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.
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.