MarlinFirmware/Marlin/src/HAL/HAL_LPC1768/SoftwareSerial.h

/*
 * SoftwareSerial.h (formerly NewSoftSerial.h)
 *
 * Multi-instance software serial library for Arduino/Wiring
 * -- Interrupt-driven receive and other improvements by ladyada
 *    (http://ladyada.net)
 * -- Tuning, circular buffer, derivation from class Print/Stream,
 *    multi-instance support, porting to 8MHz processors,
 *    various optimizations, PROGMEM delay tables, inverse logic and
 *    direct port writing by Mikal Hart (http://www.arduiniana.org)
 * -- Pin change interrupt macros by Paul Stoffregen (http://www.pjrc.com)
 * -- 20MHz processor support by Garrett Mace (http://www.macetech.com)
 * -- ATmega1280/2560 support by Brett Hagman (http://www.roguerobotics.com/)
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * The latest version of this library can always be found at
 * http://arduiniana.org.
 */

#ifndef SOFTWARESERIAL_H
#define SOFTWARESERIAL_H

#include "arduino.h"
#include <stdint.h>
//#include "serial.h"
#include <Stream.h>
#include <Print.h>

/******************************************************************************
* Definitions
******************************************************************************/

#define _SS_MAX_RX_BUFF 64 // RX buffer size

class SoftwareSerial : public Stream
{
private:
  // per object data
  pin_t _receivePin;
  pin_t _transmitPin;
//  uint32_t _receiveBitMask; // for rx interrupts
  uint32_t _receivePort;
  uint32_t _receivePortPin;


  // Expressed as 4-cycle delays (must never be 0!)
  uint16_t _rx_delay_centering;
  uint16_t _rx_delay_intrabit;
  uint16_t _rx_delay_stopbit;
  uint16_t _tx_delay;

  uint16_t _buffer_overflow:1;
  uint16_t _inverse_logic:1;

  // static data
  static unsigned char _receive_buffer[_SS_MAX_RX_BUFF];
  static volatile uint8_t _receive_buffer_tail;
  static volatile uint8_t _receive_buffer_head;
  static SoftwareSerial *active_object;

  // private methods
  void recv();
  uint32_t rx_pin_read();
  void tx_pin_write(uint8_t pin_state);
  void setTX(pin_t transmitPin);
  void setRX(pin_t receivePin);
  void setRxIntMsk(bool enable);

  // private static method for timing
  static inline void tunedDelay(uint32_t delay);

public:
  // public methods

  SoftwareSerial(pin_t receivePin, pin_t transmitPin, bool inverse_logic = false);
  ~SoftwareSerial();
  void begin(long speed);
  bool listen();
  void end();
  bool isListening() { return this == active_object; }
  bool stopListening();
  bool overflow() { bool ret = _buffer_overflow; if (ret) _buffer_overflow = false; return ret; }
  int peek();

  virtual size_t write(uint8_t byte);
  virtual int read();
  virtual int available();
  virtual void flush();
  operator bool() { return true; }

  using Print::write;
  //using HalSerial::write;

  // public only for easy access by interrupt handlers
  static inline void handle_interrupt() __attribute__((__always_inline__));
};

// Arduino 0012 workaround
#undef int
#undef char
#undef long
#undef byte
#undef float
#undef abs
#undef round

#endif // SOFTWARESERIAL_H