Table 1.
Circuit pin connections.
| Arduino Nano (U1) | GY-906 (U2) | OLED (U3) | IR sensor (U4) | TP4056 (U5) | Battery Holder (U6) | Step-up 5 V (U7) | Switch (SW1) | GREEN LED (LED1) | RED LED (LED2) | Buzzer (AB1) |
|---|---|---|---|---|---|---|---|---|---|---|
| Vin | Vin | VCC | – | – | – | – | 1 | – | – | – |
| GND1 | – | – | GND | GND | – | – | – | Cathode | Cathode | Cathode |
| GND2 | GND | GND | – | – | – | Vout- | – | – | – | – |
| A5 | SCL | SCK | – | – | – | – | – | – | – | – |
| A4 | SDA | SDA | – | – | – | – | – | – | – | – |
| D3 | – | – | – | – | – | – | – | Anode | – | – |
| D5 | – | – | – | – | – | – | – | – | Anode | – |
| D7 | – | – | – | – | – | – | – | – | – | Anode |
| D9 | – | – | OUT | – | – | – | – | – | – | – |
| 3 V3 | – | – | VCC | – | – | – | – | – | – | – |
| – | – | – | – | BATT+ | Possitive | – | – | – | – | – |
| – | – | – | – | BATT- | Negative | – | – | – | – | – |
| – | – | – | – | OUT+ | – | Vin+ | – | – | – | – |
| – | – | – | – | OUT- | – | Vin− | – | – | – | – |
| – | – | – | – | – | – | Vout+ | 2 | – | – | – |