Macro-Based Register Config Helper

Code

#include <stdio.h>
#include <stdint.h>
#define ENABLE(x,y)     ((x)|(y<<0))
#define MODE(x,y)       ((x)|(y<<1))
#define SPEED(x,y)      ((x)|(y<<3))
#define RESERVED(x)    ((x)&(0xff3f))
// Define macros here

uint16_t build_register(uint8_t enable, uint8_t mode, uint8_t speed) {
    // Use macros to set fields
    uint16_t reg=0;
    return RESERVED(SPEED(MODE(ENABLE(reg,enable),mode),speed));
}

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

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

Solving Approach