25. Pack Multiple Fields into a 16-bit Control Register

#include <stdio.h>
#include <stdint.h>

uint16_t pack_register(uint8_t mode, uint8_t speed, uint8_t status) {
    // Your logic here
    uint16_t res;

    // update value
    res |= (mode& 0xf)<< 0;   // set  mode  for reg
    res |= (speed&0xff)<<3;
    res &= ~(0xf << 8);
    res |= (status&0xff)<<10;

    // extract value ;
    return res;
}

int main() {
    uint8_t mode, speed, status;
    scanf("%hhu %hhu %hhu", &mode, &speed, &status);

    uint16_t reg = pack_register(mode, speed, status);
    printf("%u", reg);
    return 0;
}