JLink Intermittently Resetting Device via Reset Pin

Hello,

My Jlink Base Compact is resetting my device (STM32U585QI) approximately every 8-10 seconds via the reset pin according to the firmware on my device.

This problem began when I started using my new laptop, a Macbook Pro with an M4 chip running Sequoia 15.5. My previous Macbook with the same OSX version and M1 chip does not exhibit this behavior.

I recently uninstalled all segger tools and software from my computer and the issue stopped. Immediately upon reinstalling them my device started resetting. I didn't even start an application or interact with the JLink. I have ensured the OSX version, JLink Firmware, and JLink tool versions are all the same.

Specifications:
Platform: OSX
JLink Type: JLink Base Compact
JLink software version: 7.98b (although I have tried 8.36)
JLink Firmware: V11
Target Device: STM32U585QI

Attempted Solutions:

• Reinstall JLink Firmware
• Remove all JLink/SEGGER files from system and reinstall JLink tools 7.98b
• Different USB ports, i.e. USB Micro on Jlink to usb a hub and JLink to usb A to C adapter directly into PC USB C port
• Disconnecting and reconnecting connections between the target the device and PC
• Tried a script that continually set the rest pin high while target device was connected
• Set VTREF to a static value instead of letting it auto negotiated, tested values of 1.8V and 3.3V
• Our device uses an intermediate debug board, i.e. PC connects to JLink, JLink connects to debug board, debug board connects to target device, and I have tried multiple debug boards and experienced the same issue

Please let me know what additional configuration or debug info can help. Thank you.

I got it to not reset anymore. I had a system service that started the JLinkGDBServerCL for a different device (an MK82). Disabling that stopped the device from resetting. However I do not have access to the UART/RTT over the JLink connection which I would expect.

Hi Simon,

I found the resolution to the issue was I had an old system service on my machine that was running the JLinkGDBServerCL. Even though it was for a different device, it was still causing some sort of interference with my normal JLink connection. That's still a bit of a mystery to me, but removing the service did solve it.

The issue I was running into to with the uart was because while I was trying to debug the issue I disabled the VCOM port. That's my bad

Kind Regards,

Grant