adc.c

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/*
 * @brief ADC example
 * This example show how to  the ADC in 3 mode : Polling, Interrupt and DMA
 *
 * @note
 * Copyright(C) NXP Semiconductors, 2012
 * All rights reserved.
 *
 * @par
 * Software that is described herein is for illustrative purposes only
 * which provides customers with programming information regarding the
 * LPC products.  This software is supplied "AS IS" without any warranties of
 * any kind, and NXP Semiconductors and its licensor disclaim any and
 * all warranties, express or implied, including all implied warranties of
 * merchantability, fitness for a particular purpose and non-infringement of
 * intellectual property rights.  NXP Semiconductors assumes no responsibility
 * or liability for the use of the software, conveys no license or rights under any
 * patent, copyright, mask work right, or any other intellectual property rights in
 * or to any products. NXP Semiconductors reserves the right to make changes
 * in the software without notification. NXP Semiconductors also makes no
 * representation or warranty that such application will be suitable for the
 * specified use without further testing or modification.
 *
 * @par
 * Permission to use, copy, modify, and distribute this software and its
 * documentation is hereby granted, under NXP Semiconductors' and its
 * licensor's relevant copyrights in the software, without fee, provided that it
 * is used in conjunction with NXP Semiconductors microcontrollers.  This
 * copyright, permission, and disclaimer notice must appear in all copies of
 * this code.
 */

#include "board.h"

/*****************************************************************************
 * Private types/enumerations/variables
 ****************************************************************************/
#ifdef BOARD_NXP_XPRESSO_1769
#define _ADC_CHANNLE ADC_CH0
#else
#define _ADC_CHANNLE ADC_CH2
#endif
#define _LPC_ADC_ID LPC_ADC
#define _LPC_ADC_IRQ ADC_IRQn
#define _GPDMA_CONN_ADC GPDMA_CONN_ADC
static char WelcomeMenu[] = "\r\nHello NXP Semiconductors \r\n"
       "ADC DEMO \r\n"
#if defined(CHIP_LPC175X_6X)       
       "Sample rate : 200kHz \r\n"
#else
       "Sample rate : 400kHz \r\n"
#endif
       "Press \'c\' to continue or \'x\' to quit\r\n"
       "Press \'o\' or \'p\' to set Sample rate\r\n"
       "Press \'b\' to ENABLE or DISABLE Burst Mode\r\n";
static char SelectMenu[] = "\r\nPress number 1-3 to choose ADC running mode:\r\n"
         "\t1: Polling Mode \r\n"
         "\t2: Interrupt Mode \r\n"
         "\t3: DMA Mode \r\n";

static ADC_Clock_Setup_T ADCSetup;
static volatile uint8_t Burst_Mode_Flag = 0, Interrupt_Continue_Flag;
static volatile uint8_t ADC_Interrupt_Done_Flag, channelTC, dmaChannelNum;
uint32_t DMAbuffer;
/*****************************************************************************
 * Public types/enumerations/variables
 ****************************************************************************/

/*****************************************************************************
 * Private functions
 ****************************************************************************/

/* Print ADC value and delay */
static void App_print_ADC_value(uint16_t data)
{
 volatile uint32_t j;
 j = 5000000;
 DEBUGOUT("ADC value is : 0x%04x\r\n", data);
 /* Delay */
 while (j--) {}
}

/* DMA routine for ADC example */
static void App_DMA_Test(void)
{
 uint16_t dataADC;

