Macro-Based Register Config Helper

Code

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

// Define macros here
#define ENABLE_POS  0
#define MODE_POS    1
#define SPEED_POS   3

#define SET_ENABLE(x) ((x & 1) << ENABLE_POS)
#define SET_MODE(x) ((x & 3) << MODE_POS)
#define SET_SPEED(x) ((x & 7) << SPEED_POS)

uint16_t build_register(uint8_t enable, uint8_t mode, uint8_t speed) {
    // Use macros to set fields
    return (SET_ENABLE(enable) | SET_MODE(mode) | SET_SPEED(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