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/*

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 * Copyright (c) 2001,2016 Mario de Sousa (msousa@fe.up.pt)

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 *

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 * This file is part of the Modbus library for Beremiz and matiec.

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 *

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 * This Modbus library is free software: you can redistribute it and/or modify

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 * it under the terms of the GNU Lesser General Public License as published by

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 * the Free Software Foundation, either version 3 of the License, or

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 * (at your option) any later version.

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 *

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 * This program is distributed in the hope that it will be useful, but

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 * WITHOUT ANY WARRANTY; without even the implied warranty of

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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser 

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 * General Public License for more details.

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 *

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 * You should have received a copy of the GNU Lesser General Public License

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 * along with this Modbus library.  If not, see <http://www.gnu.org/licenses/>.

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 *

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 * This code is made available on the understanding that it will not be

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 * used in safety-critical situations without a full and competent review.

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 */

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#ifndef MODBUS_RTU_PRIVATE_H

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#define MODBUS_RTU_PRIVATE_H

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#include "mb_types.h" /* get the data types */

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#include "mb_util.h"

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/* serial port default configuration... */

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#define DEF_DATA_BITS 8

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#define DEF_STOP_BITS_PAR 1 /* default stop bits if parity is used     */

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#define DEF_STOP_BITS_NOP 2 /* default stop bits if parity is not used */

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#define DEF_BAUD_RATE 9600

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/* Send retries of rtu frames... */

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#define RTU_FRAME_SEND_RETRY 1

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  /* NOTES:

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   *  - the above are the retries at the layer1 level,

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   *    higher layers may decide to retry for themselves!

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   */

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/* Buffer sizes... */

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 /* We use double the maximum frame length for the read buffer,

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  * due to the algorithm used to work around aborted frames.

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  */

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#define RECV_BUFFER_SIZE_SMALL  (MAX_RTU_FRAME_LENGTH + 10)

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#define RECV_BUFFER_SIZE_LARGE  (2 * (MAX_RTU_FRAME_LENGTH))

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/* Frame lengths... */

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 /* The number of bytes in each frame format, excluding CRC.

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  *

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  * BYTE_COUNT_3  denotes that third byte of frame contains the number of bytes;

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  *                 - total number of bytes in frame is

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  *                   BYTE_COUNT_3_HEADER + byte_count

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  * BYTE_COUNT_34 denotes that third+fourth bytes of frame contain the number of bytes;

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  *                 - total number of bytes in frame is

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  *                   BYTE_COUNT_34_HEADER + byte_count

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  * BYTE_COUNT_7  denotes that seventh byte of frame contain the number of bytes;

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  *                 - total number of bytes in frame is

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  *                   BYTE_COUNT_7_HEADER + byte_count

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  * BYTE_COUNT_11 denotes that eleventh byte of frame contain the number of bytes;

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  *                 - total number of bytes in frame is

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  *                   BYTE_COUNT_11_HEADER + byte_count

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  * BYTE_COUNT_U  denotes unknown number of bytes;

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  */

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#define BYTE_COUNT_3_HEADER   3

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#define BYTE_COUNT_34_HEADER  4

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#define BYTE_COUNT_7_HEADER   7

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#define BYTE_COUNT_11_HEADER  11

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#define BYTE_COUNT_3  (-3)

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#define BYTE_COUNT_34 (-34)

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#define BYTE_COUNT_7  (-7)

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#define BYTE_COUNT_11 (-11)

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#define BYTE_COUNT_U  (-128)

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#define MAX_FUNCTION_CODE 0x18

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#define MIN_FRAME_LENGTH       3

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#define EXCEPTION_FRAME_LENGTH 3

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static i8 query_frame_lengths[MAX_FUNCTION_CODE+1] = {

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                /* 0x00 */ 0,             /* unused                    */

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                /* 0x01 */ 6,             /* Read Coil Status          */

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                /* 0x02 */ 6,             /* Read Input Status         */

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                /* 0x03 */ 6,             /* Read Holding Registers    */

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                /* 0x04 */ 6,             /* Read Input Registers      */

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                /* 0x05 */ 6,             /* Force Single Coil         */

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                /* 0x06 */ 6,             /* Preset Single Register    */

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                /* 0x07 */ 2,             /* Read Exception Status     */

