Arduino Uno R3
The Arduino Uno R3 is an older design that doesn’t offer many IO pins and has a large size. Unless you already own one, we recommend purchasing a different board, either the Mega 2560 Pro Mini if you need more IO pins (up to 70) or the Arduino Nano if space is at a premium.
Specifications
- 14 digital IO pins, 6 with PWM support.
- 6 analog inputs (can be used as digital inputs).
| Device | Limit | Notes |
|---|---|---|
| Analog input | 6 | |
| Button | 18 | |
| Digital Input Multiplexer | 6 | |
| Encoder | 9 | |
| Input shift register | 6 | Six chains of shift registers, 32 bits each (2x16 or 4x8 bit shift registers). |
| LCD Display | 2 | |
| LED / Output | 18 | |
| LED 7-Segment | 6 | 6 TM1637 modules, or 6 chains of MAX7219 modules, or a mix of both. A 5V power supply is required when connecting more than one display. |
| Output shift register | 6 | Six chains of shift registers, 32 bits each (2x16 or 4x8 bit shift registers). |
| Servo | 8 | |
| Stepper | 4 |
Pinout
Note
Pins D0 and D1 are not available for use, as they are reserved for USB serial communication.