#define F_CPU 16000000 // run CPU at 16 MHz #define LED 5 // Boarduino LED on PB5 #define ClearBit(x,y) x &= ~_BV(y) // equivalent to cbi(x,y) #define SetBit(x,y) x |= _BV(y) // equivalent to sbi(x,y)

16 IO with cpu and addon card schematic