marlin/Marlin/src/HAL/HAL_LPC1768/HardwareSerial.cpp

/**
 * Marlin 3D Printer Firmware
 * Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
 * Based on Sprinter and grbl.
 * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifdef TARGET_LPC1768

#include "../../inc/MarlinConfig.h"
#include "HardwareSerial.h"

HardwareSerial Serial = HardwareSerial(LPC_UART0);
HardwareSerial Serial1 = HardwareSerial((LPC_UART_TypeDef *) LPC_UART1);
HardwareSerial Serial2 = HardwareSerial(LPC_UART2);
HardwareSerial Serial3 = HardwareSerial(LPC_UART3);

void HardwareSerial::begin(uint32_t baudrate) {

  UART_CFG_Type UARTConfigStruct;
  PINSEL_CFG_Type PinCfg;
  UART_FIFO_CFG_Type FIFOConfig;

  if (UARTx == LPC_UART0) {
    /*
    * Initialize UART0 pin connect
    */
    PinCfg.Funcnum = 1;
    PinCfg.OpenDrain = 0;
    PinCfg.Pinmode = 0;
    PinCfg.Pinnum = 2;
    PinCfg.Portnum = 0;
    PINSEL_ConfigPin(&PinCfg);
    PinCfg.Pinnum = 3;
    PINSEL_ConfigPin(&PinCfg);
  }
  else if ((LPC_UART1_TypeDef *) UARTx == LPC_UART1) {
    /*
    * Initialize UART1 pin connect
    */
    PinCfg.Funcnum = 1;
    PinCfg.OpenDrain = 0;
    PinCfg.Pinmode = 0;
    PinCfg.Pinnum = 15;
    PinCfg.Portnum = 0;
    PINSEL_ConfigPin(&PinCfg);
    PinCfg.Pinnum = 16;
    PINSEL_ConfigPin(&PinCfg);
  }
  else if (UARTx == LPC_UART2) {
    /*
    * Initialize UART2 pin connect
    */
    PinCfg.Funcnum = 1;
    PinCfg.OpenDrain = 0;
    PinCfg.Pinmode = 0;
    PinCfg.Pinnum = 10;
    PinCfg.Portnum = 0;
    PINSEL_ConfigPin(&PinCfg);
    PinCfg.Pinnum = 11;
    PINSEL_ConfigPin(&PinCfg);
  }
  else if (UARTx == LPC_UART3) {
    /*
    * Initialize UART2 pin connect
    */
    PinCfg.Funcnum = 1;
    PinCfg.OpenDrain = 0;
    PinCfg.Pinmode = 0;
    PinCfg.Pinnum = 0;
    PinCfg.Portnum = 0;
    PINSEL_ConfigPin(&PinCfg);
    PinCfg.Pinnum = 1;
    PINSEL_ConfigPin(&PinCfg);
  }

	/* Initialize UART Configuration parameter structure to default state:
	 * Baudrate = 9600bps
	 * 8 data bit
	 * 1 Stop bit
	 * None parity
	 */
	UART_ConfigStructInit(&UARTConfigStruct);

	// Re-configure baudrate
	UARTConfigStruct.Baud_rate = baudrate;

	// Initialize eripheral with given to corresponding parameter
  UART_Init(UARTx, &UARTConfigStruct);

  // Enable and reset the TX and RX FIFOs
  UART_FIFOConfigStructInit(&FIFOConfig);
  UART_FIFOConfig(UARTx, &FIFOConfig);

	// Enable UART Transmit
  UART_TxCmd(UARTx, ENABLE);

  // Configure Interrupts
  UART_IntConfig(UARTx, UART_INTCFG_RBR, ENABLE);
  UART_IntConfig(UARTx, UART_INTCFG_RLS, ENABLE);

  if (UARTx == LPC_UART0)
    NVIC_EnableIRQ(UART0_IRQn);
  else if ((LPC_UART1_TypeDef *) UARTx == LPC_UART1)
    NVIC_EnableIRQ(UART1_IRQn);
  else if (UARTx == LPC_UART2)
    NVIC_EnableIRQ(UART2_IRQn);
  else if (UARTx == LPC_UART3)
    NVIC_EnableIRQ(UART3_IRQn);

