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) {
    mode&=(1<<3)-1;
    speed&=(1<<5)-1;
    status&=(1<<6)-1;
    uint16_t reg=~0xFFFF;
    reg|=(mode<<0)|(speed<<3)|(status<<10);
    return reg;


    return 0;
}

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;
}