Pack Multiple Fields into a 16-bit Control Register

Code

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

uint16_t pack_register(uint8_t mode, uint8_t speed, uint8_t status) {
    // Your logic here
    uint16_t result ;
     result|=0x07&mode;
     result|=(0x1F&speed)<<3;
     result=result&~(0x3<<8);
     result|=(0x3f&status)<<10;
    return result;
}

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;
}

Solving Approach

create the mask for each field with len 111... and take AND with the value and then apply the value to each field accordingly.