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Arduino UNO
Arduino UNO R3 (ATmega328P) by Arduino ↗
The classic board for electronics: programmed in C++, 5 V pins for sensors, motors and lights.
2Use it
| Pin or leg | What it is for |
|---|---|
| 5V | 5 V out for sensors and servos |
| GND | 0 V: join it to the GND of every part |
| 2 to 13 | digital pins: on or off; the ones marked ~ (3, 5, 6, 9, 10, 11) can also dim (PWM) |
| A0 to A5 | analog inputs: they read 0 to 1023 |
| 0 and 1 | the USB serial line: keep parts off them |
- Upload with the USB cable; the same cable powers it.
- Every LED needs a resistor, and every part needs its GND on a GND pin.
- A pin gives about 20 mA: motors need a driver, and servos their 5 V from the 5V pin or their own supply.
- Keep pins 0 and 1 free, or uploading may fail.
Good to know: Ours came in the Arduino Education Starter Kit, with a breadboard, parts and wires.
Used in
3Facts
| Logic | 5 V |
|---|---|
| Pins | 14 digital (6 with PWM), 6 analog inputs |
| Power | USB or 7-12 V on the round plug |
| Memory | 32 KB for the program |
Kinds you may find
| UNO WiFi Rev2 | the pins in the same places, with WiFi and a motion sensor |
|---|---|
| Nano | the same kind of chip on a small board that sits in a breadboard |