| Pin |
Symbol |
Description |
| 1 |
(RESET
) PC6
|
reset (active low); port C |
| 2 |
(RXD) PD0 |
UART receive; port D |
| 3 |
(TXD) PD1 |
UART transmit; port D |
| 4 |
(INT0) PD2 |
external interrupt 0; port D |
| 5 |
(INT1) PD3 |
external interrupt 1; port D |
| 6 |
(XCK/T0) PD4 |
port D |
| 7 |
Vcc |
supply voltage |
| 8 |
GND |
ground |
| 9 |
(XTAL1/TOSC1) PB6 |
clock oscillator pin 1; port B |
| 10 |
(XTAL2/TOSC2) PB7 |
clock oscillator pin 2; port B |
| 11 |
(T1) PD5 |
port D |
| 12 |
(AIN0) PD6 |
port D |
| 13 |
(AIN1) PD7 |
port D |
| 14 |
(ICP1) PB0 |
port B |
| 15 |
PB1 (OC1A) |
port B |
| 16 |
PB2 (SS/OC1B) |
SPI slave select; port B |
| 17 |
PB3 (MOSI/OC2) |
SPI master output/slave input; port B |
| 18 |
PB4 (MISO) |
SPI master input/slave output; port B |
| 19 |
PB5 (SCK) |
SPI master clock; port B |
| 20 |
AVcc |
A/D converter supply voltage |
| 21 |
AREF |
analog reference for A/D converter |
| 22 |
GND |
ground |
| 23 |
PC0 (ADC0) |
port C |
| 24 |
PC1 (ADC1) |
port C |
| 25 |
PC2 (ADC2) |
port C |
| 26 |
PC3 (ADC3) |
port C |
| 27 |
PC4 (ADC4/SCL) |
2-wire clock; port C |
| 28 |
PC5 (ADC5/SDA) |
2-wire data; port C |