX. This configuration is suggested as an alternative in Cube.
The problem is that we can't get any output from TX. I don't know if RX is working, because I haven't tested, but I have extensively tested TX and it doesn't do anything except resting HIGH. I have tried this using the Nucleo Framework in Cube, as well as using the Nucleo board as a simple 429ZI chip. I've used the board in-circuit and out-of-circuit. I've scoped it, logic-analyzed it, and it never talks. I have it doing a simple HAL_UART_Transmit() sending 'U' or anything else that comes to mind, in a loop that also flashes an LED, so I know that the program loop is functioning.
I've been so hell-bent on making this work, that I've turned off everything else, running a bare-bones program with nothing but a while(1) event loop.
I'm pretty familiar with HAL tools for UART, and I'm currently having success with UART3 and UART6. So, this isn't a general question about how UARTs work. It's specifically about UART4 on this chip. My coworker on the project has had the same problem, and between us, working together and independently, we are stuck on this one peripheral.
Any help would be greatly appreciated. Thanks.
