uart.c

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/*
 * @brief UART example
 * This example show how to use the UART 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"

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

#if defined(BOARD_EA_DEVKIT_17884088)
#define UARTNum 0
#elif defined(BOARD_NXP_XPRESSO_1769)
#define UARTNum 3
#else
#error No UART selected for undefined board
#endif

#if (UARTNum == 0)
#define LPC_UART LPC_UART0
#define UARTx_IRQn  UART0_IRQn
#define UARTx_IRQHandler UART0_IRQHandler
#define _GPDMA_CONN_UART_Tx GPDMA_CONN_UART0_Tx
#define _GPDMA_CONN_UART_Rx GPDMA_CONN_UART0_Rx
#elif (UARTNum == 1)
#define LPC_UART LPC_UART1
#define UARTx_IRQn  UART1_IRQn
#define UARTx_IRQHandler UART1_IRQHandler
#define _GPDMA_CONN_UART_Tx GPDMA_CONN_UART1_Tx
#define _GPDMA_CONN_UART_Rx GPDMA_CONN_UART1_Rx
#elif (UARTNum == 2)
#define LPC_UART LPC_UART2
#define UARTx_IRQn  UART2_IRQn
#define UARTx_IRQHandler UART2_IRQHandler
#define _GPDMA_CONN_UART_Tx GPDMA_CONN_UART2_Tx
#define _GPDMA_CONN_UART_Rx GPDMA_CONN_UART2_Rx
#elif (UARTNum == 3)
#define LPC_UART LPC_UART3
#define UARTx_IRQn  UART3_IRQn
#define UARTx_IRQHandler UART3_IRQHandler
#define _GPDMA_CONN_UART_Tx GPDMA_CONN_UART3_Tx
#define _GPDMA_CONN_UART_Rx GPDMA_CONN_UART3_Rx
#endif

static uint8_t uartABComplete[] = "UART Auto-Baurate synchronized! \n\r";

/* Uart Polling variables and functions declaration */
static uint8_t uartPolling_menu1[] = "Hello NXP Semiconductors \n\r";
static uint8_t uartPolling_menu2[] = "UART polling mode demo \n\r";
static uint8_t uartPolling_menu3[] = "\n\rUART demo terminated!";
static uint8_t uartPolling_menu4[] = "\n\rPress number 1-3 to choose UART running mode:\n\r"
          "\t 1: Polling Mode \n\r"
          "\t 2: Interrupt Mode \n\r"
          "\t 3: DMA Mode \n\r";
static uint8_t uartPolling_menu5[] = "\n\rPolling mode is running now! Please press \'c\' and choose another mode \n\r";

/* Uart Interrupt variables and functions declaration */
static uint8_t uart_interrupt_menu[] =
 "UART Interrupt mode demo ! \n\rPress '1' to '4' to display 4 menus \n\rPress 'x'to exist uart interrupt mode \n\r";
static uint8_t uart_interrupt_menu1[] = "UART interrupt menu 1 \n\r";
static uint8_t uart_interrupt_menu2[] = "UART interrupt menu 2 \n\r";
static uint8_t uart_interrupt_menu3[] = "UART interrupt menu 3 \n\r";
static uint8_t uart_interrupt_menu4[] = "UART interrupt menu 4 \n\r";
/* static uint8_t rxUartIntBuf[1]; */

#define DMA_TIMEOUT 0xA000000

/* DMA variables and functions declaration */
static uint8_t dmaChannelNumTx, dmaChannelNumRx;
static uint8_t uartDMA_menu[] = "Hello NXP Semiconductors (DMA mode)\n\r"
        "UART DMA mode demo ! Please type 'hello NXP' to return\n\r";

static volatile uint32_t channelTC; /* Terminal Counter flag for Channel */
static volatile uint32_t channelTCErr;
static FunctionalState  isDMATx = ENABLE;

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

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

/* Initialize DMA for UART, enable DMA controller and enable DMA interrupt */
static void App_DMA_Init(void)
{
 /* 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);
}

/* DeInitialize DMA for UART, free transfer channels and disable DMA interrupt */
static void App_DMA_DeInit(void)
{
 Chip_DMA_Stop(LPC_GPDMA, dmaChannelNumTx);
 Chip_DMA_Stop(LPC_GPDMA, dmaChannelNumRx);
 NVIC_DisableIRQ(DMA_IRQn);
}

/* DMA routine for example_uart */
static void App_DMA_Test(void)
{
 uint8_t receiveBuffer[16];

