Macro-Based Register Config Helper

Code

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

// Define macros here
#define ENABLE(enable)  (enable<<0)     // left shift the enable bit at 0 Position.
#define Mode(mode)      (mode<<1)       // left shift the mode bit at 1st Position.
#define SPEED(speed)    (speed<<3)      // left shift the speed bit at 3rd Position.

uint16_t build_register(uint8_t enable, uint8_t mode, uint8_t speed) {
    // Use macros to set fields
    uint16_t reg = 0;                   // intialize the reg variable with zero
    
    /* Do Or(|) operation with reg and all macros. */
    reg |= ENABLE(enable) | Mode(mode) | 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

// Define macros here

#define ENABLE(enable)  (enable<<0)     // left shift the enable bit at 0 Position.

#define Mode(mode)      (mode<<1)       // left shift the mode bit at 1st Position.

#define SPEED(speed)    (speed<<3)      // left shift the speed bit at 3rd Position.

uint16_t build_register(uint8_t enable, uint8_t mode, uint8_t speed) {

    // Use macros to set fields

    uint16_t reg = 0;                   // intialize the reg variable with zero

    /* Do Or(|) operation with reg and all macros. */

    reg |= ENABLE(enable) | Mode(mode) | SPEED(speed) ;

    return reg;

}