comp_b_ex4_hysteresis.c

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//******************************************************************************
//******************************************************************************
#include "driverlib.h"
 
void main (void)
{
    //Stop WDT
    WDT_A_hold(WDT_A_BASE);
 
    //Select CBOUT function on P1.6/CBOUT and set P1.6 output direction
    GPIO_setAsPeripheralModuleFunctionOutputPin(
        GPIO_PORT_P1,
        GPIO_PIN6);
    //Initialize the Comparator B module
    /*
     * Base Address of Comparator B,
     * Pin CB0 to Positive(+) Terminal,
     * Reference Voltage to Negative(-) Terminal,
     * Ultra-Low Power Mode,
     * Output Filter On with minimal delay,
     * Non-Inverted Output Polarity
     */
    Comp_B_initParam initParam = {0};
    initParam.positiveTerminalInput = COMP_B_INPUT0;
    initParam.negativeTerminalInput = COMP_B_VREF;
    initParam.powerModeSelect = COMP_B_POWERMODE_NORMALMODE;
    initParam.outputFilterEnableAndDelayLevel = COMP_B_FILTEROUTPUT_DLYLVL1;
    initParam.invertedOutputPolarity = COMP_B_NORMALOUTPUTPOLARITY;
    Comp_B_init(COMP_B_BASE, &initParam);
 
    //Set the reference voltage that is being supplied to the (-) terminal
    /*
     * Base Address of Comparator B,
     * Reference Voltage of Vcc,
     * Lower Limit of Vcc*(8/32) = (1/4)*Vcc,
     * Upper Limit of Vcc*(24/32) = (3/4)*Vcc,
     * Static Mode Accuracy
     */
    Comp_B_configureReferenceVoltageParam refVoltageParam = {0};
    refVoltageParam.supplyVoltageReferenceBase = COMP_B_VREFBASE_VCC;
    refVoltageParam.lowerLimitSupplyVoltageFractionOf32 = 8;
    refVoltageParam.upperLimitSupplyVoltageFractionOf32 = 24;
    refVoltageParam.referenceAccuracy = COMP_B_ACCURACY_STATIC;
    Comp_B_configureReferenceVoltage(COMP_B_BASE, &refVoltageParam);
 
    //Allow power to Comparator module
    Comp_B_enable(COMP_B_BASE);
 
    //delay for the reference to settle
    __delay_cycles(75);
 
    //Enter LPM4
    __bis_SR_register(LPM4_bits);
 
    //For debug
    __no_operation();
}