利用ADC内部通道测量温度

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

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

 * @brief

 *           Use ADC measure internal temperature sensor.

 * @note

 * Copyright (C) 2019 Nuvoton Technology Corp. All rights reserved.

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

#include <stdio.h>

#include "M051Series.h"



#define PLL_CLOCK       ((uint32_t)50000000)  //PLL clock setting     ,Unit : Hz

#define VBG             ((double)1.20)        //M051 Band-gap voltage ,Unit : Volt

#define Offset          ((uint32_t)724)       //Temperature sensor curve formula offset

#define Gain            ((double)-1.75)       //Temperature sensor curve formula gain



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

/* Global variables                                                          */

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

char ai8TemperatureUnit[] = "\u2103";         //Degree Celsies encode



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

/* Functions                                                                 */

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

void SYS_Init(void);

void UART0_Init(void);

void ADC_Example_InternalTemperature(void);



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

   Function:    SYS_Init

   Parameters:  None.

   Returns:     None.

   Description: System and periphial module clock setting.

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

void SYS_Init(void)

{



    /* Enable Internal RC 22.1184MHz clock */

    CLK_EnableXtalRC(CLK_PWRCON_OSC22M_EN_Msk);



    /* Waiting for Internal RC clock ready */

    CLK_WaitClockReady(CLK_CLKSTATUS_OSC22M_STB_Msk);



    /* Switch HCLK clock source to Internal RC and HCLK source divide 1 */

    CLK_SetHCLK(CLK_CLKSEL0_HCLK_S_HIRC, CLK_CLKDIV_HCLK(1));



    /* Enable external XTAL 12MHz clock */

    CLK_EnableXtalRC(CLK_PWRCON_XTL12M_EN_Msk);



    /* Waiting for external XTAL clock ready */

    CLK_WaitClockReady(CLK_CLKSTATUS_XTL12M_STB_Msk);



    /* Set core clock as PLL_CLOCK from PLL */

    CLK_SetCoreClock(PLL_CLOCK);



    /* Enable UART module clock */

    CLK_EnableModuleClock(UART0_MODULE);



    /* Enable ADC module clock */

    CLK_EnableModuleClock(ADC_MODULE);



    /* Select UART module clock source */

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



    /* ADC clock source is 22.1184MHz, set divider to 100, ADC clock is 22.1184/100 MHz */

    CLK_SetModuleClock(ADC_MODULE, CLK_CLKSEL1_ADC_S_HIRC, CLK_CLKDIV_ADC(100));



}



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

   Function:    UART0_Init

   Parameters:  None.

   Returns:     None.

   Description: Initialize UART0 module, setting buadrate is 115200 bps

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

void UART0_Init(void)

{

    /* Reset IP */

    SYS_ResetModule(UART0_RST);



    /* Configure UART0 and set UART0 Baudrate */

    UART_Open(UART0, 115200);

}



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

   Function:    ADC_Example_InternalTemperature

   Parameters:  None.

   Returns:     None.

   Description: Measure chip band-gap voltage through ADC, and estimate 

                external reference voltage. Measure chip internal temperature,

                according to temperature sensor curve formula and comparison 

                voltage of reference. Finally printf out the Celsius. 

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

void ADC_Example_InternalTemperature(void)

{

    int32_t  i32ConversionData;

    double   dVref;

    double   dTempData;



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

    printf("|               ADC for temperature sensor example code                |\n");

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



    printf("\nIn this example, software will get value from temperature sensor.\n");



    /* Enable Temperature Sensor function */

    SYS->TEMPCR |= SYS_TEMPCR_VTEMP_EN_Msk;



    /* Set the ADC operation mode as continuous scan, input mode as single-end and

    enable the analog input channel 7 */

    ADC_Open(ADC, ADC_ADCR_DIFFEN_SINGLE_END, ADC_ADCR_ADMD_CONTINUOUS, BIT7);



    /* Configure the analog input source of channel 7 */

    ADC_CONFIG_CH7(ADC, ADC_ADCHER_PRESEL_INT_BANDGAP);



    /* Power on ADC module */

    ADC_POWER_ON(ADC);



    /* clear the A/D interrupt flag for safe */

    ADC_CLR_INT_FLAG(ADC, ADC_ADF_INT);



    /* start A/D conversion */

    ADC_START_CONV(ADC);



    while (1)

    {

        /* Wait conversion done */

        while (!ADC_GET_INT_FLAG(ADC, ADC_ADF_INT));



        /* Stop A/D conversion */

        ADC_STOP_CONV(ADC);



        /* clear the A/D interrupt flag for safe */

        ADC_CLR_INT_FLAG(ADC, ADC_ADF_INT);



        /* Calculate dVref by using conversion result of VBG */

        /* ConversionData = VBG * 4096 / Vref */

        i32ConversionData = ADC_GET_CONVERSION_DATA(ADC, 7);

        dVref = VBG * 4096 / (double)i32ConversionData;



        /* Delay */

        CLK_SysTickDelay(500000);



        /* Configure the analog input source of channel 7 */

        ADC_CONFIG_CH7(ADC, ADC_ADCHER_PRESEL_INT_TEMPERATURE_SENSOR);



        /* start A/D conversion */

        ADC_START_CONV(ADC);



        /* Wait conversion done */

        while (!ADC_GET_INT_FLAG(ADC, ADC_ADF_INT));



        /* Stop A/D conversion */

        ADC_STOP_CONV(ADC);



        /* clear the A/D interrupt flag for safe */

        ADC_CLR_INT_FLAG(ADC, ADC_ADF_INT);



        /* Calculate value from temperature sensor  */

        /* ConversionData = Vtemp(V) * 4096 / dVref */

        /* Vtemp(mV) = Gain * Temperature + Offset  */

        i32ConversionData = ADC_GET_CONVERSION_DATA(ADC, 7);

        dTempData = (((double)i32ConversionData * dVref / 4096) * 1000 - Offset) / Gain;

        printf("Conversion result of channel %d: 0x%X (%.2f %s)\n", 7, i32ConversionData, dTempData, ai8TemperatureUnit);



        /* Delay */

        CLK_SysTickDelay(500000);



        /* Configure the analog input source of channel 7 */

        ADC_CONFIG_CH7(ADC, ADC_ADCHER_PRESEL_INT_BANDGAP);



        /* start A/D conversion */

        ADC_START_CONV(ADC);

    }

}



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

   Function:    main

   Parameters:  None.

   Returns:     None.

   Description: main routine of the example.

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

int main(void)

{



    /* Unlock protected registers */

    SYS_UnlockReg();



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

    SYS_Init();



    /* Lock protected registers */

    SYS_LockReg();



    /* Init UART0 for printf */

    UART0_Init();



    printf("\nSystem clock rate: %d Hz\n", SystemCoreClock);



    /* Internal Temperature */

    ADC_Example_InternalTemperature();



    /* Disable ADC module */

    ADC_Close(ADC);



    /* Disable ADC IP clock */

    CLK_DisableModuleClock(ADC_MODULE);



    /* Disable External Interrupt */

    NVIC_DisableIRQ(ADC_IRQn);



    printf("\nExit ADC example code\n");



    while (1);



}