Ken Boak

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5 years, 1 month 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:

Last updated: 30 Mar 2019
Affordable and flexible platform to ease prototyping using a STM32F302R8T6 microcontroller.
posted by toshiki goto 31 May 2016
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3 Answers

Armelle DubocST
3 years, 6 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.

Post a comment on this answer Accepted Answer

Hello. Thank you Adu.

I will wait for the pull request is merged.

posted by toshiki goto 31 May 2016

/media/uploads/gototoshiki/uart.gif

Hello.Adu. I checked your fix code.(code of github)

I have succeeded in using the Port PB_10 as UART.

Thank you.

posted by toshiki goto 01 Jun 2016
toshiki goto
3 years, 6 months ago.

I also got up the same problem.

toshiki

Post a comment on this answer
ST support team
3 years, 6 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

Post a comment on this answer

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 toshiki goto 30 May 2016