src/modbus.h

   1 /*
   2  * Copyright © 2001-2013 Stéphane Raimbault <stephane.raimbault@gmail.com>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 #ifndef _MODBUS_H_
  20 #define _MODBUS_H_
  21
  22 /* Add this for macros that defined unix flavor */
  23 #if (defined(__unix__) || defined(unix)) && !defined(USG)
  24 #include <sys/param.h>
  25 #endif
  26
  27 #ifndef _MSC_VER
  28 #include <stdint.h>
  29 #else
  30 #include "stdint.h"
  31 #endif
  32
  33 #include "modbus-version.h"
  34
  35 #if defined(_MSC_VER)
  36 # if defined(DLLBUILD)
  37 /* define DLLBUILD when building the DLL */
  38 #  define MODBUS_API __declspec(dllexport)
  39 # else
  40 #  define MODBUS_API __declspec(dllimport)
  41 # endif
  42 #else
  43 # define MODBUS_API
  44 #endif
  45
  46 #ifdef  __cplusplus
  47 # define MODBUS_BEGIN_DECLS  extern "C" {
  48 # define MODBUS_END_DECLS    }
  49 #else
  50 # define MODBUS_BEGIN_DECLS
  51 # define MODBUS_END_DECLS
  52 #endif
  53
  54 MODBUS_BEGIN_DECLS
  55
  56 #ifndef FALSE
  57 #define FALSE 0
  58 #endif
  59
  60 #ifndef TRUE
  61 #define TRUE 1
  62 #endif
  63
  64 #ifndef OFF
  65 #define OFF 0
  66 #endif
  67
  68 #ifndef ON
  69 #define ON 1
  70 #endif
  71
  72 /* Modbus function codes */
  73 #define MODBUS_FC_READ_COILS                0x01
  74 #define MODBUS_FC_READ_DISCRETE_INPUTS      0x02
  75 #define MODBUS_FC_READ_HOLDING_REGISTERS    0x03
  76 #define MODBUS_FC_READ_INPUT_REGISTERS      0x04
  77 #define MODBUS_FC_WRITE_SINGLE_COIL         0x05
  78 #define MODBUS_FC_WRITE_SINGLE_REGISTER     0x06
  79 #define MODBUS_FC_READ_EXCEPTION_STATUS     0x07
  80 #define MODBUS_FC_WRITE_MULTIPLE_COILS      0x0F
  81 #define MODBUS_FC_WRITE_MULTIPLE_REGISTERS  0x10
  82 #define MODBUS_FC_REPORT_SLAVE_ID           0x11
  83 #define MODBUS_FC_MASK_WRITE_REGISTER       0x16
  84 #define MODBUS_FC_WRITE_AND_READ_REGISTERS  0x17
  85
  86 #define MODBUS_BROADCAST_ADDRESS    0
  87
  88 /* Modbus_Application_Protocol_V1_1b.pdf (chapter 6 section 1 page 12)
  89  * Quantity of Coils to read (2 bytes): 1 to 2000 (0x7D0)
  90  * (chapter 6 section 11 page 29)
  91  * Quantity of Coils to write (2 bytes): 1 to 1968 (0x7B0)
  92  */
  93 #define MODBUS_MAX_READ_BITS              2000
  94 #define MODBUS_MAX_WRITE_BITS             1968
  95
  96 /* Modbus_Application_Protocol_V1_1b.pdf (chapter 6 section 3 page 15)
  97  * Quantity of Registers to read (2 bytes): 1 to 125 (0x7D)
  98  * (chapter 6 section 12 page 31)
  99  * Quantity of Registers to write (2 bytes) 1 to 123 (0x7B)
 100  * (chapter 6 section 17 page 38)
 101  * Quantity of Registers to write in R/W registers (2 bytes) 1 to 121 (0x79)
 102  */
 103 #define MODBUS_MAX_READ_REGISTERS          125
 104 #define MODBUS_MAX_WRITE_REGISTERS         123
 105 #define MODBUS_MAX_WR_WRITE_REGISTERS      121
 106 #define MODBUS_MAX_WR_READ_REGISTERS       125
 107
 108 /* Random number to avoid errno conflicts */
 109 #define MODBUS_ENOBASE 112345678
 110
 111 /* Protocol exceptions */
 112 enum {
 113     MODBUS_EXCEPTION_ILLEGAL_FUNCTION = 0x01,
 114     MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS,
 115     MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE,
 116     MODBUS_EXCEPTION_SLAVE_OR_SERVER_FAILURE,
 117     MODBUS_EXCEPTION_ACKNOWLEDGE,
