正如评论中提到的，使用union会容易得多。

#include <stdio.h>
#include <stddef.h>

typedef union {
    uint32_t i;
    uint8_t c[4];
} u_t;

int main( void ) {
    u_t u = { 0 };

    // Little Endian machine
    u.c[0] = 0x19; // I believe these are the hex equivalent of OP data.
    u.c[1] = 0xC9;
    u.c[2] = 0x2A;
    u.c[3] = 0xCE;

    u.i &= 0x1F << (14-1); // Mask for 5 bits, b14-b18

    printf( "%08X\n", u.i );
    printf( "%u\n", u.i );

    printf( "%u\n", u.i >> 8 ); // my (our) mistake

    printf( "%u\n", u.i >> 14 ); // Perhaps what was intended

    return 0;
}

0002C000
180224
704
11

当然，这会简单得多，只需将值向右移位，然后屏蔽最低的5位......这是战争......