ST-Link connection problems plaguing project progress

[LysAn]

Hello,

we have purchased multiple Nucleo H723ZG and H7A3ZI-Q. Since the beginning, connection problems with ST-Link are plaguing the project. It is impossible to reliably debug, because connection with the host can't be established via USB. We have checked all possible sources (like different computers, cables, docks, ports, software, et.c.), but the issue sporadically appears, even with brand new boards out of the box, which costs money.  Other users face similar issues and I wonder what steps ST wants to take.

Best regards

[Javier1]

This smells like grounding issues. :D
>>Other users face similar issues and I wonder what steps ST wants to take.
I personally never had those issues, stlinks old and new are realiable.

Seeing your other posts it looks like youre getting started with ST, my money is on burnt nucleo board due to high voltage apølied to analog pins or defective project grounding.

Show us some pictures

Try this, use stlink with a laptop Pc unplugged from its wall charger, do your problems magically solve?

Are you conecting something else to your Nucleo H723ZG, maybe a oscilloscope probe?

[TDK]

Something with your setup isn't right. You shouldn't be having problems with debugging. More clarity into the setup and the exact problems you're having (exact error messages, etc) would be helpful. Unlikely that this is a board problem.

[Andrew Neil]

https://community.st.com/t5/stm32-mcus/how-to-solve-debugger-connection-issues/ta-p/49693?search-action-id=45817862874&search-result-uid=49693

https://community.st.com/t5/stm32-mcus/faq-possible-communication-failure-between-stlink-v3-and-some/ta-p/736578?search-action-id=45817970751&search-result-uid=736578

[Pavel A.]

Connect the board thru a good USB 2.0 hub. Powered hub is even better.

[Karl Yamashita]

As everyone seem to state, there must be something wrong with your setup. I've never had an issue with the Nucleo-H723ZG. 

• Show the errors you are getting when trying to make connections.
• Is LD4 and LD6 LED's On when the USB cable is plugged in?
• Is the VCP not working as well?
• Can STM32CubeProgrammer make connection?
• Are there any external devices that you have connected to the Nucleo?

[LysAn]

Thanks for your input. Here is a typical example, new Nucleo-Board just unboxed. This setup will sometimes work, sometimes not.

• LD4 will mostly stay red, sometimes turn green.
• LD6 usually stays off
• CubeProgrammer will mostly not connect
• STLinkUpgrade will mostly fail
• Board will show up in command line terminal as/dev/tty.usbmodem213403
   
• 

[Javier1]

>>will mostly

If this was happenning to me i would try with another PC another usb cable and another nucleo board, and then slowly one by one introduce the old setup back.

[Pavel A.]

Ah, that's a MAC! Maybe even a new ARM based MAC. Please try a powered hub. Though it definitely may hurt the minimalism of the setup and overall aesthetics. (If the hub will help, you can hide it behind the screen or paint it white).

If possible, please share logs from the debug terminal pane of CubeIDE and other useful logs. Look in the system logs of OS/X if there's anything indicating USB issues.

[Javier1]

>>paint it white