  RxQueueWritePos = RxQueueReadPos = 0;
  #if TX_BUFFER_SIZE > 0
    TxQueueWritePos = TxQueueReadPos = 0;
  #endif
}

int HardwareSerial::peek() {
  int byte = -1;

  /* Temporarily lock out UART receive interrupts during this read so the UART receive
     interrupt won't cause problems with the index values */
  UART_IntConfig(UARTx, UART_INTCFG_RBR, DISABLE);

  if (RxQueueReadPos != RxQueueWritePos)
    byte = RxBuffer[RxQueueReadPos];

  /* Re-enable UART interrupts */
  UART_IntConfig(UARTx, UART_INTCFG_RBR, ENABLE);

  return byte;
}

int HardwareSerial::read() {
  int byte = -1;

  /* Temporarily lock out UART receive interrupts during this read so the UART receive
     interrupt won't cause problems with the index values */
  UART_IntConfig(UARTx, UART_INTCFG_RBR, DISABLE);

  if (RxQueueReadPos != RxQueueWritePos) {
    byte = RxBuffer[RxQueueReadPos];
    RxQueueReadPos = (RxQueueReadPos + 1) % RX_BUFFER_SIZE;
  }

  /* Re-enable UART interrupts */
  UART_IntConfig(UARTx, UART_INTCFG_RBR, ENABLE);

  return byte;
}

size_t HardwareSerial::write(uint8_t send) {
  #if TX_BUFFER_SIZE > 0
    size_t   bytes = 0;
    uint32_t fifolvl = 0;

    /* If the Tx Buffer is full, wait for space to clear */
    if ((TxQueueWritePos+1) % TX_BUFFER_SIZE == TxQueueReadPos) flushTX();

    /* Temporarily lock out UART transmit interrupts during this read so the UART transmit interrupt won't
       cause problems with the index values */
    UART_IntConfig(UARTx, UART_INTCFG_THRE, DISABLE);

    /* LPC17xx.h incorrectly defines FIFOLVL as a uint8_t, when it's actually a 32-bit register */
    if ((LPC_UART1_TypeDef *) UARTx == LPC_UART1)
      fifolvl = *(reinterpret_cast<volatile uint32_t *>(&((LPC_UART1_TypeDef *) UARTx)->FIFOLVL));
    else
      fifolvl = *(reinterpret_cast<volatile uint32_t *>(&UARTx->FIFOLVL));

    /* If the queue is empty and there's space in the FIFO, immediately send the byte */
    if (TxQueueWritePos == TxQueueReadPos && fifolvl < UART_TX_FIFO_SIZE) {
      bytes = UART_Send(UARTx, &send, 1, BLOCKING);
    }
    /* Otherwiise, write the byte to the transmit buffer */
    else if ((TxQueueWritePos+1) % TX_BUFFER_SIZE != TxQueueReadPos) {
      TxBuffer[TxQueueWritePos] = send;
      TxQueueWritePos = (TxQueueWritePos+1) % TX_BUFFER_SIZE;
      bytes++;
    }

    /* Re-enable the TX Interrupt */
    UART_IntConfig(UARTx, UART_INTCFG_THRE, ENABLE);

    return bytes;
  #else
    return UART_Send(UARTx, &send, 1, BLOCKING);
  #endif
}

#if TX_BUFFER_SIZE > 0
  void HardwareSerial::flushTX() {
    /* Wait for the tx buffer and FIFO to drain */
    while (TxQueueWritePos != TxQueueReadPos && UART_CheckBusy(UARTx) == SET);
  }
#endif

int HardwareSerial::available() {
  return (RxQueueWritePos + RX_BUFFER_SIZE - RxQueueReadPos) % RX_BUFFER_SIZE;
}

void HardwareSerial::flush() {
  RxQueueWritePos = 0;
  RxQueueReadPos = 0;
}

void HardwareSerial::printf(const char *format, ...) {
  char RxBuffer[256];
  va_list vArgs;
  va_start(vArgs, format);
  int length = vsnprintf(RxBuffer, 256, format, vArgs);
  va_end(vArgs);
  if (length > 0 && length < 256) {
    for (int i = 0; i < length; ++i)
      write(RxBuffer[i]);
  }
}

void HardwareSerial::IRQHandler() {
  uint32_t IIRValue;
  uint8_t LSRValue, byte;

