CPU
CPUCPU Registers
ATmega644 peripherals
Each block of the ATmega644: what it is, the registers that control it and the pins it uses.
PORTA
PORTI/O Port
Registers
PORTB
PORTI/O Port
Registers
PORTC
PORTI/O Port
Registers
PORTD
PORTI/O Port
Registers
EXINT
EXINTExternal Interrupts
Registers
Pins
PCINT0PA0PCINT1PA1PCINT2PA2PCINT3PA3PCINT4PA4PCINT5PA5PCINT6PA6PCINT7PA7PCINT8PB0PCINT9PB1INT2PB2PCINT10PB2PCINT11PB3PCINT12PB4PCINT13PB5PCINT14PB6PCINT15PB7PCINT16PC0PCINT17PC1PCINT18PC2PCINT19PC3PCINT20PC4PCINT21PC5PCINT22PC6PCINT23PC7PCINT24PD0PCINT25PD1INT0PD2PCINT26PD2INT1PD3PCINT2727PD3PCINT2828PD4PCINT2929PD5PCINT3030PD6PCINT3131PD7
TC0
TC8Timer/Counter, 8-bit
Registers
Pins
TC1
TC16Timer/Counter, 16-bit
Registers
Pins
TC2
TC8_ASYNCTimer/Counter, 8-bit Async
Registers
Pins
USART0
USARTUSART
Registers
Pins
SPI
SPISerial Peripheral Interface
Registers
Pins
TWI
TWITwo Wire Serial Interface
Registers
Pins
ADC
ADCAnalog-to-Digital Converter
Registers
Pins
AC
ACAnalog Comparator
Registers
Pins
EEPROM
EEPROMEEPROM
Registers
WDT
WDTWatchdog Timer
Registers
JTAG
JTAGJTAG Interface