Macro-Based Register Config Helper

Code

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

// Define macros here
#define ENABLE_SHIFT    0
#define MODE_SHIFT      1
#define SPEED_SHIFT     3

#define ENABLE_MASK     0x1
#define MODE_MASK       0x3
#define SPEED_MASK      0x7

#define SET_ENABLE(val)   ( ((val) & ENABLE_MASK) << ENABLE_SHIFT )
#define SET_MODE(val)     ( ((val) & MODE_MASK)   << MODE_SHIFT )
#define SET_SPEED(val)    ( ((val) & SPEED_MASK)  << SPEED_SHIFT )

uint16_t build_register(uint8_t enable, uint8_t mode, uint8_t speed) {
    uint16_t result = 0;
    result |= SET_ENABLE(enable);
    result |= SET_MODE(mode);
    result |= SET_SPEED(speed);
    
    return result;
}

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