4 register description for i/o-ports, 1 port b data register - portb, 2 port b data direction register - ddrb – Rainbow Electronics ATmega64C1 User Manual

Page 79: 3 port b input pins address - pinb, 4 port c data register - portc, 5 port c data direction register - ddrc, 6 port c input pins address - pinc, 7 port d data register - portd, 8 port d data direction register - ddrd, D in “register description for i/o-ports