 118     MODBUS_EXCEPTION_SLAVE_OR_SERVER_BUSY,
 119     MODBUS_EXCEPTION_NEGATIVE_ACKNOWLEDGE,
 120     MODBUS_EXCEPTION_MEMORY_PARITY,
 121     MODBUS_EXCEPTION_NOT_DEFINED,
 122     MODBUS_EXCEPTION_GATEWAY_PATH,
 123     MODBUS_EXCEPTION_GATEWAY_TARGET,
 124     MODBUS_EXCEPTION_MAX
 125 };
 126
 127 #define EMBXILFUN  (MODBUS_ENOBASE + MODBUS_EXCEPTION_ILLEGAL_FUNCTION)
 128 #define EMBXILADD  (MODBUS_ENOBASE + MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS)
 129 #define EMBXILVAL  (MODBUS_ENOBASE + MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE)
 130 #define EMBXSFAIL  (MODBUS_ENOBASE + MODBUS_EXCEPTION_SLAVE_OR_SERVER_FAILURE)
 131 #define EMBXACK    (MODBUS_ENOBASE + MODBUS_EXCEPTION_ACKNOWLEDGE)
 132 #define EMBXSBUSY  (MODBUS_ENOBASE + MODBUS_EXCEPTION_SLAVE_OR_SERVER_BUSY)
 133 #define EMBXNACK   (MODBUS_ENOBASE + MODBUS_EXCEPTION_NEGATIVE_ACKNOWLEDGE)
 134 #define EMBXMEMPAR (MODBUS_ENOBASE + MODBUS_EXCEPTION_MEMORY_PARITY)
 135 #define EMBXGPATH  (MODBUS_ENOBASE + MODBUS_EXCEPTION_GATEWAY_PATH)
 136 #define EMBXGTAR   (MODBUS_ENOBASE + MODBUS_EXCEPTION_GATEWAY_TARGET)
 137
 138 /* Native libmodbus error codes */
 139 #define EMBBADCRC  (EMBXGTAR + 1)
 140 #define EMBBADDATA (EMBXGTAR + 2)
 141 #define EMBBADEXC  (EMBXGTAR + 3)
 142 #define EMBUNKEXC  (EMBXGTAR + 4)
 143 #define EMBMDATA   (EMBXGTAR + 5)
 144 #define EMBBADSLAVE (EMBXGTAR + 6)
 145
 146 extern const unsigned int libmodbus_version_major;
 147 extern const unsigned int libmodbus_version_minor;
 148 extern const unsigned int libmodbus_version_micro;
 149
 150 typedef struct _modbus modbus_t;
 151
 152 typedef struct {
 153     int nb_bits;
 154     int nb_input_bits;
 155     int nb_input_registers;
 156     int nb_registers;
 157     uint8_t *tab_bits;
 158     uint8_t *tab_input_bits;
 159     uint16_t *tab_input_registers;
 160     uint16_t *tab_registers;
 161 } modbus_mapping_t;
 162
 163 typedef enum
 164 {
 165     MODBUS_ERROR_RECOVERY_NONE          = 0,
 166     MODBUS_ERROR_RECOVERY_LINK          = (1<<1),
 167     MODBUS_ERROR_RECOVERY_PROTOCOL      = (1<<2),
 168 } modbus_error_recovery_mode;
 169
 170 MODBUS_API int modbus_set_slave(modbus_t* ctx, int slave);
 171 MODBUS_API int modbus_set_error_recovery(modbus_t *ctx, modbus_error_recovery_mode error_recovery);
 172 MODBUS_API int modbus_set_socket(modbus_t *ctx, int s);
 173 MODBUS_API int modbus_get_socket(modbus_t *ctx);
 174
 175 MODBUS_API int modbus_get_response_timeout(modbus_t *ctx, long *to_sec, long *to_usec);
 176 MODBUS_API int modbus_set_response_timeout(modbus_t *ctx, long to_sec, long to_usec);
 177
 178 MODBUS_API int modbus_get_byte_timeout(modbus_t *ctx, long *to_sec, long *to_usec);
 179 MODBUS_API int modbus_set_byte_timeout(modbus_t *ctx, long to_sec, long to_usec);
 180
 181 MODBUS_API int modbus_get_header_length(modbus_t *ctx);
 182
 183 MODBUS_API int modbus_connect(modbus_t *ctx);
 184 MODBUS_API void modbus_close(modbus_t *ctx);
 185
 186 MODBUS_API void modbus_free(modbus_t *ctx);
 187
 188 MODBUS_API int modbus_flush(modbus_t *ctx);
 189 MODBUS_API int modbus_set_debug(modbus_t *ctx, int flag);
 190
 191 MODBUS_API const char *modbus_strerror(int errnum);
 192
 193 MODBUS_API int modbus_read_bits(modbus_t *ctx, int addr, int nb, uint8_t *dest);
