4 Brendan Howell atmega168 2009-01-09 IC DIP Microcontroller Atmel through-hole Atmega168-20PU /obsolte/Microcontroller Atmel AVR DIP28 [THT] Atmel ATmega168 microcontroller. The hardware hacker favorite. PB2 (SS/OC1B/PCINT3)

GND

PB3 (MOSI/OC2A/PCINT3)

PB6 (PCINT6/XTAL1/TOSC1)

PB7 (PCINT7/XTAL2/TOSC2)

PB4 (MISO/PCINT4)

PB5 (SCK/PCINT5)

AVCC

AREF

GND

PC0 (ADC0/PCINT8)

PC1 (ADC1/PCINT9)

PC2 (ADC2/PCINT10)

PC3 (ADC3/PCINT11)

PC4 (ADC4/SDA/PCINT12)

PC5 (ADC5/SCL/PCINT13)

PC6 (PCINT14/RESET)

PD0 (PCINT16/RXD)

PD1 (PCINT17/TXD)

PD5 (PCINT21/OC0B/T1)

PD2 (PCINT18/INT0)

PD6 (PCINT22/OC0A/AIN0)

PD3 (PCINT19/OC2B/INT1)

PD7 (PCINT23/AIN1)

PD4 (PCINT20/XCK/T0)

PB0 (PCINT0/CLK0/ICP1)

VCC

PB1 (OC1A/PCINT1)