#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/adc.h"

void app_main()
{
    adc1_config_width(ADC_WIDTH_BIT_12);  // Set 12-bit ADC resolution (0–4095)

    // GPIO4 is ADC1 channel 3, input voltage up to ~3.3V
    adc1_config_channel_atten(ADC1_CHANNEL_3, ADC_ATTEN_DB_11); 

    int adc_value_12bit = 0;
    int adc_value_11bit = 0;
    int adc_value_10bit = 0;
    int adc_value_9bit  = 0;
    float voltage = 0;

    while (1) {
        adc_value_12bit = adc1_get_raw(ADC1_CHANNEL_3);   // Read raw 12-bit value
        voltage = adc_value_12bit * 3.3 / 4095;       // Vref = 3.3V

        // Simulate lower resolutions by right shifting
        adc_value_11bit = adc_value_12bit >> 1;     // Divided by 2 for 11 bits
        adc_value_10bit = adc_value_11bit >> 1;// Divided by 4 for 10 bits
        adc_value_9bit = adc_value_10bit >> 1;// Divided by 8 for 9 bits

        printf("ADC 12-bit: %4d | 11-bit: %4d | 10-bit: %4d | 9-bit: %4d | Voltage: %.2f V\n",
               adc_value_12bit, adc_value_11bit, adc_value_10bit, adc_value_9bit, voltage);

        vTaskDelay(pdMS_TO_TICKS(500));              
    }
}