Macro-Based Register Config Helper

Code

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

// Define macros here
#define ENABLE(e) ((e & 0x01)<< 0)
#define MODE(m) ((m & 0x03) <<1U)
#define SPEED(s) ((s & 0x07) <<3U)
uint16_t build_register(uint8_t enable, uint8_t mode, uint8_t speed) {
    // Use macros to set fields
    uint32_t reg = 0;
    reg |= SPEED(speed);
    reg |= MODE(mode);
    reg |= ENABLE(enable);
    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