Find a description how to modify a Discovery Board to use it's Stlink as black magic debug at http://embdev.net/articles/STM_Discovery_as_Black_Magic_Probe Differences between V1/V2 V1 V2 ID Pins PC13/14 unconnected PC 13 pulled low LED STLINK PA8, active High PA9, Dual Led MCO Out NA PA8 RESET(Target) T_JRST(PB1) NRST (PB0) On the NucleoXXXP boards, e.g. NUCLEO-L4R5ZI (144 pin) or NUCLEO-L452RE-P (64 pins), by default nRst is not connected. To reach the target nRST pin with the "mon connect_srst enable" option, the right NRST jumper must be placed. On Nucleo144-P boards it is JP3, on NUCLEO64-P boards it is JP4.