timepacked32bit.c

#include <stdio.h>
#include <string.h>
#include <stdint.h>
/*

Time  interface:

Witdh : 32 bits

Bit Range   Name    Desciription
0 - 4       Day     00001(1d) min
                    11111(31d) max

5 - 8       Mounth  0001(1d) min
                    1101(12d) max

9 - 14      Year    111111(63) max

15 - 19     Hour    MSB bit for AM or PM 11101(12d) max

20 - 25     Minute  111111(63d) max

26 - 31     Second  111111(63d) max

*/

static uint32_t marshall_time ( unsigned int d, 
                                unsigned int m, 
                                unsigned int y, 
                                unsigned int h, 
                                unsigned int am_or_pm, 
                                unsigned int mi, 
                                unsigned int s )
{
    uint32_t ret_time = 0; 

    ret_time |= (d);
    ret_time |= (m << 5);
    ret_time |= (y << 9);
    ret_time |= (h << 15);
    ret_time |= (am_or_pm << 19);
    ret_time |= (mi << 20);
    ret_time |= (s << 26);

    return ret_time;
}

static uint32_t unmarshall_time (uint32_t time)
{
    unsigned int d, m, y, h, min, s = 0;

    d = time & (31);
    m = (time & (15 << 5)) >> 5;
    y = (time & (63 << 9)) >> 9;
    h = (time & (15 << 15)) >> 15;
    int am_or_pm = (time & (1 << 19)) >> 19;
    min = (time & (63 << 20)) >> 20;
    s = (time & (63 << 26)) >> 26;


    printf("\r\n D : %u", d);
    printf("\r\n M : %u", m);
    printf("\r\n Y : %u", y);
    printf("\r\n H : %u", h);
    printf("\r\n am_or_pm %u", am_or_pm);
    printf("\r\n Mi : %u", min);
    printf("\r\n S : %u", s);
}

int main(int argc, char* argv[])
{
    uint32_t ret_time = marshall_time(5, 4, 21, 9, 1, 32, 53);    

    unmarshall_time(ret_time);
}