Disco-L072 programming using the ST-Link programmer doesn't work. Any tips ?

[Julien Weber]

Dear community,

I'm trying to use the CN12 SWD connector and the ST-Link/V2 programmer to flash my Disco-L072CZ-BLRWAN1 board.Next, I want to program my own board with a Murata Cmwx1zzabz module but first I want to know how to do it properly with the ST-Link/V2 and the Disco board.

I removed the 2 connectors from the dev-board (CN8) in order to use the ST-Link connector and not the ST-Link from the USB. Regarding the (UM1075) user manual ST-Link in-circuit programmer, I connected the signals following :

MCU VDD => VDD_Target

GND => GND

SWDIO => SWDIO

SDWCLK => SWCLK

NRST => NRST

TRACESWO => SWO

My ST-Link firmware is up to date. I'm trying to use the ST-Link utility first but it seems the target is not recognize (connection between ST-Link and the MCU).

Does the MCU is powered by the programmer when the programmer is flashing it or do I have to power the board using the 3V3 and GND connectors?

Best regards.

[Tesla DeLorean · Accepted solution]

You'd want to disconnect the on board ST-LINK, and then use the target side SWDIO and SWCLK pins, not the output header.

This is a topic area that has been covered multiple times. Review the board schematic.

[Julien Weber]

You're right, my aim was to have the lowest power consumption so I removed the SB37 (used for NRST) then when I tried to use the STM32 Utility, it didn't work. Now I manage to connect it properly by using the reset button just before the connection.

Thank you for your time!