Using serial port:
I used the USB serial converter by seeed
The GND is connected to pin 37, the VCC to pin 65 et the RX to the TX of the board (pin 53). Once the serial interface is connectted to USB of the PC, the board is directly powerd by USB. However you cannot program the STM. For programming you need also to connect the NZ 32-SC151 to the the PC via its micro-USB connector. Using device manager you can find which COM is connected as serial, ans you can also use Hyper terminal or hercules serial to communicate with the PC.