Clock:
32Mhz HSE (high speed passive crystal oscillator)
32.768Khz LSE (low speed passive crystal oscillator)
Power:
3.3V-5V power input, 3.3V LDO maximum 100mA additional output.
USB power supply with diode series to prevent current backflow.
At the same time, the diode can be bypassed by a short circuit pad.
5V with TVS diode.
Interfaces:
12Pin I/O interface with a 2.54mm spacing * 2
Keys:
Reset/B23 button * 1
Boot/ B22 button * 1