comp_e_ex1_outputToggleVcompVsVref2V.c

Go to the documentation of this file.

/* --COPYRIGHT--,BSD
 * Copyright (c) 2017, Texas Instruments Incorporated
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * *  Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * *  Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * *  Neither the name of Texas Instruments Incorporated nor the names of
 *    its contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * --/COPYRIGHT--*/
//******************************************************************************
// MSP430FR59xx Demo - COMPE Toggle from LPM4; input channel C2;
//      Vcompare is compared against the internal reference 2.0V
//
// Description: Use CompE (input channel C2) and internal reference to
//    determine if input'Vcompare'is high or low.  When Vcompare exceeds 2.0V
//    COUT goes high and when Vcompare is less than 2.0V then COUT goes low.
//    P3.5/COUT is connected internally to an LED; it will toggle accordingly.
//
//                 MSP430FR5969
//             ------------------
//         /|\|                  |
//          | |                  |
//          --|RST        P1.2/C2|<--Vcompare
//            |                  |
//            |         P3.5/COUT|----> 'high'(Vcompare>2.0V); 'low'(Vcompare<2.0V)
//            |                  |  |
//            |                  |  | LED 'ON'(Vcompare>2.0V); 'OFF'(Vcompare<2.0V)
//            |                  |
//
 
//******************************************************************************
 
#include "driverlib.h"
 
void main(void)
{
    //Stop WDT
    WDT_A_hold(WDT_A_BASE);
 
    //Set P3.5 as Ternary Module Function Output.
    /*
 
    * Select Port 3
    * Set Pin 5 to output Ternary Module Function, (COUT).
    */
    GPIO_setAsPeripheralModuleFunctionOutputPin(
        GPIO_PORT_P3,
        GPIO_PIN5,
        GPIO_TERNARY_MODULE_FUNCTION
    );
 
    /*
     * Disable the GPIO power-on default high-impedance mode to activate
     * previously configured port settings
     */
    PMM_unlockLPM5();
 
    //Initialize the Comparator E module
    /* Base Address of Comparator E,
    * Pin CE2 to Positive(+) Terminal,
    * Reference Voltage to Negative(-) Terminal,
    * Normal Power Mode,
    * Output Filter On with minimal delay,
    * Non-Inverted Output Polarity
    */
      
    Comp_E_initParam param = {0};
    param.posTerminalInput = COMP_E_INPUT2;
    param.negTerminalInput = COMP_E_VREF;
    param.outputFilterEnableAndDelayLevel = COMP_E_FILTEROUTPUT_OFF;
    param.invertedOutputPolarity = COMP_E_NORMALOUTPUTPOLARITY;
    Comp_E_init(COMP_E_BASE, &param);
 
    //Set the reference voltage that is being supplied to the (-) terminal
    /* Base Address of Comparator E,
    * Reference Voltage of 2.0 V,
    * Lower Limit of 2.0*(32/32) = 2.0V,
    * Upper Limit of 2.0*(32/32) = 2.0V
    */
    Comp_E_setReferenceVoltage(COMP_E_BASE,
      COMP_E_VREFBASE2_0V,
      32,
      32
      );
 
    //Disable Input Buffer on P1.2/CE2
    /* Base Address of Comparator E,
     * Input Buffer port
     * Selecting the CEx input pin to the comparator
     * multiplexer with the CEx bits automatically
     * disables output driver and input buffer for
     * that pin, regardless of the state of the
     * associated CEPD.x bit
     */
      Comp_E_disableInputBuffer(COMP_E_BASE,
          COMP_E_INPUT2);
 
    //Allow power to Comparator module
    Comp_E_enable(COMP_E_BASE);
 
    __delay_cycles(400);           // delay for the reference to settle
 
    __bis_SR_register(LPM4_bits);          // Enter LPM4
    __no_operation();                      // For debug
}