ACMP窗口锁存模式应用

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

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

 * [url=home.php?mod=space&uid=895143]@version[/url]  V1.00

 * [url=home.php?mod=space&uid=247401]@brief[/url]    Demonstrate how to use ACMP window latch mode.

 *

 * SPDX-License-Identifier: Apache-2.0

 * [url=home.php?mod=space&uid=17282]@CopyRight[/url] (C) 2018 Nuvoton Technology Corp. All rights reserved.

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

#include <stdio.h>

#include "NuMicro.h"





void ACMP01_IRQHandler(void)

{

    static uint32_t u32Cnt = 0;



    /* Clear ACMP 1 interrupt flag */

    ACMP_CLR_INT_FLAG(ACMP01, 1);

    /* Check Comparator 1 Output Status */

    if(ACMP_GET_OUTPUT(ACMP01, 1))

        printf("ACMP1_P voltage > Band-gap voltage (%d)\n", u32Cnt);

    else

        printf("ACMP1_P voltage <= Band-gap voltage (%d)\n", u32Cnt);



    u32Cnt++;

}





void SYS_Init(void)

{

    /* Unlock protected registers */

    SYS_UnlockReg();



    /* Enable HIRC */

    CLK_EnableXtalRC(CLK_PWRCTL_HIRCEN_Msk);



    /* Waiting for HIRC clock ready */

    CLK_WaitClockReady(CLK_STATUS_HIRCSTB_Msk);



    /* Switch HCLK clock source to HIRC */

    CLK_SetHCLK(CLK_CLKSEL0_HCLKSEL_HIRC, CLK_CLKDIV0_HCLK(1));



    /* Set both PCLK0 and PCLK1 as HCLK/2 */

    CLK->PCLKDIV = (CLK_PCLKDIV_APB0DIV_DIV2 | CLK_PCLKDIV_APB1DIV_DIV2);



    /* Switch UART0 clock source to HIRC */

    CLK_SetModuleClock(UART0_MODULE, CLK_CLKSEL1_UART0SEL_HIRC, CLK_CLKDIV0_UART0(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 PllClock, SystemCoreClock and CycylesPerUs automatically. */

    SystemCoreClockUpdate();



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

    /* Init I/O Multi-function                                              */

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

    /* Set GPB multi-function pins for UART0 RXD and TXD */

    SYS->GPB_MFPH = (SYS->GPB_MFPH & ~(SYS_GPB_MFPH_PB12MFP_Msk | SYS_GPB_MFPH_PB13MFP_Msk)) |

                    (SYS_GPB_MFPH_PB12MFP_UART0_RXD | SYS_GPB_MFPH_PB13MFP_UART0_TXD);



    /* Set PB4 multi-function pin for ACMP1 positive input pin and PB6 multi-function pin for ACMP1 output pin */

    SYS->GPB_MFPL = (SYS->GPB_MFPL & ~(SYS_GPB_MFPL_PB4MFP_Msk | GPIO_MODE_MODE6_Msk)) |

                    (SYS_GPB_MFPL_PB4MFP_ACMP1_P1 | SYS_GPB_MFPL_PB6MFP_ACMP1_O);

    /* Disable digital input path of analog pin ACMP1_P1 to prevent leakage */

    GPIO_DISABLE_DIGITAL_PATH(PB, BIT4);

    /* Set PB.4 to input mode for ACMP analog input pins */

    GPIO_SetMode(PB, BIT4, GPIO_MODE_INPUT);



    /* Set PA.6 multi-function pin for ACMP1 window latch pin */

    SYS->GPA_MFPL = (SYS->GPA_MFPL & ~(SYS_GPA_MFPL_PA6MFP_Msk)) |

                    (SYS_GPA_MFPL_PA6MFP_ACMP1_WLAT);



    /* Lock protected registers */

    SYS_LockReg();

}





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

/* Init UART0                                                           */

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

void UART0_Init(void)

{

    /* Reset UART0 */

    SYS_ResetModule(UART0_RST);



    /* Configure UART0 and set UART0 baud rate */

    UART_Open(UART0, 115200);

}





/*

 * In window latch mode and window latch pin is at high level, the voltage of the positive

 * input is greater than the  voltage of the negative input, the analog comparator outputs

 * logical one; otherwise, it outputs logical zero. When window latch pin is at low level,

 * the output level does not change no matter how positive  input voltage changes.

 */



int32_t main(void)

{

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

    SYS_Init();



    /* Init UART0 for printf */

    UART0_Init();



    printf("\nThis sample code demonstrates ACMP1 window latch function. Using ACMP1_P1 (PB4) as ACMP1\n");

    printf("positive input and using internal band-gap voltage as the negative input. ACMP1_WLAT is at\n");

    printf("PA6, when PA6 is low, compare result on ACMP1_O (PB6) does not change with ACMP1_P1. When PA6\n");

    printf("is high, ACMP1_O works as usual\n");



    printf("Press any key to start ...");

    getchar();

    printf("\n");



    /* Configure ACMP1. Enable ACMP1 and select band-gap voltage as the source of ACMP negative input. */

    ACMP_Open(ACMP01, 1, ACMP_CTL_NEGSEL_VBG, ACMP_CTL_HYSTERESIS_DISABLE);

    /* Select P1 as ACMP positive input channel */

    ACMP_SELECT_P(ACMP01, 1, ACMP_CTL_POSSEL_P1);

    /* Enable interrupt */

    ACMP_ENABLE_INT(ACMP01, 1);

    /* Enable window latch mode */

    ACMP_ENABLE_WINDOW_LATCH(ACMP01, 1);



    /* Enable ACMP01 interrupt */

    NVIC_EnableIRQ(ACMP01_IRQn);



    while(1);

}