 /* Initialize GPDMA controller */
 Chip_GPDMA_Init(LPC_GPDMA);
 /* Setting GPDMA interrupt */
 NVIC_DisableIRQ(DMA_IRQn);
 NVIC_SetPriority(DMA_IRQn, ((0x01 << 3) | 0x01));
 NVIC_EnableIRQ(DMA_IRQn);
 /* Setting ADC interrupt, ADC Interrupt must be disable in DMA mode */
 NVIC_DisableIRQ(_LPC_ADC_IRQ);
 Chip_ADC_Channel_Int_Cmd(_LPC_ADC_ID, _ADC_CHANNLE, ENABLE);
 /* Get the free channel for DMA transfer */
 dmaChannelNum = Chip_DMA_GetFreeChannel(LPC_GPDMA, _GPDMA_CONN_ADC);
 /* Enable burst mode if any, the AD converter does repeated conversions
    at the rate selected by the CLKS field in burst mode automatically */
 if (Burst_Mode_Flag) {
  Chip_ADC_Burst_Cmd(_LPC_ADC_ID, ENABLE);
 }
 /* Get  adc value until get 'x' character */
 while (DEBUGIN() != 'x') {
  /* Start A/D conversion if not using burst mode */
  if (!Burst_Mode_Flag) {
   Chip_ADC_Set_StartMode(_LPC_ADC_ID, ADC_START_NOW, ADC_TRIGGERMODE_RISING);
  }
  channelTC = 0;
  Chip_DMA_Transfer(LPC_GPDMA, dmaChannelNum,
        _GPDMA_CONN_ADC,
        (uint32_t) &DMAbuffer,
        GPDMA_TRANSFERTYPE_P2M_CONTROLLER_DMA,
        1);

  /* Waiting for reading ADC value completed */
  while (channelTC == 0) {}

  /* Get the ADC value fron Data register*/
  dataADC = ADC_DR_RESULT(DMAbuffer);
  App_print_ADC_value(dataADC);
 }
 /* Disable interrupts, release DMA channel */
 Chip_DMA_Stop(LPC_GPDMA, dmaChannelNum);
 NVIC_DisableIRQ(DMA_IRQn);
 /* Disable burst mode if any */
 if (Burst_Mode_Flag) {
  Chip_ADC_Burst_Cmd(_LPC_ADC_ID, DISABLE);
 }
}

/* Interrupt routine for ADC example */
static void App_Interrupt_Test(void)
{
 /* Enable ADC Interrupt */
 NVIC_EnableIRQ(_LPC_ADC_IRQ);
 Chip_ADC_Channel_Int_Cmd(_LPC_ADC_ID, _ADC_CHANNLE, ENABLE);
 /* Enable burst mode if any, the AD converter does repeated conversions
    at the rate selected by the CLKS field in burst mode automatically */
 if (Burst_Mode_Flag) {
  Chip_ADC_Burst_Cmd(_LPC_ADC_ID, ENABLE);
 }
 Interrupt_Continue_Flag = 1;
 ADC_Interrupt_Done_Flag = 1;
 while (Interrupt_Continue_Flag) {
  if (!Burst_Mode_Flag && ADC_Interrupt_Done_Flag) {
   ADC_Interrupt_Done_Flag = 0;
   Chip_ADC_Set_StartMode(_LPC_ADC_ID, ADC_START_NOW, ADC_TRIGGERMODE_RISING);
  }
 }
 /* Disable burst mode if any */
 if (Burst_Mode_Flag) {
  Chip_ADC_Burst_Cmd(_LPC_ADC_ID, DISABLE);
 }
 /* Disable ADC interrupt */
 NVIC_DisableIRQ(_LPC_ADC_IRQ);
}

/* Polling routine for ADC example */
static void App_Polling_Test(void)
{
 uint16_t dataADC;

 /* Select using burst mode or not */
 if (Burst_Mode_Flag) {
  Chip_ADC_Burst_Cmd(_LPC_ADC_ID, ENABLE);
 }
 else {
  Chip_ADC_Burst_Cmd(_LPC_ADC_ID, DISABLE);
 }

 /* Get  adc value until get 'x' character */
 while (DEBUGIN() != 'x') {
  /* Start A/D conversion if not using burst mode */
  if (!Burst_Mode_Flag) {
   Chip_ADC_Set_StartMode(_LPC_ADC_ID, ADC_START_NOW, ADC_TRIGGERMODE_RISING);
  }
  /* Waiting for A/D conversion complete */
  while (Chip_ADC_Read_Status(_LPC_ADC_ID, _ADC_CHANNLE, ADC_DR_DONE_STAT) != SET) {}
  /* Read ADC value */
  Chip_ADC_Read_Value(_LPC_ADC_ID, _ADC_CHANNLE, &dataADC);
  /* Print ADC value */
  App_print_ADC_value(dataADC);
 }

