libmodbus/src/modbus-rtu-private.h

/*
 * Copyright © 2001-2010 Stéphane Raimbault <stephane.raimbault@gmail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser 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 Lesser Public License for more details.
 *
 * You should have received a copy of the GNU Lesser Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef _MODBUS_RTU_PRIVATE_H_
#define _MODBUS_RTU_PRIVATE_H_

#define _MODBUS_RTU_HEADER_LENGTH      1
#define _MODBUS_RTU_PRESET_REQ_LENGTH  6
#define _MODBUS_RTU_PRESET_RSP_LENGTH  2

#define _MODBUS_RTU_CHECKSUM_LENGTH    2

typedef struct _modbus_rtu {
    /* Device: "/dev/ttyS0", "/dev/ttyUSB0" or "/dev/tty.USA19*" on Mac OS X for
       KeySpan USB<->Serial adapters this string had to be made bigger on OS X
       as the directory+file name was bigger than 19 bytes. Making it 67 bytes
       for now, but OS X does support 256 byte file names. May become a problem
       in the future. */
#ifdef __APPLE_CC__
    char device[64];
#else
    char device[16];
#endif
    /* Bauds: 9600, 19200, 57600, 115200, etc */
    int baud;
    /* Data bit */
    uint8_t data_bit;
    /* Stop bit */
    uint8_t stop_bit;
    /* Parity: 'N', 'O', 'E' */
    char parity;
    /* Save old termios settings */
    struct termios old_tios;
} modbus_rtu_t;

#endif /* _MODBUS_RTU_PRIVATE_H_ */