main.c

/****************************************************************************
 * @file     main.c
 * @version  V2.0
 * $Revision: 6 $
 * $Date: 15/01/15 1:33p $
 * @brief    Perform A/D Conversion with ADC single mode.
 * @note
 * Copyright (C) 2014 Nuvoton Technology Corp. All rights reserved.
 *
 ******************************************************************************/
#include <stdio.h>
#include "NUC131.h"


#define PLL_CLOCK       50000000

/*---------------------------------------------------------------------------------------------------------*/
/* Define Function Prototypes                                                                              */
/*---------------------------------------------------------------------------------------------------------*/
void SYS_Init(void);
void UART0_Init(void);
void AdcSingleModeTest(void);


/*---------------------------------------------------------------------------------------------------------*/
/* Define global variables and constants                                                                   */
/*---------------------------------------------------------------------------------------------------------*/
volatile uint32_t g_u32AdcIntFlag;


void SYS_Init(void)
{
    /*---------------------------------------------------------------------------------------------------------*/
    /* Init System Clock                                                                                       */
    /*---------------------------------------------------------------------------------------------------------*/

    /* 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_PLL, CLK_CLKDIV_UART(1));

    /* ADC clock source is 22.1184MHz, set divider to 7, ADC clock is 22.1184/7 MHz */
    CLK_SetModuleClock(ADC_MODULE, CLK_CLKSEL1_ADC_S_HIRC, CLK_CLKDIV_ADC(7));

    /*---------------------------------------------------------------------------------------------------------*/
    /* Init I/O Multi-function                                                                                 */
    /*---------------------------------------------------------------------------------------------------------*/

    /* Set GPB multi-function pins for UART0 RXD and TXD */
    SYS->GPB_MFP &= ~(SYS_GPB_MFP_PB0_Msk | SYS_GPB_MFP_PB1_Msk);
    SYS->GPB_MFP |= SYS_GPB_MFP_PB0_UART0_RXD | SYS_GPB_MFP_PB1_UART0_TXD;

    /* Disable the GPA0 - GPA3 digital input path to avoid the leakage current. */
    GPIO_DISABLE_DIGITAL_PATH(PA, 0xF);

    /* Configure the GPA0 - GPA3 ADC analog input pins */
    SYS->GPA_MFP &= ~(SYS_GPA_MFP_PA0_Msk | SYS_GPA_MFP_PA1_Msk | SYS_GPA_MFP_PA2_Msk | SYS_GPA_MFP_PA3_Msk) ;
    SYS->GPA_MFP |= SYS_GPA_MFP_PA0_ADC0 | SYS_GPA_MFP_PA1_ADC1 | SYS_GPA_MFP_PA2_ADC2 | SYS_GPA_MFP_PA3_ADC3 ;

}

/*---------------------------------------------------------------------------------------------------------*/
/* Init UART                                                                                               */
/*---------------------------------------------------------------------------------------------------------*/
void UART0_Init()
{
    /* Reset IP */
    SYS_ResetModule(UART0_RST);

    /* Configure UART0 and set UART0 Baudrate */
    UART_Open(UART0, 115200);
}

/*---------------------------------------------------------------------------------------------------------*/
/* Function: AdcSingleModeTest                                                                             */
/*                                                                                                         */
/* Parameters:                                                                                             */
/*   None.                                                                                                 */
/*                                                                                                         */
/* Returns:                                                                                                */
/*   None.                                                                                                 */
/*                                                                                                         */
/* Description:                                                                                            */
/*   ADC single mode test.                                                                                 */
/*---------------------------------------------------------------------------------------------------------*/
void AdcSingleModeTest()
{
    uint8_t  u8Option;
    int32_t  i32ConversionData;
    uint32_t u32TimeOutCnt;

    printf("\n");
    printf("+----------------------------------------------------------------------+\n");
    printf("|                      ADC single mode sample code                     |\n");
    printf("+----------------------------------------------------------------------+\n");

    while(1)
    {
        printf("Select input mode:\n");
        printf("  [1] Single end input (channel 2 only)\n");
        printf("  [2] Differential input (channel pair 1 only)\n");
        printf("  Other keys: exit single mode test\n");
        u8Option = getchar();
        if(u8Option == '1')
        {
            /* Power on ADC module */
            ADC_POWER_ON(ADC);

