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

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

// #define status_pos  0
// #define MODE_POS    1
// #define SPEED_POS   3

// #define status_MASK  (1<< status_pos)
// #define MODE_MASK    (0x3U << MODE_POS)
// #define SPEED_MASK   (0x7U << SPEED_POS)




uint16_t pack_register(uint8_t mode, uint8_t speed, uint8_t status) {

    uint16_t reg = 0;
   reg |= (mode & 0x07);           
    reg |= (speed & 0x1F) << 3;     
    
    reg |= (status & 0x3F) << 10;
    return  reg;  
}

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;
}