7. AVR Pin Assignment Table Sorted by Function

 Function   Pin 
digital I/Os (x16) PB0, PB1, PB2, PB4, PB5,
PC0, PC1, PC2, PC3, PC4, PC5,
PD0, PD1, PD2, PD4, PD7
analog inputs (x8) PC0, PC1, PC2, PC3, PC4, PC5, ADC6, ADC7
motor 1 control (A and B) PD5 and PD6
motor 2 control (A and B) PD3 and PB3
red user LED PD1
user trimmer potentiometer ADC7
ISP programming lines (x3) PB3, PB4, PB5
UART (RX and TX) PD0 and PD1
I2C/TWI (SDA and SCL) PC4 and PC5
SPI inaccessable to user
Timer1 PWM outputs (A and B) PB1 and PB2