Bootloader via USART1 on NUCLEO-WL55JC1 Nucleo-64 board (MB1389)

[spodshivalov]

I'm trying program FLASH via serial bootloader using  STM32WL55 USART1 

The an2606 indicates that

• USART-RX is PA10 pin, connected to CN7-32
• USART-TX is PA9 pin, connected to CN10-19

I connected the BOOT0 pin to 3.3V

• If after reset I send 0x7f to LPUART via ST-LINK VCOMM I get ACK (0x79) back
• But if after reset I send 0x7F to PA10 using external FTDI232 adapter I'm not getting anything back.  If I check level of PA9 it shows 200mV (the PA10 is 3.3V) with FTDI connected and 0V with FTDI disconnected
• The loopback test on FTDI is working fine, so I don't suspect FTDI malfunctioning

I suspect my board is not properly configured, but could not see anything that would affect PA9 and PA10 configuration. 

Can it be an error in a board documentation, I already spotted one error in table 18, it shows both CN10-35 and CN1-37 connected to PB6, which is probably wrong, one of them must be PB7.

[Mike_ST · Accepted solution]

Hello,

I can confirm the bootloader is working on PA9/PA10,

Here is my setup so you can compare with yours:

>> I already spotted one error in table 18

Thank you for reporting. Internal ticket : #207502

[spodshivalov]

Thanks a lot Mike, I don't know what I was doing wrong. I just disassembled my setup and done it again to copy your photo 1:1. That made a trick!