ssp.c

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/*
 * @brief SSP example
 * This example show how to use the SSP in 3 modes : 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"
#include "stdio.h"

/*****************************************************************************
 * Private types/enumerations/variables
 ****************************************************************************/

#define LPC_SSP           LPC_SSP1
#define SSP_IRQ           SSP1_IRQn
#define LPC_GPDMA_SSP_TX  GPDMA_CONN_SSP1_Tx
#define LPC_GPDMA_SSP_RX  GPDMA_CONN_SSP1_Rx
#define SSPIRQHANDLER     SSP1_IRQHandler

#define BUFFER_SIZE                         (0x100)
#define SSP_DATA_BITS                       (SSP_BITS_8)
#define SSP_DATA_BIT_NUM(databits)          (databits + 1)
#define SSP_DATA_BYTES(databits)            (((databits) > SSP_BITS_8) ? 2 : 1)
#define SSP_LO_BYTE_MSK(databits)           ((SSP_DATA_BYTES(databits) > 1) ? 0xFF : (0xFF >> \
                       (8 - SSP_DATA_BIT_NUM(databits))))
#define SSP_HI_BYTE_MSK(databits)           ((SSP_DATA_BYTES(databits) > 1) ? (0xFF >> \
                      (16 - SSP_DATA_BIT_NUM(databits))) : 0)

#define SSP_MODE_SEL                        (0x31)
#define SSP_TRANSFER_MODE_SEL               (0x32)
#define SSP_MASTER_MODE_SEL                 (0x31)
#define SSP_SLAVE_MODE_SEL                  (0x32)
#define SSP_POLLING_SEL                     (0x31)
#define SSP_INTERRUPT_SEL                   (0x32)
#define SSP_DMA_SEL                         (0x33)

/* Tx buffer */
static uint8_t Tx_Buf[BUFFER_SIZE];

/* Rx buffer */
static uint8_t Rx_Buf[BUFFER_SIZE];

static SSP_ConfigFormat ssp_format;
static Chip_SSP_DATA_SETUP_T xf_setup;
static volatile uint8_t  isXferCompleted = 0;
static uint8_t dmaChSSPTx, dmaChSSPRx;
static volatile uint8_t isDmaTxfCompleted = 0;
static volatile uint8_t isDmaRxfCompleted = 0;

#if defined(DEBUG_ENABLE)
static char sspWaitingMenu[] = "SSP Polling: waiting for transfer ...\n\r";
static char sspIntWaitingMenu[]  = "SSP Interrupt: waiting for transfer ...\n\r";
static char sspDMAWaitingMenu[]  = "SSP DMA: waiting for transfer ...\n\r";

static char sspPassedMenu[] = "SSP: Transfer PASSED\n\r";
static char sspFailedMenu[] = "SSP: Transfer FAILED\n\r";

static char sspTransferModeSel[] = "\n\rPress 1-3 or 'q' to quit\n\r"
           "\t 1: SSP Polling Read Write\n\r"
           "\t 2: SSP Int Read Write\n\r"
           "\t 3: SSP DMA Read Write\n\r";

static char helloMenu[] = "Hello NXP Semiconductors \n\r";
static char sspMenu[] = "SSP demo \n\r";
static char sspMainMenu[] = "\t 1: Select SSP Mode (Master/Slave)\n\r"
       "\t 2: Select Transfer Mode\n\r";
static char sspSelectModeMenu[] = "\n\rPress 1-2 to select or 'q' to quit:\n\r"
          "\t 1: Master \n\r"
          "\t 2: Slave\n\r";
#endif /* defined(DEBUG_ENABLE) */

/*****************************************************************************
 * Public types/enumerations/variables
 ****************************************************************************/

