STM32CubeProgrammer Unable to detect ST-LINK ISOL

[JPFF]

Hi!

I'm having trouble connecting to an STLINK ISOL via STM32CubeProgrammer. The STLINK is authentic, I purchased it from digikey.

 

The programmer is detected under Device Manager. The programmer's LED remains static red at all times.

 

Sometimes STM32CubeProgrammer detects an STLINK device, but when I click connect it gives 

10:40:01 : STM32CubeProgrammer API v2.21.0 | Windows-64Bits
10:40:09 : UR connection mode is defined with the HWrst reset mode
10:40:14 : ST-LINK error (DEV_USB_COMM_ERR)
10:40:14 : Error: Problem occured while trying to connect

 

Changing to software reset

10:41:23 : UR connection mode is defined with the SWrst reset mode
10:41:28 : ST-LINK error (DEV_USB_COMM_ERR)
10:41:28 : Error: Problem occured while trying to connect

 

And then, when I click refresh interfaces the STLINK interface disappears.

Disconnecting from USB and reconnecting, when I try to update firmware and open device in update mode it gives

Error connecting to device ST-LINK/V2 (error 0x21); check the USB connection and refresh the device list

 

The firmware version is: V2J29S7

[TDK]

Solid red means enumeration worked. Try a different cable and remove any hubs in the chain.

[JPFF]

Hi!

 

I tried as suggested with a different cable, one that was from a hard drive that has additional USB-A for power instead of the original USB cable that came with the STLINK ISOL, and the behavior remains the same.

 

Could 'hardened' Windows Defender settings prevent the programmer from working correctly or STM32CubeProgrammer from establishing a connection to it?

[Andrew Neil]

More things to try:

https://community.st.com/t5/stm32-mcus/how-to-solve-debugger-connection-issues/tac-p/698105/highlight/true#M956

 

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@JPFF wrote:

Changing to software reset

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That only affects the SWD/JTAG connection from the ST-Link to the Target microcontroller - it won't make any difference to the USB connection between the Host and the ST-Link.

 

Is the ST-Link connected to a Target?

[JPFF]

It is not connected to any target...

I'll connect it and try again. Does it need to be connected to a target to be able to connect to the programmer? 

[Andrew Neil]

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@JPFF wrote:

Does it need to be connected to a target to be able to connect to the programmer? 

---

Shouldn't do.

[JPFF]

I connected my STLINK/V2 to another desktop running Ubuntu 24.04, running STM32CubeProgrammer as unprivileged user it doesn't list any STLINK device and outputs an error CONN_ERR, but after running STM32CubeProgrammer as root it effectively detects the STLINK without any issues. I tried upgrading firmware but it requires that the STLINK be in DFU mode.

I could be wrong, but this seems like an issue with Windows blocking something.

[JPFF]

Okay, I fixed my own problem. After updating the firmware with this utility in Windows the STLINK is now detectable and reads target voltage

https://www.st.com/en/development-tools/stsw-link007.html