 194 MODBUS_API int modbus_read_input_bits(modbus_t *ctx, int addr, int nb, uint8_t *dest);
 195 MODBUS_API int modbus_read_registers(modbus_t *ctx, int addr, int nb, uint16_t *dest);
 196 MODBUS_API int modbus_read_input_registers(modbus_t *ctx, int addr, int nb, uint16_t *dest);
 197 MODBUS_API int modbus_write_bit(modbus_t *ctx, int coil_addr, int status);
 198 MODBUS_API int modbus_write_register(modbus_t *ctx, int reg_addr, int value);
 199 MODBUS_API int modbus_write_bits(modbus_t *ctx, int addr, int nb, const uint8_t *data);
 200 MODBUS_API int modbus_write_registers(modbus_t *ctx, int addr, int nb, const uint16_t *data);
 201 MODBUS_API int modbus_mask_write_register(modbus_t *ctx, int addr, uint16_t and_mask, uint16_t or_mask);
 202 MODBUS_API int modbus_write_and_read_registers(modbus_t *ctx, int write_addr, int write_nb,
 203                                                const uint16_t *src, int read_addr, int read_nb,
 204                                                uint16_t *dest);
 205 MODBUS_API int modbus_report_slave_id(modbus_t *ctx, uint8_t *dest);
 206
 207 MODBUS_API modbus_mapping_t* modbus_mapping_new(int nb_bits, int nb_input_bits,
 208                                             int nb_registers, int nb_input_registers);
 209 MODBUS_API void modbus_mapping_free(modbus_mapping_t *mb_mapping);
 210
 211 MODBUS_API int modbus_send_raw_request(modbus_t *ctx, uint8_t *raw_req, int raw_req_length);
 212
 213 MODBUS_API int modbus_receive(modbus_t *ctx, uint8_t *req);
 214 MODBUS_API int modbus_receive_from(modbus_t *ctx, int sockfd, uint8_t *req);
 215
 216 MODBUS_API int modbus_receive_confirmation(modbus_t *ctx, uint8_t *rsp);
 217
 218 MODBUS_API int modbus_reply(modbus_t *ctx, const uint8_t *req,
 219                             int req_length, modbus_mapping_t *mb_mapping);
 220 MODBUS_API int modbus_reply_exception(modbus_t *ctx, const uint8_t *req,
 221                                       unsigned int exception_code);
 222
 223 /**
 224  * UTILS FUNCTIONS
 225  **/
 226
 227 #define MODBUS_GET_HIGH_BYTE(data) (((data) >> 8) & 0xFF)
 228 #define MODBUS_GET_LOW_BYTE(data) ((data) & 0xFF)
 229 #define MODBUS_GET_INT32_FROM_INT16(tab_int16, index) ((tab_int16[(index)] << 16) + tab_int16[(index) + 1])
 230 #define MODBUS_GET_INT16_FROM_INT8(tab_int8, index) ((tab_int8[(index)] << 8) + tab_int8[(index) + 1])
 231 #define MODBUS_SET_INT16_TO_INT8(tab_int8, index, value) \
 232     do { \
 233         tab_int8[(index)] = (value) >> 8;  \
 234         tab_int8[(index) + 1] = (value) & 0xFF; \
 235     } while (0)
 236
 237 MODBUS_API void modbus_set_bits_from_byte(uint8_t *dest, int idx, const uint8_t value);
 238 MODBUS_API void modbus_set_bits_from_bytes(uint8_t *dest, int idx, unsigned int nb_bits,
 239                                        const uint8_t *tab_byte);
 240 MODBUS_API uint8_t modbus_get_byte_from_bits(const uint8_t *src, int idx, unsigned int nb_bits);
 241 MODBUS_API float modbus_get_float(const uint16_t *src);
 242 MODBUS_API float modbus_get_float_dcba(const uint16_t *src);
 243 MODBUS_API void modbus_set_float(float f, uint16_t *dest);
 244 MODBUS_API void modbus_set_float_dcba(float f, uint16_t *dest);
 245
 246 #include "modbus-tcp.h"
 247 #include "modbus-rtu.h"
 248
 249 MODBUS_END_DECLS
 250
 251 #endif  /* _MODBUS_H_ */