 App_DMA_Init();
 dmaChannelNumTx = Chip_DMA_GetFreeChannel(LPC_GPDMA, _GPDMA_CONN_UART_Tx);

 isDMATx = ENABLE;
 channelTC = channelTCErr = 0;
 Chip_DMA_Transfer(LPC_GPDMA, dmaChannelNumTx,
       (uint32_t) &uartDMA_menu[0],
       _GPDMA_CONN_UART_Tx,
       GPDMA_TRANSFERTYPE_M2P_CONTROLLER_DMA,
       sizeof(uartDMA_menu));
 while (!channelTC) {}

 dmaChannelNumRx = Chip_DMA_GetFreeChannel(LPC_GPDMA, _GPDMA_CONN_UART_Rx);
 isDMATx = DISABLE;
 channelTC = channelTCErr = 0;
 Chip_DMA_Transfer(LPC_GPDMA, dmaChannelNumRx,
       _GPDMA_CONN_UART_Rx,
       (uint32_t) &receiveBuffer[0],
       GPDMA_TRANSFERTYPE_P2M_CONTROLLER_DMA,
       10);
 while (!channelTC) {}

 isDMATx = ENABLE;
 channelTC = channelTCErr = 0;
 Chip_DMA_Transfer(LPC_GPDMA, dmaChannelNumTx,
       (uint32_t) &receiveBuffer[0],
       _GPDMA_CONN_UART_Tx,
       GPDMA_TRANSFERTYPE_M2P_CONTROLLER_DMA,
       10);
 while (!channelTC) {}

 App_DMA_DeInit();
}

/* Print Welcome Screen Menu subroutine by Interrupt mode */
static void Print_Menu_Interrupt(LPC_USART_T *UARTx)
{
 uint32_t tmp, tmp2;
 uint8_t *pDat;

 tmp = sizeof(uart_interrupt_menu);
 tmp2 = 0;
 pDat = (uint8_t *) &uart_interrupt_menu[0];
 while (tmp) {
  tmp2 = Chip_UART_Interrupt_Transmit(UARTx, pDat, tmp);
  pDat += tmp2;
  tmp -= tmp2;
 }
}

/* Initialize Interrupt for UART */
static void App_Interrupt_Init(void)
{
 /* Enable UART Rx interrupt */
 Chip_UART_IntConfig(LPC_UART, UART_INTCFG_RBR, ENABLE);
 /* Enable UART line status interrupt */
 Chip_UART_IntConfig(LPC_UART, UART_INTCFG_RLS, ENABLE);
 /*
  * Do not enable transmit interrupt here, since it is handled by
  * UART_Send() function, just to reset Tx Interrupt state for the
  * first time
  */
 Chip_UART_InitRingBuffer(LPC_UART);
 /* Enable Interrupt for UART channel */
 /* Priority = 1 */
 NVIC_SetPriority(UARTx_IRQn, 1);
 /* Enable Interrupt for UART channel */
 NVIC_EnableIRQ(UARTx_IRQn);
}

/* DeInitialize Interrupt for UART */
static void App_Interrupt_DeInit(void)
{
 /* Disable UART Rx interrupt */
 Chip_UART_IntConfig(LPC_UART, UART_INTCFG_RBR, DISABLE);
 /* Disable UART line status interrupt */
 Chip_UART_IntConfig(LPC_UART, UART_INTCFG_RLS, DISABLE);
 /* Disable Interrupt for UART channel */
 NVIC_DisableIRQ(UARTx_IRQn);
}

/* Interrupt routine for example_uart */
static void App_Interrupt_Test(void)
{
 uint8_t isExit = 0, userInput;
 uint32_t len;
 App_Interrupt_Init();

 /* Print out uart interrupt menu */
 Print_Menu_Interrupt(LPC_UART);

 while (!isExit) {
  len = 0;
  while (len == 0) {
   len = Chip_UART_Interrupt_Receive(LPC_UART, &userInput, 1);
  }
  if (userInput == '1') {
   Chip_UART_Interrupt_Transmit(LPC_UART, (uint8_t *) &uart_interrupt_menu1[0], sizeof(uart_interrupt_menu1));
  }
  else if (userInput == '2') {
   Chip_UART_Interrupt_Transmit(LPC_UART, (uint8_t *) &uart_interrupt_menu2[0], sizeof(uart_interrupt_menu2));
  }
  else if (userInput == '3') {
   Chip_UART_Interrupt_Transmit(LPC_UART, (uint8_t *) &uart_interrupt_menu3[0], sizeof(uart_interrupt_menu3));
  }
  else if (userInput == '4') {
   Chip_UART_Interrupt_Transmit(LPC_UART, (uint8_t *) &uart_interrupt_menu4[0], sizeof(uart_interrupt_menu4));
  }
  else if (( userInput == 'x') || ( userInput == 'X') ) {
   isExit = 1;
  }
 }
 App_Interrupt_DeInit();
}

/* Print Welcome menu by Polling mode */
static void Print_Menu_Polling(void)
{
 Chip_UART_Send(LPC_UART, uartPolling_menu1, sizeof(uartPolling_menu1), BLOCKING);
 Chip_UART_Send(LPC_UART, uartPolling_menu2, sizeof(uartPolling_menu2), BLOCKING);
 Chip_UART_Send(LPC_UART, uartPolling_menu5, sizeof(uartPolling_menu5), BLOCKING);
}

