typedef enum { wait_rising, wait_falling, ready } Tdat_state;

typedef struct
{
    u8 volatile *in_reg0;
    u8 pin0;
    u8 volatile *in_reg1;
    u8 pin1;
    Tdat_state state;
    u16 time;
} Tgpio_cfg;

#define NUM_DAT 20

Tgpio_cfg dat[ NUM_DAT ];

dat[ 0 ].in_reg0 = PINA;
dat[ 0 ].pin0    = (1 << PA3);
dat[ 0 ].in_reg1 = PINB;
dat[ 0 ].pin1    = (1 << PB6);
dat[ 0 ].state   = wait_rising;

void timer_1ms_func( void )
{
    for( u8 i = 0; i < NUM_DAT; i++  )
    {
        switch( dat[ i ].state )
        {
        case wait_rising:
            if( dat[ i ].in_reg0 & dat[ i ].bit0 )
            {
                dat[ i ].time = 0;
                dat[ i ].state = wait_falling;
            }
            break;

        case wait_falling:
            dat[ i ].time++;
            if( dat[ i ].in_reg1 & dat[ i ].bit1 )
            {
                dat[ i ].state = ready;
            }
            break;
        }
    }
}