 /* Disable burst mode, if any */
 if (Burst_Mode_Flag) {
  Chip_ADC_Burst_Cmd(_LPC_ADC_ID, DISABLE);
 }
}

/*****************************************************************************
 * Public functions
 ****************************************************************************/

void ADC_IRQHandler(void)
{
 uint16_t dataADC;
 /* Interrupt mode: Call the stream interrupt handler */
 NVIC_DisableIRQ(_LPC_ADC_IRQ);
 Chip_ADC_Channel_Int_Cmd(_LPC_ADC_ID, _ADC_CHANNLE, DISABLE);
 Chip_ADC_Read_Value(_LPC_ADC_ID, _ADC_CHANNLE, &dataADC);
 ADC_Interrupt_Done_Flag = 1;
 App_print_ADC_value(dataADC);
 if (DEBUGIN() != 'x') {
  NVIC_EnableIRQ(_LPC_ADC_IRQ);
  Chip_ADC_Channel_Int_Cmd(_LPC_ADC_ID, _ADC_CHANNLE, ENABLE);
 }
 else {Interrupt_Continue_Flag = 0; }
}

void DMA_IRQHandler(void)
{
 if (Chip_DMA_Interrupt(LPC_GPDMA, dmaChannelNum) == SUCCESS) {
  channelTC++;
 }
 else {
  /* Process error here */
 }
}

int main(void)
{
 bool end_Flag = false;
 uint32_t _bitRate = ADC_MAX_SAMPLE_RATE;
 uint8_t bufferUART;

 Board_Init();

 /* Chip_IOCON_PinMux(0, 25, IOCON_ADMODE_EN, IOCON_FUNC1); */
 /*ADC Init */
 Chip_ADC_Init(_LPC_ADC_ID, &ADCSetup);
 Chip_ADC_Channel_Enable_Cmd(_LPC_ADC_ID, _ADC_CHANNLE, ENABLE);

 while (!end_Flag) {
  DEBUGOUT(WelcomeMenu);
  while (!end_Flag) {
   bufferUART = 0xFF;
   bufferUART = DEBUGIN();
   if (bufferUART == 'c') {
    DEBUGOUT(SelectMenu);
    bufferUART = 0xFF;
    while (bufferUART == 0xFF) {
     bufferUART = DEBUGIN();
     if ((bufferUART != '1') && (bufferUART != '2') && (bufferUART != '3')) {
      bufferUART = 0xFF;
     }
    }
    switch (bufferUART) {
    case '1':  /* Polling Mode */
     App_Polling_Test();
     break;

    case '2':  /* Interrupt Mode */
     App_Interrupt_Test();
     break;

    case '3':  /* DMA mode */
     App_DMA_Test();
     break;
    }
    break;
   }
   else if (bufferUART == 'x') {
    end_Flag = true;
    DEBUGOUT("\r\nADC demo terminated!");
   }
   else if (bufferUART == 'o') {
    _bitRate -= _bitRate > 0 ? 1000 : 0;
    Chip_ADC_Set_SampleRate(_LPC_ADC_ID, &ADCSetup, _bitRate);
    DEBUGOUT("Rate : %d Sample/s\r\n", _bitRate);
   }
   else if (bufferUART == 'p') {
    _bitRate += _bitRate < 400000 ? 1000 : 0;
    Chip_ADC_Set_SampleRate(_LPC_ADC_ID, &ADCSetup, _bitRate);
    DEBUGOUT("Rate : %d Sample/s\r\n", _bitRate);
   }
   else if (bufferUART == 'b') {
    Burst_Mode_Flag = !Burst_Mode_Flag;
    ADCSetup.burstMode = Burst_Mode_Flag;
    Chip_ADC_Set_SampleRate(_LPC_ADC_ID, &ADCSetup, _bitRate);
    if (Burst_Mode_Flag) {
     DEBUGOUT("Burst Mode ENABLED\r\n");
    }
    else {
     DEBUGOUT("Burst Mode DISABLED\r\n");
    }
   }
  }
 }
 return 0;
}