MINI51系列的ADC转换操作方法

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

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

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

 * $Revision: 2 $

 * $Date: 15/09/24 5:50p $

 * [url=home.php?mod=space&uid=247401]@brief[/url]    Demonstrate ADC function by repeatedly convert the input of ADC

 *           channel 5 (P1.5) and shows the result on UART console.

 *

 * @note

 * Copyright (C) 2015 Nuvoton Technology Corp. All rights reserved.

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

#include <stdio.h>

#include "Mini51Series.h"



void ADC_IRQHandler(void)

{

    uint32_t u32Flag;



    // Get ADC comparator interrupt flag

    u32Flag = ADC_GET_INT_FLAG(ADC, ADC_ADF_INT);



    // Get ADC convert result

    printf("Convert result is %x\n", (uint32_t)ADC_GET_CONVERSION_DATA(ADC, 0));



    ADC_CLR_INT_FLAG(ADC, u32Flag);

}





void SYS_Init(void)

{

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

    /* Init System Clock                                                                                       */

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



    /* Unlock protected registers */

    SYS_UnlockReg();



    /* Set P5 multi-function pins for XTAL1 and XTAL2 */

    SYS->P5_MFP = SYS_MFP_P50_XTAL1 | SYS_MFP_P51_XTAL2;



    /* Enable external 12MHz XTAL, HIRC */

    CLK->PWRCON = CLK_PWRCON_OSC22M_EN_Msk | CLK_PWRCON_HXT;



    /* Waiting for clock ready */

    CLK_WaitClockReady(CLK_CLKSTATUS_OSC22M_STB_Msk | CLK_CLKSTATUS_XTL_STB_Msk);



    /* Switch HCLK clock source to XTL */

    CLK_SetHCLK(CLK_CLKSEL0_HCLK_S_XTAL,CLK_CLKDIV_HCLK(1));



    /* Enable IP clock */

    CLK_EnableModuleClock(UART_MODULE);

    CLK_EnableModuleClock(ADC_MODULE);



    /* Select IP clock source */

    CLK_SetModuleClock(UART_MODULE,CLK_CLKSEL1_UART_S_XTAL,CLK_CLKDIV_UART(1));

    CLK_SetModuleClock(ADC_MODULE,CLK_CLKSEL1_ADC_S_XTAL,CLK_CLKDIV_ADC(6));



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

    /* Init I/O Multi-function                                                                                 */

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

    /* Set P0 multi-function pins for UART RXD, TXD */

    SYS->P0_MFP = SYS_MFP_P00_TXD | SYS_MFP_P01_RXD;



    /* Set P1 multi-function pin ADC channel 5 input*/

    SYS->P1_MFP = SYS_MFP_P15_AIN5;



    /* Analog pin OFFD to prevent leakage */

    P1->OFFD |= (1 << 5) << GPIO_OFFD_OFFD_Pos;



    /* To update the variable SystemCoreClock */

    SystemCoreClockUpdate();



    /* Lock protected registers */

    SYS_LockReg();

}



int32_t main (void)

{

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

       In the end of SYS_Init() will issue SYS_LockReg()

       to lock protected register. If user want to write

       protected register, please issue SYS_UnlockReg()

       to unlock protected register if necessary */

    SYS_Init();



    /* Init UART to 115200-8n1 for print message */

    UART_Open(UART0, 115200);



    printf("\nThis sample code demonstrate ADC channel 5 conversion and printf the result on UART\n");



    // Enable channel 5

    ADC_Open(ADC, 0, 0, 0x01 << 5);



    // Power on ADC

    ADC_POWER_ON(ADC);





    // Enable ADC convert complete interrupt

    ADC_EnableInt(ADC, ADC_ADF_INT);

    NVIC_EnableIRQ(ADC_IRQn);



    while(1) {

        // Trigger ADC conversion if it is idle

        if(!ADC_IS_BUSY(ADC)) {

            ADC_START_CONV(ADC);

        }

    }



}



/*** (C) COPYRIGHT 2015 Nuvoton Technology Corp. ***/