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

/* Initialize buffer */
static void Buffer_Init(void)
{
 uint16_t i;
 uint8_t ch = 0;

 for (i = 0; i < BUFFER_SIZE; i++) {
  Tx_Buf[i] = ch++;
  Rx_Buf[i] = 0xAA;
 }
}

/* Verify buffer after transfer */
static uint8_t Buffer_Verify(void)
{
 uint16_t i;
 uint8_t *src_addr = (uint8_t *) &Tx_Buf[0];
 uint8_t *dest_addr = (uint8_t *) &Rx_Buf[0];

 for ( i = 0; i < BUFFER_SIZE; i++ ) {

  if (((*src_addr) & SSP_LO_BYTE_MSK(ssp_format.bits)) !=
   ((*dest_addr) & SSP_LO_BYTE_MSK(ssp_format.bits))) {
   return 1;
  }
  src_addr++;
  dest_addr++;

  if (SSP_DATA_BYTES(ssp_format.bits) == 2) {
   if (((*src_addr) & SSP_HI_BYTE_MSK(ssp_format.bits)) !=
    ((*dest_addr) & SSP_HI_BYTE_MSK(ssp_format.bits))) {
    return 1;
   }
   src_addr++;
   dest_addr++;
   i++;
  }
 }
 return 0;
}

/* Select the Transfer mode : Polling, Interrupt or DMA */
static void appSSPTest(void)
{
 int key;

 DEBUGOUT(sspTransferModeSel);

 dmaChSSPTx = Chip_DMA_GetFreeChannel(LPC_GPDMA, LPC_GPDMA_SSP_TX);
 dmaChSSPRx = Chip_DMA_GetFreeChannel(LPC_GPDMA, LPC_GPDMA_SSP_RX);

 xf_setup.length = BUFFER_SIZE;
 xf_setup.tx_data = Tx_Buf;
 xf_setup.rx_data = Rx_Buf;

 while (1) {
  key = 0xFF;
  do {
   key = DEBUGIN();
  } while ((key & 0xFF) == 0xFF);

  Buffer_Init();

  switch (key) {
  case SSP_POLLING_SEL: /* SSP Polling Read Write Mode */
   DEBUGOUT(sspWaitingMenu);
   xf_setup.rx_cnt = xf_setup.tx_cnt = 0;

   Chip_SSP_RWFrames_Blocking(LPC_SSP, &xf_setup);

   if (Buffer_Verify() == 0) {
    DEBUGOUT(sspPassedMenu);
   }
   else {
    DEBUGOUT(sspFailedMenu);
   }
   break;

  case SSP_INTERRUPT_SEL:
   DEBUGOUT(sspIntWaitingMenu);

   isXferCompleted = 0;
   xf_setup.rx_cnt = xf_setup.tx_cnt = 0;

   Chip_SSP_Int_FlushData(LPC_SSP);/* flush dummy data from SSP FiFO */
   if (SSP_DATA_BYTES(ssp_format.bits) == 1) {
    Chip_SSP_Int_RWFrames8Bits(LPC_SSP, &xf_setup);
   }
   else {
    Chip_SSP_Int_RWFrames16Bits(LPC_SSP, &xf_setup);
   }

   Chip_SSP_Int_Enable(LPC_SSP); /* enable interrupt */
   while (!isXferCompleted) {}

   if (Buffer_Verify() == 0) {
    DEBUGOUT(sspPassedMenu);
   }
   else {
    DEBUGOUT(sspFailedMenu);
   }
   break;

  case SSP_DMA_SEL: /* SSP DMA Read and Write: fixed on 8bits */
   DEBUGOUT(sspDMAWaitingMenu);
   isDmaTxfCompleted = isDmaRxfCompleted = 0;
   Chip_SSP_DMA_Enable(LPC_SSP);
   /* data Tx_Buf --> SSP */
   Chip_DMA_Transfer(LPC_GPDMA, dmaChSSPTx,
         (uint32_t) &Tx_Buf[0],
         LPC_GPDMA_SSP_TX,
         GPDMA_TRANSFERTYPE_M2P_CONTROLLER_DMA,
         BUFFER_SIZE);
   /* data SSP --> Rx_Buf */
   Chip_DMA_Transfer(LPC_GPDMA, dmaChSSPRx,
         LPC_GPDMA_SSP_RX,
         (uint32_t) &Rx_Buf[0],
         GPDMA_TRANSFERTYPE_P2M_CONTROLLER_DMA,
         BUFFER_SIZE);

