MSP432如果主循环不休眠

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/*******************************************************************************
 * MSP432 PCM - Active mode ~1mA current consumption with LDO & DCO.
 *
 * Description: In this very simple example, the device is configured to operate
 * at 4MHz with the LDO on. The example shows 1mA current consumption
 * while using the DCO for MCLK in active mode.
 *
 *                MSP432P4111
 *             ------------------
 *         /|\|                  |
 *          | |                  |
 *          --|RST               |
 *            |                  |
 *            |                  |
 *            |                  |
 *            |                  |
 *
 ******************************************************************************/
/* DriverLib Includes */
#include <ti/devices/msp432p4xx/driverlib/driverlib.h>

/* Standard Includes */
#include <stdint.h>
#include <stdbool.h>

volatile uint32_t mclk = 0;
volatile uint32_t curPowerState;

int main(void)
{
    /* Halting the Watch-dog */
    MAP_WDT_A_holdTimer();

    /* Terminating all remaining pins to minimize power consumption. This is
        done by register accesses for simplicity and to minimize branching API
        calls */
    MAP_GPIO_setAsOutputPin(GPIO_PORT_PA, PIN_ALL16);
    MAP_GPIO_setAsOutputPin(GPIO_PORT_PB, PIN_ALL16);
    MAP_GPIO_setAsOutputPin(GPIO_PORT_PC, PIN_ALL16);
    MAP_GPIO_setAsOutputPin(GPIO_PORT_PD, PIN_ALL16);
    MAP_GPIO_setAsOutputPin(GPIO_PORT_PE, PIN_ALL16);
    MAP_GPIO_setAsOutputPin(GPIO_PORT_PJ, PIN_ALL16);
    MAP_GPIO_setOutputLowOnPin(GPIO_PORT_PA, PIN_ALL16);
    MAP_GPIO_setOutputLowOnPin(GPIO_PORT_PB, PIN_ALL16);
    MAP_GPIO_setOutputLowOnPin(GPIO_PORT_PC, PIN_ALL16);
    MAP_GPIO_setOutputLowOnPin(GPIO_PORT_PD, PIN_ALL16);
    MAP_GPIO_setOutputLowOnPin(GPIO_PORT_PE, PIN_ALL16);
    MAP_GPIO_setOutputLowOnPin(GPIO_PORT_PJ, PIN_ALL16);

    /* Before we set the DCO, transition the device to use LDO */
    MAP_PCM_setPowerState(PCM_AM_LDO_VCORE0);

    /* At 4MHz in VCORE0, MSP432P401R needs 0 wait states */
    MAP_FlashCtl_setWaitState(FLASH_BANK0, 0);
    MAP_FlashCtl_setWaitState(FLASH_BANK1, 0);

    /* Enabling FPU for DCO Frequency calculation */
    MAP_FPU_enableModule();

    /* Set DCO to 4MHz */
    MAP_CS_setDCOFrequency(4000000);

    /* Set MCLK = DCO = 4MHz */
    MAP_CS_initClockSignal(CS_MCLK, CS_DCOCLK_SELECT, CS_CLOCK_DIVIDER_1);

    /* Disabling high side voltage monitor/supervisor */
    MAP_PSS_disableHighSide();

    while (1)
    {
        mclk = MAP_CS_getDCOFrequency();
        curPowerState = MAP_PCM_getPowerState();
        while(1);
    }
}