关于MSP432模拟量输入

看着没啥问题，附上差分的例程

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/*******************************************************************************
 * MSP432 ADC14 -  Differential Mode with 2's Compliment
 *
 * Description: This example will use the ADC14 module mode in differential
 * mode and take advantage of the 2's compliment mode. One ADC memory location
 * is set to sample the differential voltage between terminals A0 and A1. The
 * sample timer is used to periodically sample the difference in the value,
 * the value is converted is float, and the value is stored in memory for the
 * user to observe in the debugger.
 *
 *                MSP432P4111
 *             ------------------
 *         /|\|                  |
 *          | |                  |
 *          --|RST         P5.5  |<----- A0 In
 *            |            P5.4  |<----- A1 In
 *            |                  |
 *            |                  |
 *
 ******************************************************************************/
/* DriverLib Includes */
#include <ti/devices/msp432p4xx/driverlib/driverlib.h>

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

#include <string.h>

/* Statics */
static volatile float adcResult;
static float convertToFloat(uint16_t result);

int main(void)
{
    /* Halting WDT */
    MAP_WDT_A_holdTimer();
    MAP_Interrupt_enableSleepOnIsrExit();

    /* Enabling the FPU with stacking enabled (for use within ISR) */
    MAP_FPU_enableModule();
    MAP_FPU_enableLazyStacking();

    /* Initializing ADC (MCLK/1/1) */
    MAP_ADC14_enableModule();
    MAP_ADC14_initModule(ADC_CLOCKSOURCE_MCLK, ADC_PREDIVIDER_1, ADC_DIVIDER_1,
            0);

    /* Configuring ADC Memory (ADC_MEM0 A0/A1 Differential) in repeat mode */
    MAP_ADC14_configureSingleSampleMode(ADC_MEM0, true);
    MAP_ADC14_configureConversionMemory(ADC_MEM0, ADC_VREFPOS_AVCC_VREFNEG_VSS,
            ADC_INPUT_A0, true);

    /* Setting up GPIO pins as analog inputs */
    MAP_GPIO_setAsPeripheralModuleFunctionInputPin(GPIO_PORT_P5,
            GPIO_PIN5 | GPIO_PIN4, GPIO_TERTIARY_MODULE_FUNCTION);

    /* Switching data mode to 2's Complement mode */
    MAP_ADC14_setResultFormat(ADC_SIGNED_BINARY);

    /* Enabling sample timer in auto iteration mode and interrupts*/
    MAP_ADC14_enableSampleTimer(ADC_AUTOMATIC_ITERATION);
    MAP_ADC14_enableInterrupt(ADC_INT0);

    /* Enabling Interrupts */
    MAP_Interrupt_enableInterrupt(INT_ADC14);
    MAP_Interrupt_enableMaster();

    /* Triggering the start of the sample */
    MAP_ADC14_enableConversion();
    MAP_ADC14_toggleConversionTrigger();

    /* Going to sleep */
    while (1)
    {
        MAP_PCM_gotoLPM0();
    }
}

/* This interrupt happens every time a conversion has completed. Since the FPU
 * is enabled in stacking mode, we are able to use the FPU safely to perform
 * efficient floating point arithmetic.*/
void ADC14_IRQHandler(void)
{
    uint64_t status;

    status = MAP_ADC14_getEnabledInterruptStatus();
    MAP_ADC14_clearInterruptFlag(status);

    if(status & ADC_INT0)
    {
        adcResult = convertToFloat(MAP_ADC14_getResult(ADC_MEM0));
    }

}

//![Conversion to Real Value]
/* Converts the ADC result (14-bit) to a float with respect to a 3.3v reference
 */
static float convertToFloat(uint16_t result)
{
    int32_t temp;

        if(0x8000 & result)
        {
            temp = (result >> 2) | 0xFFFFC000;
            return ((temp * 3.3f) / 8191);
        }
        else
            return ((result >> 2)*3.3f) / 8191;
}
//![Conversion to Real Value]