1 #include "stdlib.h"

     2 //#include "switch.h"

     3 

     4 #include <avr/io.h>

     5 #include <avr/interrupt.h>

     6 

     7 byte switch_mask;

     8 byte switch_status;

     9 byte switch_state;

    10 

    11 ISR(PCINT0_vect)

    12 {

    13     switch_status = 1;

    14     switch_state = PINB;

    15 }

    16 

    17 ISR(PCINT1_vect)

    18 {

    19     switch_status = 1;

    20     switch_state = PINC;

    21 }

    22 

    23 ISR(PCINT2_vect)

    24 {

    25     switch_status = 1;

    26     switch_state = PIND;

    27 }

    28 

    29 byte switch_read (byte *sp)

    30 {

    31     if (!switch_status)

    32         return 0;

    33 

    34     switch_status = 0;

    35 

    36     *sp = ~switch_state & switch_mask;

    37 

    38     return 1;

    39 }