B-G474E-DPOW1 debug using Tag-connector CN10 not working

[Keano16]

Hi,

I have started working with the B-G474E-DPOW1 (STM32G474RE). The intention is to use the G474 in a custom design.

I can connect and use the board fine with the on-board debugger, but I want to use the TAG-Connector 10-pin header (CN10, as this is the plan for the target board later), but the connection is not recognised in the STM32CubeProgrammer. Programmer output::

13:36:00 : UR connection mode is defined with the HWrst reset mode
13:36:00 : ST-LINK SN : 39FF6.....
13:36:00 : ST-LINK FW : V2J45S7
13:36:00 : Board : --
13:36:00 : Voltage : 0.06V
13:36:00 : Error: No STM32 target found! If your product embeds Debug Authentication, please perform a discovery using Debug Authentication

I have followed the steps in the UG to disable the on-board STLINK-V3E (Section 9.2 STLINK-V3E physical disconnection) and I am using an external ST-LINK/V2 ISOL with a Tag-Connect adapter and cable (TC2050-ARM2010 adapter and TC2050-IDC cable)

• JP6 - Connected, STLK NRST -> Gnd
• SW1, Octal, all inactive i.e. switches up
• JP7 - removed
• Board powered with CN3 and LD6/LD7 lit, as expected

Do I need to do something else or have I misunderstood something to allow me to debug in this way?

Many thanks in advance for any help provided

[ELABI.1]

Hello @Keano16 

Maybe your MCU is not supplied. Could you please double check if IDD jumper is already fitted. Also, can you try on another device to check if you have the same issue. Finally, I think this Article can help you on how to solve debugger connection issues.

Best regards,

ELABI.1

[Keano16]

Thank you @ELABI.1 

I think the target is powered correctly as the IDD jumper is fitted and I have power LEDs lit, but the voltage displayed in the STM32CubeProgammer is almost 0V - should this be ~3.3V even when using Tag Connect?

In terms of the SW, the STLINK is detected correctly. I can also connect to the Discovery board with the on-board debugger, so that HW seems fine. I do not have another board to connect to the external ST-LINK/V2 unfortunately.All the SW is worrking correctly as per your link when using the on-board debugger.

Generally, is it correct to state that when the 10-pin TAG connector is connected to the target it automatically works with the STM32CubeProgrammer using the SWD interface? I want to check if there is anything that I may have missed in terms of how this is supposed to work.

[Keano16 · Accepted solution]

I located another ST-LINK on a Nucleo board and wired it manually to the test board.

The STM32Cube programmer worked immediately, so the issue here seems to have been my new ST-LINK V2 (official V2 ISOL model from ST). It appears to have been faulty out of the box.