Macro-Based Register Config Helper

#include <stdio.h>
#include <stdint.h>
/*
#define ENABLE_POS  0
#define MODE_POS    1
#define SPEED_POS   3
*/
#define SET_ENABLE(val)  (((uint16_t)(val) & 0x01) << 0)

// MODE: 2 bits at position 1
#define SET_MODE(val)    (((uint16_t)(val) & 0x03) << 1)

// SPEED: 3 bits at position 3
#define SET_SPEED(val)   (((uint16_t)(val) & 0x07) << 3)

uint16_t build_register(uint8_t enable, uint8_t mode, uint8_t speed) {
    uint16_t reg = 0;

    // Combine the fields using the macros
    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;
}