Macro-Based Register Config Helper

Code

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

// Define macros here
#define  ENABLE(val)  ((val & 0x01)<<0)
#define  MODE(val)    ( (val&0x03)<<1)
#define  SPEED(val)   ((val&0x07)<<3)

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

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