adc12_a_ex3_extRef.c

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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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//******************************************************************************
//******************************************************************************
 
#include "driverlib.h"
 
void main (void)
{
    //Stop Watchdog Timer
    WDT_A_hold(WDT_A_BASE);
 
    //Enable A/D channel A0
    GPIO_setAsPeripheralModuleFunctionInputPin(GPIO_PORT_P6,
        GPIO_PIN0
        );
 
    //Initialize the ADC12_A Module
    /*
     * Base address of ADC12_A Module
     * Use internal ADC12_A bit as sample/hold signal to start conversion
     * USE MODOSC 5MHZ Digital Oscillator as clock source
     * Use default clock divider of 1
     */
    ADC12_A_init(ADC12_A_BASE,
        ADC12_A_SAMPLEHOLDSOURCE_SC,
        ADC12_A_CLOCKSOURCE_ADC12OSC,
        ADC12_A_CLOCKDIVIDER_1);
 
   ADC12_A_enable(ADC12_A_BASE);
 
    /*
     * Base address of ADC12_A Module
     * For memory buffers 0-7 sample/hold for 16 clock cycles
     * For memory buffers 8-15 sample/hold for 4 clock cycles (default)
     * Disable Multiple Sampling
     */
    ADC12_A_setupSamplingTimer(ADC12_A_BASE,
        ADC12_A_CYCLEHOLD_16_CYCLES,
        ADC12_A_CYCLEHOLD_4_CYCLES,
        ADC12_A_MULTIPLESAMPLESDISABLE);
 
    //Configure Memory Buffer
    /*
     * Base address of the ADC12_A Module
     * Configure memory buffer 0
     * Map input A0 to memory buffer 0
     * Vref+ = VeREF+ (ext)
     * Vref- = AVss
     * Memory buffer 0 is not the end of a sequence
     */
    ADC12_A_configureMemoryParam param = {0};
    param.memoryBufferControlIndex = ADC12_A_MEMORY_0;
    param.inputSourceSelect = ADC12_A_INPUT_A0;
    param.positiveRefVoltageSourceSelect = ADC12_A_VREFPOS_EXT;
    param.negativeRefVoltageSourceSelect = ADC12_A_VREFNEG_AVSS;
    param.endOfSequence = ADC12_A_NOTENDOFSEQUENCE;
    ADC12_A_configureMemory(ADC12_A_BASE ,&param);
    
    while (1)
    {
        //Enable/Start first sampling and conversion cycle
        /*
         * Base address of ADC12_A Module
         * Start the conversion into memory buffer 0
         * Use the single-channel, single-conversion mode
         */
        ADC12_A_startConversion(ADC12_A_BASE,
            ADC12_A_MEMORY_0,
            ADC12_A_SINGLECHANNEL);
 
        //Poll for interrupt on memory buffer 0
        while (!ADC12_A_getInterruptStatus(ADC12_A_BASE,
                   ADC12IFG0)) ;
 
        //SET BREAKPOINT HERE
        __no_operation();
    }
}