serial.h

/*
  serial.c - Low level functions for sending and recieving bytes via the serial port
  Part of Grbl

   The MIT License (MIT)

  GRBL(tm) - Embedded CNC g-code interpreter and motion-controller
  Copyright (c) 2009-2011 Simen Svale Skogsrud
  Copyright (c) 2011-2013 Sungeun K. Jeon

  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:

  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  THE SOFTWARE.
*/

/* This code was initially inspired by the wiring_serial module by David A. Mellis which
   used to be a part of the Arduino project. */

#ifndef serial_h
#define serial_h

#include "nuts_bolts.h"

#ifndef RX_BUFFER_SIZE
  #error
  #define RX_BUFFER_SIZE 128
#endif
#ifndef TX_BUFFER_SIZE
  #error
  #define TX_BUFFER_SIZE 64
#endif

#define SERIAL_NO_DATA 0xff

#ifdef ENABLE_XONXOFF
  #define RX_BUFFER_FULL 96 // XOFF high watermark
  #define RX_BUFFER_LOW 64 // XON low watermark
  #define SEND_XOFF 1
  #define SEND_XON 2
  #define XOFF_SENT 3
  #define XON_SENT 4
  #define XOFF_CHAR 0x13
  #define XON_CHAR 0x11
#endif

void serial_init();

void serial_write(uint8_t data);

uint8_t serial_read();

// Reset and empty data in read buffer. Used by e-stop and reset.
void serial_reset_read_buffer();

#endif