Test with USART or UART

[xhadow13]

Hello everyone I'm new here and new to developing on quadcopters! I was wondering if anybody could help me out. What I want to do in the end is connect a camera through serial communication through the UART on the Crazyflie, and have it save to a microSD card through SPI communication. For now I just want to test the UART actually sends out a signal. However I have been trying to find the functions or files that use the UART, in particular the UART4. I found the uartsyslink.c file but I believe that communicates with the other mcu correct? I've been trying to use the STMuart.c file and cant seem to get a signal out. Any help would be appreciated. Thanks.

[tobias]

The plan is to make the expansion port a lot easier to use but first we have to merge the Crazyflie 1.0 and 2.0 branches which is ongoing. Until then it requires a bit more work.

The uart_syslink already contain most code needed to get a UART up and running. I would copy it into a new file and remove the stuff that is not needed. In uart_syslink.h there are already defines for the EXT_UART1 so you can use that.
If you will be using interrupt don't forget to update the interrupt function in nvic.c

Hope this gets you going!