timer_b_ex3_pwm.c

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//******************************************************************************
//   Timer_B, PWM TB1-6, Up Mode, DCO SMCLK
//
//   Description: This program generates two PWM outputs on P1.4/P1.5 using
//   Timer_B configured for up mode. The value in CCR0, 512-1, defines the PWM
//   period and the values in CCR1-2 the PWM duty cycles. Using ~1048kHz SMCLK
//   as TBCLK, the timer period is ~488us.
//   ACLK = 32kHz, SMCLK = MCLK = TBCLK = default DCO ~1048kHz.
//
//   Tested On: MSP430FR5739
//             -----------------
//         /|\|              XIN|-
//          | |                 |  32kHz
//          --|RST          XOUT|-
//            |                 |
//            |       P1.4/TB0.1|--> CCR1 - 75% PWM
//            |       P1.5/TB0.2|--> CCR2 - 25% PWM
//            |                 |
//            |                 |
//            |                 |
//            |                 |
//
//******************************************************************************
 
#include "driverlib.h"
 
void main(void)
{
    //Stop WDT
    WDT_A_hold(WDT_A_BASE);
 
    GPIO_setAsPeripheralModuleFunctionOutputPin(
        GPIO_PORT_P1,
        GPIO_PIN4 | GPIO_PIN5,
        GPIO_PRIMARY_MODULE_FUNCTION
        );
 
    //Start timer
    Timer_B_initUpModeParam initUpParam = {0};
    initUpParam.clockSource = TIMER_B_CLOCKSOURCE_SMCLK;
    initUpParam.clockSourceDivider = TIMER_B_CLOCKSOURCE_DIVIDER_1;
    initUpParam.timerPeriod = 511;
    initUpParam.timerInterruptEnable_TBIE = TIMER_B_TBIE_INTERRUPT_DISABLE;
    initUpParam.captureCompareInterruptEnable_CCR0_CCIE =
        TIMER_B_CCIE_CCR0_INTERRUPT_DISABLE;
    initUpParam.timerClear = TIMER_B_DO_CLEAR;
    initUpParam.startTimer = false;
    Timer_B_initUpMode(TIMER_B0_BASE, &initUpParam);
 
    Timer_B_startCounter(TIMER_B0_BASE,
        TIMER_B_UP_MODE
        );
 
    //Initialize compare mode to generate PWM1
    Timer_B_initCompareModeParam initComp1Param = {0};
    initComp1Param.compareRegister = TIMER_B_CAPTURECOMPARE_REGISTER_1;
    initComp1Param.compareInterruptEnable = TIMER_B_CAPTURECOMPARE_INTERRUPT_DISABLE;
    initComp1Param.compareOutputMode = TIMER_B_OUTPUTMODE_RESET_SET;
    initComp1Param.compareValue = 383;
    Timer_B_initCompareMode(TIMER_B0_BASE, &initComp1Param);
 
    //Initialize compare mode to generate PWM2
    Timer_B_initCompareModeParam initComp2Param = {0};
    initComp2Param.compareRegister = TIMER_B_CAPTURECOMPARE_REGISTER_2;
    initComp2Param.compareInterruptEnable = TIMER_B_CAPTURECOMPARE_INTERRUPT_ENABLE;
    initComp2Param.compareOutputMode = TIMER_B_OUTPUTMODE_RESET_SET;
    initComp2Param.compareValue = 128;
    Timer_B_initCompareMode(TIMER_B0_BASE, &initComp2Param);
 
    _BIS_SR(LPM0_bits + GIE);                 // CPU off
}