Decode ADC Result Using Union Bitfields

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

typedef union {
    struct {
        uint16_t adc_value : 12;
        uint16_t channel   : 4;
    };
    uint16_t adc_reg;
} ADC_Result;

int main() {
    uint16_t reg;
    scanf("%hx", &reg);

    ADC_Result ADC;
    // uint16_t maskadc = ((1U) << 13) - 1; 
    // uint16_t maskchannel = 0xF000;
    // ADC.adc_value = reg & maskadc;
    // ADC.channel = (reg & maskchannel) >> 12;
    ADC.adc_reg = reg;

    printf("Channel: %d\n",ADC.channel);
    printf("ADC Value: %d\n",ADC.adc_value);

    // Fill union and print channel and adc_value
    return 0;
}