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 ENABLE_MASK  (1u  << ENABLE_POS)
#define MODE_MASK    (0x3u << MODE_POS)
#define SPEED_MASK   (0x7u << SPEED_POS)

#define SET_ENABLE(val)   ( ((uint16_t)(val) & 0x1u) << ENABLE_POS )
#define SET_MODE(val)     ( ((uint16_t)(val) & 0x3u) << MODE_POS   )
#define SET_SPEED(val)    ( ((uint16_t)(val) & 0x7u) << SPEED_POS  )

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