My USB-C Nucelo boards cannot detect ST-Link

[kag_embedded]

I just received a NUCLEO-H503RB dev board, and while attempting to use the GPIO_IOToggle example program to test out the board, I could not run the debugger due to the error "ST-Link not detected." I went back to my NUCLEO-H7S3L8 board, it now receives the same error. A few days ago, I was able to program it.

I was able to detect the ST-Link with my NUCLEO-F446RE board.

Do I need to reinstall ST-Link or is there a way to force a firmware update on my two NUCLEO USBC dev kits?

Thank you.

[Chris21]

Are you using the correct USB connector? 

Labeled USB STLK.

[kag_embedded]

I have tried both USBC ports. One port, the LEDs do not light up. The other USBC port, near the header pins with the ST-LINK pins which are shorted together, blink through what appears to be a boot up sequence and then LED3 blinks at a regular pulse rate.

What should I try next?

Thank you.

[Chris21]

Not sure, my NUCLEO-H503RB worked immediately. 

"the header pins with the ST-LINK pins which are shorted together"?

Which pins are those?  JP1 should not have a jumper.

[kag_embedded]

JP5, SW_STLK pins are shorted to +5v.

[Chris21]

5V_STLK shorted to +5V is the normal use case, board powered from ST-LINK USB connector.

[kag_embedded]

What should I try next?

Is there a way to force a refresh of the NUCLEO's firmware? On the Silicon Labs kits, you can force an update of the firmware in situations similar to this.

[kag_embedded]

Would using JP1 to reset the STLNK be worth a try? If yes, do I just short it out and then remove the short?

[Chris21]

I believe STM32CubeProgrammer can be used to reprogram the ST-LINK, but I have not needed to do that.

[Chris21]

"do I just short it out and then remove the short?"  

That will reset the ST-LINK MCU, I don't expect it will solve your problem, though.