1.32.2 Analog Digital Converter (ADC)

Using The Library

ADC Sample:

#include <stddef.h>                     // Defines NULL
#include <stdbool.h>                    // Defines true
#include <stdlib.h>                     // Defines EXIT_FAILURE
#include <stdio.h>
#include "definitions.h"                // SYS function prototypes

#define ADC_VREF                (3.3f)
#define DAC_COUNT_INCREMENT     (170U)  // Equivalent to 0.1V with the given DAC reference 
#define DAC_COUNT_MAX           (4095U)

uint16_t adc_count;
float input_voltage;
/* Initial value of dac count which is midpoint = 1.2 V*/
uint16_t dac_count = 2048;   

void switch_handler(uintptr_t context )
{
    /* Write next data sample */
    dac_count = dac_count + DAC_COUNT_INCREMENT;
    
    if (dac_count > DAC_COUNT_MAX)
            dac_count = 2048;    
    
    DAC_DataWrite(DAC_CHANNEL_0, dac_count);
}

// *****************************************************************************
// *****************************************************************************
// Section: Main Entry Point
// *****************************************************************************
// *****************************************************************************

int main ( void )
{
    /* Initialize all modules */
    SYS_Initialize ( NULL );
    
    printf("\n\r---------------------------------------------------------");
    printf("\n\r                    ADC Sample Demo                 ");
    printf("\n\r---------------------------------------------------------\n\r");
    
    ADC0_Enable();
    SYSTICK_TimerStart();
    EIC_CallbackRegister(EIC_PIN_15, switch_handler, (uintptr_t) NULL);
    DAC_DataWrite(DAC_CHANNEL_0, dac_count);
    while (1)
    {
        /* Start ADC conversion */
        ADC0_ConversionStart();

        /* Wait till ADC conversion result is available */
        while(!ADC0_ConversionStatusGet())
        {

        };

        /* Read the ADC result */
        adc_count = ADC0_ConversionResultGet();
        input_voltage = (float)adc_count * ADC_VREF / 4095U;

        printf("ADC Count = 0x%03x, ADC Input Voltage = %d.%02d V \r", adc_count, (int)input_voltage, (int)((input_voltage - (int)input_voltage)*100.0));
        
        SYSTICK_DelayMs(500);
    }

    /* Execution should not come here during normal operation */

    return ( EXIT_FAILURE );
}

Library Interface

Analog Digital Converter peripheral library provides the following interfaces:

Functions

Data types and constants