pmm_Reset_LPMx_5.c

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//******************************************************************************
// This example shows transitions between a user Reset via the reset button, a
// software triggered BOR, and entrance into LPM3.5.
// Reading the reset interrupt flag from PMMIFG register is equivalent
// to reading from reset vector register.
//*******************************************************************************
//
//  1) Power on device:
//     LED1 and LED2 off: device is running and was not in LPM3.5 mode previously.
//
//  2) Press User Reset button:
//
//     LED1 turns on, device is running and has reset due to RST pin
//     LED2 toggles on/off: device has reset due to a software BOR
//     LED1 and LED2 on: device is now in LPM3.5
//
//
//********************************************************************************
#include "driverlib.h"
#include "Board.h"
 
void main(void)
{
    //Stop watchdog timer
    WDT_A_hold(WDT_A_BASE);
 
    /*
    * By default, the pins are unlocked unless waking
    * up from an LPMx.5 state in which case all GPIO
    * are previously locked.
    *
    */
    PMM_unlockLPM5();
    //Set LED1 as output pins.
    GPIO_setAsOutputPin(
        GPIO_PORT_LED1,
        GPIO_PIN_LED1
    );
    //Set LED2 as output pins.
    GPIO_setAsOutputPin(
        GPIO_PORT_LED2,
        GPIO_PIN_LED2
    );
 
    //Was this reset triggered by the Reset flag?
    if (PMM_getInterruptStatus(PMM_RST_INTERRUPT))
    {
        //Clear reset flag
        PMM_clearInterrupt(PMM_RST_INTERRUPT);
        GPIO_setOutputHighOnPin(
            GPIO_PORT_LED1,
            GPIO_PIN_LED1
        );
        //Create a visual delay
        __delay_cycles(1000000);
 
        //Trigger a software Brown Out Reset (BOR)
        /*
        * Base Address of PMM,
        * Forces the devices to perform a BOR.
        */
        //Software trigger a BOR.
        PMM_trigBOR();
    }
 
    //Was this reset triggered by the BOR flag?
    if (PMM_getInterruptStatus(PMM_BOR_INTERRUPT))
    {
        //Clear BOR flag
        PMM_clearInterrupt(PMM_BOR_INTERRUPT);
        GPIO_toggleOutputOnPin(
            GPIO_PORT_LED2,
            GPIO_PIN_LED2
        );
        //Create a visual delay
        __delay_cycles(1000000);
        GPIO_toggleOutputOnPin(
            GPIO_PORT_LED2,
            GPIO_PIN_LED2
        );
 
        //Disable Regulator
        /*
         * Base Address of PMM,
         * Regulator is turned off when going to LPM3/4.
         * System enters LPM3.5 or LPM4.5, respectively.
         */
        PMM_turnOffRegulator();
        // Enter LPM3.5
        __bis_SR_register(LPM3_bits);
    }
 
    while (1)
    {
        // Don't sleep
        __no_operation();
    }
}