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                /* 0x08 */ 4,             /* Diagnostics               */

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                /* 0x09 */ BYTE_COUNT_U,  /* Program 484               */

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                /* 0x0A */ BYTE_COUNT_U,  /* Poll 484                  */

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                /* 0x0B */ 2,             /* Fetch Comm. Event Counter */

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                /* 0x0C */ 2,             /* Fetch Comm. Event Log     */

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                /* 0x0D */ BYTE_COUNT_U,  /* Program Controller        */

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                /* 0x0E */ BYTE_COUNT_U,  /* Poll Controller           */

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                /* 0x0F */ BYTE_COUNT_7,  /* Force Multiple Coils      */

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                /* 0x10 */ BYTE_COUNT_7,  /* Preset Multiple Registers */

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                /* 0x11 */ 2,             /* Report Slave ID           */

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                /* 0x12 */ BYTE_COUNT_U,  /* Program 884/M84           */

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                /* 0x13 */ BYTE_COUNT_U,  /* Reset. Comm. Link         */

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                /* 0x14 */ BYTE_COUNT_3,  /* Read General Reference    */

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                /* 0x15 */ BYTE_COUNT_3,  /* Write General Reference   */

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                /* 0x16 */ 8,             /* Mask Write 4X Register    */

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                /* 0x17 */ BYTE_COUNT_11, /* Read/Write 4x Register    */

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                /* 0x18 */ 4              /* Read FIFO Queue           */

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              };

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static i8 response_frame_lengths[MAX_FUNCTION_CODE+1] = {

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                /* 0x00 */ 0,             /* unused                    */

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                /* 0x01 */ BYTE_COUNT_3,  /* Read Coil Status          */

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                /* 0x02 */ BYTE_COUNT_3,  /* Read Input Status         */

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                /* 0x03 */ BYTE_COUNT_3,  /* Read Holding Registers    */

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                /* 0x04 */ BYTE_COUNT_3,  /* Read Input Registers      */

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                /* 0x05 */ 6,             /* Force Single Coil         */

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                /* 0x06 */ 6,             /* Preset Single Register    */

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                /* 0x07 */ 3,             /* Read Exception Status     */

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                /* 0x08 */ 6,/*see (1)*/  /* Diagnostics               */

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                /* 0x09 */ BYTE_COUNT_U,  /* Program 484               */

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                /* 0x0A */ BYTE_COUNT_U,  /* Poll 484                  */

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                /* 0x0B */ 6,             /* Fetch Comm. Event Counter */

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                /* 0x0C */ BYTE_COUNT_3,  /* Fetch Comm. Event Log     */

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                /* 0x0D */ BYTE_COUNT_U,  /* Program Controller        */

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                /* 0x0E */ BYTE_COUNT_U,  /* Poll Controller           */

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                /* 0x0F */ 6,             /* Force Multiple Coils      */

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                /* 0x10 */ 6,             /* Preset Multiple Registers */

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                /* 0x11 */ BYTE_COUNT_3,  /* Report Slave ID           */

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                /* 0x12 */ BYTE_COUNT_U,  /* Program 884/M84           */

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                /* 0x13 */ BYTE_COUNT_U,  /* Reset. Comm. Link         */

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                /* 0x14 */ BYTE_COUNT_3,  /* Read General Reference    */

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                /* 0x15 */ BYTE_COUNT_3,  /* Write General Reference   */

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                /* 0x16 */ 8,             /* Mask Write 4X Register    */

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                /* 0x17 */ BYTE_COUNT_3,  /* Read/Write 4x Register    */

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                /* 0x18 */ BYTE_COUNT_34  /* Read FIFO Queue           */

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              };

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/* NOTE (1):

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 *    The diagnostic function (0x08) has sub-functions. In particular,

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 *    sub-function 21 (0x15) has two sub-sub-functions. In the very

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 *    particular case of *one* of these sub-sub-functions, the reply

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 *    frame does *not* have a size of 4, but is variable in length

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 *    and includes a byte counter.

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 *    To take this into account in the table would require an extra two

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 *    tables.

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 *    The above length has been hardcoded into the frame_length() function

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 *    (in file modbus_rtu.c)

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 */

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#define FALSE 0

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#define TRUE 1

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#endif  /* MODBUS_RTU_PRIVATE_H */

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