B-WL5M-SUBG1 Sigfox_AT_Slave Application LPUART has wrong pin configurations

Mona-Roza · ‎2025-10-09

As you can see below picture, B-WL5M-SUBG1 Connectivity Expansion Board's UART pins are PC0 and PC1:

But in the STM32Cube_FW_WL_V1.3.1 repository Sigfox_AT_Slave application for B-WL5M-SUBG1 describes uart pins are PA3 and PA2:

So in this case, application's UART AT interface doesn't work. Buf if you change LPUART1 pin configurations, it works fine:

Thank you for your interest.

Mahmoud Ben Romdhane · ‎2025-10-09

Hello @Mona-Roza ,

Let me thank you for your feedback.

Your request is under investigation, and I will get back to you ASAP.

Thanks.

Mahmoud

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Issamos · ‎2025-10-09

Hello @Mona-Roza

As you can see on the Readme file of the example:

« Connect the Connectivity Expansion Board to your PC with an external STLINK-V3SET. »

and the STLINK-V3SET is usually connected to the board throw the STDC14 connector (CN3). According to the table 14 of the UM3127: the LPUART is connected to PA2 and PA3:

so, the example works fine as it is if you are using the CN3. If you want to use the CN1, you should change the LPUART pins to PC0 and PC1 but this is not the official implementation.

Best Regards.

II