71. 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);

    // Fill union and print channel and adc_value
    ADC_Result res;
    res.adc_reg = reg;

    uint16_t val = res.adc_value;
    uint16_t ch  = res.channel;

    printf("Channel: %u\nADC Value: %u\n", ch, val);

    return 0;
}