| No. | Definition | Function Description |
| 1 | 3.3V | 3.3V Electric pin |
| 2 | 3.3V | 3.3V Electric pin |
| 3 | GND | Floor reference ground |
| 4 | GND | Floor reference ground |
| 5 | 3.3V | 3.3V Electric pin |
| 6 | GND | Floor reference ground |
| 7 | REST | MCU External reset pind |
| 8 | SWIM | SWIM pin of MCU |
| 9 | 3.3V | 3.3V Electric pin |
| 10 | VCC | Module power supply pin, need to be short-circuited with pin 9 to supply power to the module |
| 11 | PC6 | MCU ordinary IO |
| 12 | PC5 | MCU ordinary IO |
| 13 | PB3 | MCU ordinary IO |
| 14 | PB2 | MCU ordinary IO |
| 15 | PB1 | MCU ordinary IO |
| 16 | PB0 | MCU ordinary IO |
| 17 | M1 | Module mode switch pin (see module product manual for details) |
| 18 | M0 | Module mode switch pin (see module product manual for details) |
| 19 | PD1 | MCU ordinary IO |
| 20 | PD0 | MCU ordinary IO |
| 21 | GND | Floor reference ground |
| 22 | GND | Floor reference ground |
| 23 | 5V | 5V Electric pin |
| 24 | 5V | 5V Electric pin |