/* Unused pins set as input pull up*/ DDRB &= 0xE0; DDRC &= 0xC9; DDRD &= 0x03; DDRE &= 0xF3; PORTB |= ~(0xE0); PORTC |= ~(0xC9); PORTD |= ~(0x03); PORTE |= ~(0xF3);