ACMP的一般应用方法

/******************************************************************************

 * [url=home.php?mod=space&uid=288409]@file[/url]     main.c

 * [url=home.php?mod=space&uid=895143]@version[/url]  V3.00

 * $Revision: 7 $

 * $Date: 15/05/22 2:56p $

 * [url=home.php?mod=space&uid=247401]@brief[/url]    Demonstrate how ACMP works with internal band-gap voltage.

 *

 * @note

 * Copyright (C) 2014 Nuvoton Technology Corp. All rights reserved.

*****************************************************************************/

#include <stdio.h>

#include "M051Series.h"



/* Function prototype declaration */

void SYS_Init(void);



int32_t main(void)

{

    /* Unlock protected registers */

    SYS_UnlockReg();

    /* Init System, IP clock and multi-function I/O. */

    SYS_Init();

    /* Lock protected registers */

    SYS_LockReg();



    /* Configure UART0: 115200, 8-bit word, no parity bit, 1 stop bit. */

    UART_Open(UART0, 115200);



    printf("\n\n");

    printf("+---------------------------------------+\n");

    printf("|         M051 ACMP Sample Code         |\n");

    printf("+---------------------------------------+\n");



    printf("\nThis sample code demonstrates ACMP0 function. Using ACMP0_P (P1.5) as ACMP0\n");

    printf("positive input and using internal band-gap voltage as the negative input\n");

    printf("The compare result reflects on ACMP0_O (P3.6)\n");



    /* Configure ACMP0. Enable ACMP0 and select internal reference voltage as negative input. */

    ACMP_Open(ACMP01, 0, ACMP_CR_VNEG_BANDGAP, ACMP_CR_HYSTERESIS_DISABLE);

    /* Enable ACMP0 interrupt function */

    ACMP_ENABLE_INT(ACMP01, 0);



    /* Enable ACMP01 interrupt */

    NVIC_EnableIRQ(ACMP01_IRQn);



    while(1);



}



void ACMP01_IRQHandler(void)

{

    static uint32_t u32Cnt = 0;



    /* Clear ACMP 0 interrupt flag */

    ACMP_CLR_INT_FLAG(ACMP01, 0);

    /* Check Comparator 0 Output Status */

    if(ACMP_GET_OUTPUT(ACMP01, 0))

        printf("ACMP0_P voltage > Band-gap voltage (%d)\n", u32Cnt);

    else

        printf("ACMP0_P voltage <= Band-gap voltage (%d)\n", u32Cnt);



    u32Cnt++;

}





void SYS_Init(void)

{

    /*---------------------------------------------------------------------------------------------------------*/

    /* Init System Clock                                                                                       */

    /*---------------------------------------------------------------------------------------------------------*/



    /* Enable external 12MHz XTAL */

    CLK_EnableXtalRC(CLK_PWRCON_XTL12M_EN_Msk);



    /* Waiting for clock ready */

    CLK_WaitClockReady(CLK_CLKSTATUS_XTL12M_STB_Msk);



    /* Select HXT as the clock source of UART */

    CLK_SetModuleClock(UART0_MODULE, CLK_CLKSEL1_UART_S_HXT, CLK_CLKDIV_UART(1));



    /* Enable UART peripheral clock */

    CLK_EnableModuleClock(UART0_MODULE);

    /* Enable ACMP01 peripheral clock */

    CLK_EnableModuleClock(ACMP01_MODULE);



    /* Update System Core Clock */

    /* User can use SystemCoreClockUpdate() to calculate SystemCoreClock and CyclesPerUs automatically. */

    SystemCoreClockUpdate();





    /*---------------------------------------------------------------------------------------------------------*/

    /* Init I/O Multi-function                                                                                 */

    /*---------------------------------------------------------------------------------------------------------*/

    /* Set P1.5 multi-function pin for ACMP0 positive input pin */

    SYS->P1_MFP = SYS_MFP_P15_ACMP0_P;



    /* Disable digital input path of analog pin ACMP0_P to prevent leakage */

    GPIO_DISABLE_DIGITAL_PATH(P1, BIT5);



    /* Set P3 multi-function pins for UART0 RXD, TXD and ACMP0 output */

    SYS->P3_MFP = SYS_MFP_P30_RXD0 | SYS_MFP_P31_TXD0 | SYS_MFP_P36_ACMP0_O;

}



/*** (C) COPYRIGHT 2014 Nuvoton Technology Corp. ***/