Unable to debug with ST-LinkV2-1
There is one more thing I found out. When you connect the board, check in the device manager, if the connected board
is listed under "Universal Serial Bus Devices->STM32 STLink".
Some older boards, e.g. I have tried old STM32F100B - MB913C, are not listed as STLink device, only as a MSD drive,
so it seems to me this could be a problem, why debugging does not work.
There is also difference, if you connect such board with STLink Utility. It will show something like
ST-LINK SN : ST-Link/V1_on_:
ST-LINK Firmware version : V1J13S0
Connected via SWD.
In the working case it shows:
ST-LINK SN :
ST-LINK Firmware version : V2J25S0
Connected via SWD.