   while (!isDmaTxfCompleted || !isDmaRxfCompleted) {}
   if (Buffer_Verify() == 0) {
    DEBUGOUT(sspPassedMenu);
   }
   else {
    DEBUGOUT(sspFailedMenu);
   }
   Chip_SSP_DMA_Disable(LPC_SSP);
   break;

  case 'q':
  case 'Q':
   Chip_DMA_Stop(LPC_GPDMA, dmaChSSPTx);
   Chip_DMA_Stop(LPC_GPDMA, dmaChSSPRx);
   return;

  default:
   break;
  }

  DEBUGOUT(sspTransferModeSel);
 }

}

/* Select the SSP mode : Master or Slave */
static void appSSPSelectModeMenu(void)
{
 int key;

 DEBUGOUT(sspSelectModeMenu);

 while (1) {
  key = 0xFF;
  do {
   key = DEBUGIN();
  } while ((key & 0xFF) == 0xFF);

  switch (key) {
  case SSP_MASTER_MODE_SEL: /* Master */
   Chip_SSP_SetMaster(LPC_SSP, 1);
   DEBUGOUT("Master Mode\n\r");
   return;

  case SSP_SLAVE_MODE_SEL: /* Slave */
   Chip_SSP_SetMaster(LPC_SSP, 0);
   DEBUGOUT("Slave Mode\n\r");
   return;

  case 'q':
   return;

  default:
   break;
  }
  DEBUGOUT(sspSelectModeMenu);
 }

}

/* The main menu of the example. Allow user select the SSP mode (master or slave) and Transfer
   mode (Polling, Interrupt or DMA) */
static void appSSPMainMenu(void)
{
 int key;

 DEBUGOUT(helloMenu);
 DEBUGOUT(sspMenu);
 DEBUGOUT(sspMainMenu);

 while (1) {
  key = 0xFF;
  do {
   key = DEBUGIN();
  } while ((key & 0xFF) == 0xFF);

  switch (key) {
  case SSP_MODE_SEL: /* Select SSP Mode */
   appSSPSelectModeMenu();
   break;

  case SSP_TRANSFER_MODE_SEL: /* Select Transfer Mode */
   appSSPTest();
   break;

  default:
   break;
  }
  DEBUGOUT(sspMainMenu);
 }
}

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

void SSPIRQHANDLER(void)
{
 Chip_SSP_Int_Disable(LPC_SSP); /* Disable all interrupt */
 if (SSP_DATA_BYTES(ssp_format.bits) == 1) {
  Chip_SSP_Int_RWFrames8Bits(LPC_SSP, &xf_setup);
 }
 else {
  Chip_SSP_Int_RWFrames16Bits(LPC_SSP, &xf_setup);
 }

 if ((xf_setup.rx_cnt != xf_setup.length) || (xf_setup.tx_cnt != xf_setup.length)) {
  Chip_SSP_Int_Enable(LPC_SSP); /* enable all interrupts */
 }
 else {
  isXferCompleted = 1;
 }
}

void DMA_IRQHandler(void)
{
 if (Chip_DMA_Interrupt(LPC_GPDMA, dmaChSSPTx) == SUCCESS) {
  isDmaTxfCompleted = 1;
 }

 if (Chip_DMA_Interrupt(LPC_GPDMA, dmaChSSPRx) == SUCCESS) {
  isDmaRxfCompleted = 1;
 }
}

int main(void)
{
 Board_Init();

 /* SSP initialization */
 Board_SSP_Init(LPC_SSP);

 Chip_SSP_Init(LPC_SSP);

 ssp_format.frameFormat = SSP_FRAMEFORMAT_SPI;
 ssp_format.bits = SSP_DATA_BITS;
 ssp_format.clockMode = SSP_CLOCK_MODE0;
 Chip_SSP_SetFormat(LPC_SSP, &ssp_format);

 Chip_SSP_Enable(LPC_SSP);

 /* 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 SSP interrupt */
 NVIC_EnableIRQ(SSP_IRQ);

 appSSPMainMenu();

 /* DeInitialize SSP peripheral */
 Chip_SSP_DeInit(LPC_SSP);

 return 0;
}