Macro-Based Register Config Helper

Code

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

// Define macros here
#define SET_ENABLE(reg,enable) ((reg) |= (enable << 0))
#define SET_MODE(reg,mode) ((reg) |= (mode << 1))
#define SET_SPEED(reg,speed) ((reg) |= (speed << 3))

uint16_t build_register(uint8_t enable, uint8_t mode, uint8_t speed) {
    // Use macros to set fields
    uint16_t reg=0;
    SET_ENABLE(reg,enable);
    SET_MODE(reg,mode);
    SET_SPEED(reg,speed);

    return reg;
}

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