Hi, I noticed that when debugging any board with STM32L152(designed with myself or ST Discovery board) using ST-Link V2 in keil, it is very sensitive to noise.If you put a probe on the ground of the board, it will stop debug session with an error "Cannot access target shutting down debug session". However MCU continues operation with no problem. If you know the reason please share it with me, thanks.
I don't use your board/processor/probe but maybe you should tell us a bit about how your board is powered, and how it shares ground with the PC, and if there are any special I/O etc that are easily affected - especially high-impedance signals that are likely to behave like antennas?
How do you know the processor keeps running? Might it possibly restart - but since it runs after restart you still see blinking LED:s etc?
My board has a graphical LCD which its state shows is not being reset also it is very strong against possible noise like an electric valve when under load or AC Main power shutdowns. board shares ground with PC using USB connection of ST-LINK V2. same problem in debug mode happen with MB963C STM32L Discovery board.