  IIRValue = UART_GetIntId(UARTx);
  IIRValue &= UART_IIR_INTID_MASK;		/* check bit 1~3, interrupt identification */

  if ( IIRValue == UART_IIR_INTID_RLS )		/* Receive Line Status */
  {
    LSRValue = UART_GetLineStatus(UARTx);

    /* Receive Line Status */
    if ( LSRValue & (UART_LSR_OE|UART_LSR_PE|UART_LSR_FE|UART_LSR_RXFE|UART_LSR_BI) )
    {
      /* There are errors or break interrupt */
      /* Read LSR will clear the interrupt */
      Status = LSRValue;
      byte = UART_ReceiveByte(UARTx);		/* Dummy read on RX to clear
                                           interrupt, then bail out */
      return;
    }
  }

  if ( IIRValue == UART_IIR_INTID_RDA )	/* Receive Data Available */
  {
    /* Clear the FIFO */
    while ( UART_Receive(UARTx, &byte, 1, NONE_BLOCKING) ) {
      if ((RxQueueWritePos+1) % RX_BUFFER_SIZE != RxQueueReadPos)
      {
        RxBuffer[RxQueueWritePos] = byte;
        RxQueueWritePos = (RxQueueWritePos+1) % RX_BUFFER_SIZE;
      }
      else
        break;
    }
  }
  else if ( IIRValue == UART_IIR_INTID_CTI )	/* Character timeout indicator */
  {
    /* Character Time-out indicator */
    Status |= 0x100;		/* Bit 9 as the CTI error */
  }

  #if TX_BUFFER_SIZE > 0
    if (IIRValue == UART_IIR_INTID_THRE) {
      /* Disable THRE interrupt */
      UART_IntConfig(UARTx, UART_INTCFG_THRE, DISABLE);

      /* Wait for FIFO buffer empty */
      while (UART_CheckBusy(UARTx) == SET);

      /* Transfer up to UART_TX_FIFO_SIZE bytes of data */
      for (int i = 0; i < UART_TX_FIFO_SIZE && TxQueueWritePos != TxQueueReadPos; i++) {
        /* Move a piece of data into the transmit FIFO */
        if (UART_Send(UARTx, &TxBuffer[TxQueueReadPos], 1, NONE_BLOCKING))
          TxQueueReadPos = (TxQueueReadPos+1) % TX_BUFFER_SIZE;
        else
          break;
      }

      /* If there is no more data to send, disable the transmit interrupt - else enable it or keep it enabled */
      if (TxQueueWritePos == TxQueueReadPos)
        UART_IntConfig(UARTx, UART_INTCFG_THRE, DISABLE);
      else
        UART_IntConfig(UARTx, UART_INTCFG_THRE, ENABLE);
    }
  #endif
}

#ifdef __cplusplus
extern "C" {
#endif

/*****************************************************************************
** Function name:		UART0_IRQHandler
**
** Descriptions:		UART0 interrupt handler
**
** parameters:			None
** Returned value:		None
**
*****************************************************************************/
void UART0_IRQHandler (void)
{
  Serial.IRQHandler();
}

/*****************************************************************************
** Function name:		UART1_IRQHandler
**
** Descriptions:		UART1 interrupt handler
**
** parameters:			None
** Returned value:		None
**
*****************************************************************************/
void UART1_IRQHandler (void)
{
  Serial1.IRQHandler();
}

/*****************************************************************************
** Function name:		UART2_IRQHandler
**
** Descriptions:		UART2 interrupt handler
**
** parameters:			None
** Returned value:		None
**
*****************************************************************************/
void UART2_IRQHandler (void)
{
  Serial2.IRQHandler();
}

/*****************************************************************************
** Function name:		UART3_IRQHandler
**
** Descriptions:		UART3 interrupt handler
**
** parameters:			None
** Returned value:		None
**
*****************************************************************************/
void UART3_IRQHandler (void)
{
  Serial3.IRQHandler();
}

#ifdef __cplusplus
}
#endif

#endif // TARGET_LPC1768