/***************************************************
** ADC Example for Making Embedded Systems course **
** This example is lifted from the RPi Pico SDK Examples
** page: https://raspberrypi.github.io/pico-sdk-doxygen/group__hardware__adc.html#adc_example
** 
****************************************************/
#include <stdio.h>
#include "pico/stdlib.h"
#include "hardware/gpio.h"
#include "hardware/adc.h"
 
int main() {
    stdio_init_all();
    printf("ADC Example, measuring GPIO26\n");
 
    adc_init();
 
    // Make sure GPIO is high-impedance, no pullups etc
    adc_gpio_init(26);
    // Select ADC input 0 (GPIO26)
    adc_select_input(0);
 
    while (1) {
        // 12-bit conversion, assume max value == ADC_VREF == 3.3 V
        const float conversion_factor = 3.3f / (1 << 12);
        uint16_t result = adc_read();
        printf("Raw value: 0x%03x, voltage: %f V\n", result, result * conversion_factor);
        sleep_ms(500);
    }
}