Arduino Uno

Arduino Uno (R3) Front View
Processor: ATmega328 (8-bit, 16MHz, 2KB RAM, 32KB Flash)
Features: 14 digital I/O pins, 6 analog input pins
POWER header:
Name | Function |
- | Not connected |
IOREF | Logic Reference (5V) (*) |
RESET | PCINT14/RESET pin |
3.3V | 3.3V |
5V | 5V |
GND | Ground |
GND |
Vin | Input voltage (External power) |
ANALOG header:
Name | MCU pin | Function |
14 (A0) | PC0 (23) | ADC0/PCINT8 |
15 (A1) | PC1 (24) | ADC1/PCINT9 |
16 (A2) | PC2 (25) | ADC2/PCINT10 |
17 (A3) | PC3 (26) | ADC3/PCINT11 |
18 (A4) | PC4 (27) | ADC4/SDA/PCINT12 |
19 (A5) | PC5 (28) | ADC5/SCL/PCINT13 |
DIGITAL header:
Name | MCU pin | Function |
0 | PD0 (2) | PCINT16/RXD |
1 | PD1 (3) | PCINT17/TXD |
2 | PD2 (4) | PCINT18/INT0 |
3 | PD3 (5) | PCINT19/OC2B/INT1 (PWM) |
4 | PD4 (6) | PCINT20/XCK/T0 |
5 | PD5 (11) | PCINT21/OC0B/T1 (PWM) |
6 | PD6 (12) | PCINT22/OC0A/AIN0 (PWM) |
7 | PD7 (13) | PCINT23/AIN1 |
8 | PB0 (14) | PCINT0/CLKO/ICP1 |
9 | PB1 (15) | OC1A/PCINT1 (PWM) |
10 | PB2 (16) | SS/OC1B/PCINT2 (PWM) |
11 | PB3 (17) | MOSI/OC2A/PCINT3 (PWM) |
12 | PB4 (18) | MISO/PCINT4 |
13 | PB5 (19) | SCK/PCINT5 (LED) |
GND | Ground |
AREF | AREF (21) | Analog Ref. |
18 (A4) | PC4 (27) | ADC4/SDA/PCINT12 (*) |
19 (A5) | PC5 (28) | ADC5/SCL/PCINT13 (*) |
ICSP header:
Name | MCU pin | Function |
1 | PB4 (18) | MISO/PCINT4 |
2 | VCC (5 V) |
3 | PB5 (19) | SCK/PCINT5 |
4 | PB3 (17) | MOSI/OC2A/PCINT3 |
5 | PC6 (1) | RESET/PCINT14 |
6 | Ground |
ICSP header (USB interface):
Name | Function |
1 | MISO2 |
2 | VCC (5 V) |
3 | SCK2 |
4 | MOSI2 |
5 | RESET |
6 | Ground |
Notes:
(*) pins available only on Rev.3
OCxA/OCxB can be used for PWM output.
Absolute max current per pin is 40 mA (20 mA recommended).
Absolute max current for the entire package is 200 mA.