cannot communicate STM32CubeProgrammer with STM32G030 ST Embedded bootloader

[Gaston]

As described in RM0444

I understand my virgin device (STM32G030C6T6) should to connect via UART using STM32CubeProgrammer but as shown I'm not able to establish the first transaction (byte 0x7F reception and answer)

I've checked my custom board hardware and everything (voltages, consumption, PA14-BOOT0 unconnected, TX/RX pins w/100k-pull-up, etc) seems to be okay.

Any hints?

[MM..1]

Are you sure you connect to 

 

[Gaston]

Yes, these pins are connected and the configuration is okay. It's strange. I've connected the device via ST-LINK successfully and everything seems okay.

 

According to the RM if EMPTY-BIT is set Boot is forced to system memory so I expect to answer after a UART 0x7F request.

[Tesla DeLorean]

So 48-pin device.

Check for other potential pin conflicts via AN2606. Chatter on other interfaces at startup by say a GPS/GNSS device might cause that interface to be identified first

It's not so much expecting to receive the 0x7F pattern as it is trying to time the pattern for auto-bauding.