            /* Set the ADC operation mode as single, input mode as single-end and enable the analog input channel 2 */
            ADC_Open(ADC, ADC_ADCR_DIFFEN_SINGLE_END, ADC_ADCR_ADMD_SINGLE, 0x1 << 2);

            /* Clear the A/D interrupt flag for safe */
            ADC_CLR_INT_FLAG(ADC, ADC_ADF_INT);

            /* Enable the ADC interrupt */
            ADC_EnableInt(ADC, ADC_ADF_INT);
            NVIC_EnableIRQ(ADC_IRQn);

            /* Reset the ADC interrupt indicator and Start A/D conversion */
            g_u32AdcIntFlag = 0;

            ADC_START_CONV(ADC);

            /* Wait ADC interrupt (g_u32AdcIntFlag will be set at IRQ_Handler function)*/
            u32TimeOutCnt = SystemCoreClock; /* 1 second time-out */
            while(g_u32AdcIntFlag == 0)
            {
                if(--u32TimeOutCnt == 0)
                {
                    printf("Wait for ADC interrupt time-out!\n");
                    return;
                }
            }

            /* Disable the ADC interrupt */
            ADC_DisableInt(ADC, ADC_ADF_INT);

            /* Get the conversion result of the ADC channel 2 */
            i32ConversionData = ADC_GET_CONVERSION_DATA(ADC, 2);
            printf("Conversion result of channel 2: 0x%X (%d)\n\n", i32ConversionData, i32ConversionData);
        }
        else if(u8Option == '2')
        {
            /* Power on ADC module */
            ADC_POWER_ON(ADC);

            /* Set the ADC operation mode as single, input mode as differential and
               enable analog input channel 2 for differential input channel pair 1 */
            ADC_Open(ADC, ADC_ADCR_DIFFEN_DIFFERENTIAL, ADC_ADCR_ADMD_SINGLE, 0x1 << 2);

            /* Clear the A/D interrupt flag for safe */
            ADC_CLR_INT_FLAG(ADC, ADC_ADF_INT);

            /* Enable the ADC interrupt */
            ADC_EnableInt(ADC, ADC_ADF_INT);
            NVIC_EnableIRQ(ADC_IRQn);

            /* Reset the ADC interrupt indicator and Start A/D conversion */
            g_u32AdcIntFlag = 0;
            ADC_START_CONV(ADC);

            /* Wait ADC interrupt (g_u32AdcIntFlag will be set at IRQ_Handler function)*/
            u32TimeOutCnt = SystemCoreClock; /* 1 second time-out */
            while(g_u32AdcIntFlag == 0)
            {
                if(--u32TimeOutCnt == 0)
                {
                    printf("Wait for ADC interrupt time-out!\n");
                    return;
                }
            }

            /* Disable the ADC interrupt */
            ADC_DisableInt(ADC, ADC_ADF_INT);

            /* Get the conversion result of the specified ADC channel */
            i32ConversionData = ADC_GET_CONVERSION_DATA(ADC, 2);
            printf("Conversion result of channel pair 1: 0x%X (%d)\n\n", i32ConversionData, i32ConversionData);
        }
        else
            return ;

    }
}



/*---------------------------------------------------------------------------------------------------------*/
/* ADC interrupt handler                                                                                   */
/*---------------------------------------------------------------------------------------------------------*/
void ADC_IRQHandler(void)
{
    g_u32AdcIntFlag = 1;
    ADC_CLR_INT_FLAG(ADC, ADC_ADF_INT); /* clear the A/D conversion flag */
}

/*---------------------------------------------------------------------------------------------------------*/
/* MAIN function                                                                                           */
/*---------------------------------------------------------------------------------------------------------*/

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();

    /* Init UART0 for printf */
    UART0_Init();

    /*---------------------------------------------------------------------------------------------------------*/
    /* SAMPLE CODE                                                                                             */
    /*---------------------------------------------------------------------------------------------------------*/

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

    /* Single Mode test */
    AdcSingleModeTest();

    /* Disable ADC module */
    ADC_Close(ADC);

    /* Disable ADC IP clock */
    CLK_DisableModuleClock(ADC_MODULE);

    /* Disable External Interrupt */
    NVIC_DisableIRQ(ADC_IRQn);

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

    while(1);

}