/* * (c) 2001 Mario de Sousa * * Offered to the public under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 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. * * This code is made available on the understanding that it will not be * used in safety-critical situations without a full and competent review. */ #ifndef MODBUS_RTU_PRIVATE_H #define MODBUS_RTU_PRIVATE_H #include /* get the plc data types */ #include "mb_util.h" /* serial port default configuration... */ #define DEF_DATA_BITS 8 #define DEF_STOP_BITS_PAR 1 /* default stop bits if parity is used */ #define DEF_STOP_BITS_NOP 2 /* default stop bits if parity is not used */ #define DEF_BAUD_RATE 9600 /* Send retries of rtu frames... */ #define RTU_FRAME_SEND_RETRY 1 /* NOTES: * - the above are the retries at the layer1 level, * higher layers may decide to retry for themselves! */ /* Buffer sizes... */ /* We use double the maximum frame length for the read buffer, * due to the algorithm used to work around aborted frames. */ #define RECV_BUFFER_SIZE_SMALL (MAX_RTU_FRAME_LENGTH + 10) #define RECV_BUFFER_SIZE_LARGE (2 * MAX_RTU_FRAME_LENGTH) /* Frame lengths... */ /* The number of bytes in each frame format, excluding CRC. * * BYTE_COUNT_3 denotes that third byte of frame contains the number of bytes; * - total number of bytes in frame is * BYTE_COUNT_3_HEADER + byte_count * BYTE_COUNT_34 denotes that third+fourth bytes of frame contain the number of bytes; * - total number of bytes in frame is * BYTE_COUNT_34_HEADER + byte_count * BYTE_COUNT_7 denotes that seventh byte of frame contain the number of bytes; * - total number of bytes in frame is * BYTE_COUNT_7_HEADER + byte_count * BYTE_COUNT_11 denotes that eleventh byte of frame contain the number of bytes; * - total number of bytes in frame is * BYTE_COUNT_11_HEADER + byte_count * BYTE_COUNT_U denotes unknown number of bytes; */ #define BYTE_COUNT_3_HEADER 3 #define BYTE_COUNT_34_HEADER 4 #define BYTE_COUNT_7_HEADER 7 #define BYTE_COUNT_11_HEADER 11 #define BYTE_COUNT_3 (-3) #define BYTE_COUNT_34 (-34) #define BYTE_COUNT_7 (-7) #define BYTE_COUNT_11 (-11) #define BYTE_COUNT_U (-128) #define MAX_FUNCTION_CODE 0x18 #define MIN_FRAME_LENGTH 3 #define EXCEPTION_FRAME_LENGTH 3 static i8 query_frame_lengths[MAX_FUNCTION_CODE+1] = { /* 0x00 */ 0, /* unused */ /* 0x01 */ 6, /* Read Coil Status */ /* 0x02 */ 6, /* Read Input Status */ /* 0x03 */ 6, /* Read Holding Registers */ /* 0x04 */ 6, /* Read Input Registers */ /* 0x05 */ 6, /* Force Single Coil */ /* 0x06 */ 6, /* Preset Single Register */ /* 0x07 */ 2, /* Read Exception Status */ /* 0x08 */ 4, /* Diagnostics */ /* 0x09 */ BYTE_COUNT_U, /* Program 484 */ /* 0x0A */ BYTE_COUNT_U, /* Poll 484 */ /* 0x0B */ 2, /* Fetch Comm. Event Counter */ /* 0x0C */ 2, /* Fetch Comm. Event Log */ /* 0x0D */ BYTE_COUNT_U, /* Program Controller */ /* 0x0E */ BYTE_COUNT_U, /* Poll Controller */ /* 0x0F */ BYTE_COUNT_7, /* Force Multiple Coils */ /* 0x10 */ BYTE_COUNT_7, /* Preset Multiple Registers */ /* 0x11 */ 2, /* Report Slave ID */ /* 0x12 */ BYTE_COUNT_U, /* Program 884/M84 */ /* 0x13 */ BYTE_COUNT_U, /* Reset. Comm. Link */ /* 0x14 */ BYTE_COUNT_3, /* Read General Reference */ /* 0x15 */ BYTE_COUNT_3, /* Write General Reference */ /* 0x16 */ 8, /* Mask Write 4X Register */ /* 0x17 */ BYTE_COUNT_11, /* Read/Write 4x Register */ /* 0x18 */ 4 /* Read FIFO Queue */ }; static i8 response_frame_lengths[MAX_FUNCTION_CODE+1] = { /* 0x00 */ 0, /* unused */ /* 0x01 */ BYTE_COUNT_3, /* Read Coil Status */ /* 0x02 */ BYTE_COUNT_3, /* Read Input Status */ /* 0x03 */ BYTE_COUNT_3, /* Read Holding Registers */ /* 0x04 */ BYTE_COUNT_3, /* Read Input Registers */ /* 0x05 */ 6, /* Force Single Coil */ /* 0x06 */ 6, /* Preset Single Register */ /* 0x07 */ 3, /* Read Exception Status */ /* 0x08 */ 6,/*see (1)*/ /* Diagnostics */ /* 0x09 */ BYTE_COUNT_U, /* Program 484 */ /* 0x0A */ BYTE_COUNT_U, /* Poll 484 */ /* 0x0B */ 6, /* Fetch Comm. Event Counter */ /* 0x0C */ BYTE_COUNT_3, /* Fetch Comm. Event Log */ /* 0x0D */ BYTE_COUNT_U, /* Program Controller */ /* 0x0E */ BYTE_COUNT_U, /* Poll Controller */ /* 0x0F */ 6, /* Force Multiple Coils */ /* 0x10 */ 6, /* Preset Multiple Registers */ /* 0x11 */ BYTE_COUNT_3, /* Report Slave ID */ /* 0x12 */ BYTE_COUNT_U, /* Program 884/M84 */ /* 0x13 */ BYTE_COUNT_U, /* Reset. Comm. Link */ /* 0x14 */ BYTE_COUNT_3, /* Read General Reference */ /* 0x15 */ BYTE_COUNT_3, /* Write General Reference */ /* 0x16 */ 8, /* Mask Write 4X Register */ /* 0x17 */ BYTE_COUNT_3, /* Read/Write 4x Register */ /* 0x18 */ BYTE_COUNT_34 /* Read FIFO Queue */ }; /* NOTE (1): * The diagnostic function (0x08) has sub-functions. In particular, * sub-function 21 (0x15) has two sub-sub-functions. In the very * particular case of *one* of these sub-sub-functions, the reply * frame does *not* have a size of 4, but is variable in length * and includes a byte counter. * To take this into account in the table would require an extra two * tables. * The above length has been hardcoded into the frame_length() function * (in file modbus_rtu.c) */ #define FALSE 0 #define TRUE 1 #endif /* MODBUS_RTU_PRIVATE_H */