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6 years, 5 months ago.
Serial problem - no Tx to PB_10
Hi,
I wish to use USART 3 on the STM32F302 Nucleo board.
I initialise using
Serial usart3(PB_10, PB_11);
but there is no response from the Tx pin on PB_10. It just sits at high level.
I have successfully used USART1 as follows, but USART3 does not appear to initialise
Serial usart1(PA_9, PA_10);
Any help appreciated
Ken
Question relating to:

3 Answers
4 years, 10 months ago.
Hello, I have validated that replacing UART3_BASE by USART3_BASE in the file : targets/hal/TARGET_STM/TARGET_STM32F3/serial_api.c fixes the issue for PB_9 and PB_10
I have done a Pull request in github, you should be able to use it soon. Thank you for the issue notification.
4 years, 10 months ago.
Hi,
Could you please add the following define and let me know if it is working as expected or not:
#define UART3_BASE USART3_BASE
Thank you for reply. But it did not work even if you add it.(I checked with an oscilloscope.)
The results are below.
Serial SIRIAL(PB_9, PB_8); ->NG
Serial SIRIAL(PB_10, PB_8); -> NG
Serial SIRIAL(PA_9, PA_10); -> OK
Signal of Pin PB_9 PB_10 is always "H".
We will continue to investigate. If you have same tips, please tell me.
toshiki
posted by 30 May 2016