How to redirect the printf function to a UART for debug messages

[Supriyash]

It can be especially useful during code development to display messages in a terminal window about various system parameters to help with debugging. An easy way to do that is to use the printf function and redirect the output to a UART for display in a terminal window.

The ST-LINKs embedded on ST Nucleo boards have a virtual com port feature, and we can easily get debugging information on a terminal using printf redirected to the UART of the STM32 connected to the ST-LINK pins used for the virtual COM port.

[Supriyash]

BOT / SPAMMER

[Andrew Neil]

Are you asking a question, or just making an observation (twice)?

The first thing to do - before worrying about printf - is to get the basic UART comms working:

https://community.st.com/t5/stm32-mcus/implementing-uart-receive-and-transmit-functions-on-an-stm32/ta-p/694926

Once that is done, then - and only then -  move on to redirecting printf:

https://community.st.com/t5/stm32-mcus/how-to-redirect-the-printf-function-to-a-uart-for-debug-messages/ta-p/49865

And here's a 3rd-party article on the same:

https://shawnhymel.com/1873/ 

[SofLit]

+ Refer to the board schematics to check which UART is connected to the STLINK to use the virtual comport.