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

void DMA_IRQHandler(void)
{
 uint8_t dmaChannelNum;
 if (isDMATx) {
  dmaChannelNum = dmaChannelNumTx;
 }
 else {
  dmaChannelNum = dmaChannelNumRx;
 }
 if (Chip_DMA_Interrupt(LPC_GPDMA, dmaChannelNum) == SUCCESS) {
  channelTC++;
 }
 else {
  channelTCErr++;
 }
}

void UARTx_IRQHandler(void)
{
 Chip_UART_Interrupt_Handler(LPC_UART);
}

int main(void)
{
 FlagStatus exitflag;
 uint8_t buffer[10];
 int ret = 0;
 uint32_t len;

 /* UART FIFO configuration Struct variable */
 UART_FIFO_CFG_T UARTFIFOConfigStruct;
 /* Auto baudrate configuration structure */
 UART_AB_CFG_T ABConfig;

 Board_Init();
 Board_UART_Init(LPC_UART);

#if (UARTNum != 0)
 Chip_UART_Init(LPC_UART);
 Chip_UART_SetBaud(LPC_UART, 115200);
 Chip_UART_ConfigData(LPC_UART, UART_DATABIT_8, UART_PARITY_NONE, UART_STOPBIT_1); /* Default 8-N-1 */

 /* Enable UART Transmit */
 Chip_UART_TxCmd(LPC_UART, ENABLE);
#endif

 Chip_UART_FIFOConfigStructInit(LPC_UART, &UARTFIFOConfigStruct);

 /* Enable DMA mode in UART */
 UARTFIFOConfigStruct.FIFO_DMAMode = ENABLE;
 /* Initialize FIFO for UART0 peripheral */
 Chip_UART_FIFOConfig(LPC_UART, &UARTFIFOConfigStruct);

 /* Enable UART End of Auto baudrate interrupt */
 Chip_UART_IntConfig(LPC_UART, UART_INTCFG_ABEO, ENABLE);
 /* Enable UART Auto baudrate timeout interrupt */
 Chip_UART_IntConfig(LPC_UART, UART_INTCFG_ABTO, ENABLE);

 /* preemption = 1, sub-priority = 1 */
 NVIC_SetPriority(UARTx_IRQn, 1);
 /* Enable Interrupt for UART0 channel */
 NVIC_EnableIRQ(UARTx_IRQn);

 /* ---------------------- Auto baud rate section ----------------------- */
 /* Configure Auto baud rate mode */
 ABConfig.ABMode = UART_AUTOBAUD_MODE0;
 ABConfig.AutoRestart = ENABLE;

 /* Start auto baudrate mode */
 Chip_UART_ABCmd(LPC_UART, &ABConfig, ENABLE);

 /* Loop until auto baudrate mode complete */
 while (Chip_UART_GetABEOStatus(LPC_UART) == RESET) {}

 Chip_UART_Send(LPC_UART, uartABComplete, sizeof(uartABComplete), BLOCKING);

 /* Disable UART Interrupt */
 NVIC_DisableIRQ(UARTx_IRQn);

 /* Print welcome screen */
 Print_Menu_Polling();

 exitflag = RESET;
 /* Read some data from the buffer */
 while (exitflag == RESET) {
  len = 0;
  while (len == 0) {
   len = Chip_UART_Receive(LPC_UART, buffer, 1, NONE_BLOCKING);
  }
  if (buffer[0] == 27) {
   /* ESC key, set exit flag */
   Chip_UART_Send(LPC_UART, uartPolling_menu3, sizeof(uartPolling_menu3), BLOCKING);
   ret = -1;
   exitflag = SET;
  }
  else if (buffer[0] == 'c') {
   Chip_UART_Send(LPC_UART, uartPolling_menu4, sizeof(uartPolling_menu4), BLOCKING);
   len = 0;
   while (len == 0) {
    len = Chip_UART_Receive(LPC_UART, buffer, sizeof(buffer), NONE_BLOCKING);
    if ((buffer[0] != '1') && (buffer[0] != '2') && (buffer[0] != '3')) {
     len = 0;
    }
   }
   switch (buffer[0]) {
   case '1':  /* Polling Mode */
    Chip_UART_Send(LPC_UART, uartPolling_menu5, sizeof(uartPolling_menu5), BLOCKING);
    break;

   case '2':  /* Interrupt Mode */
    ret = 2;
    /* Exitflag = SET; */
    App_Interrupt_Test();
    Print_Menu_Polling();
    break;

   case '3':  /* DMA mode */
    ret = 3;
    App_DMA_Test();
    Print_Menu_Polling();
    break;
   }
  }
 }

 /* Wait for current transmission complete - THR must be empty */
 while (Chip_UART_CheckBusy(LPC_UART) == SET) {}

 /* DeInitialize UART0 peripheral */
 Chip_UART_DeInit(LPC_UART);

 return ret;
}