/*

* Copyright © 2001-2013 Stéphane Raimbault <stephane.raimbault@gmail.com>

*

* SPDX-License-Identifier: LGPL-2.1+

*/

#ifndef MODBUS_H

#define MODBUS_H

/* Add this for macros that defined unix flavor */

#if (defined(__unix__) || defined(unix)) && !defined(USG)

#include <sys/param.h>

#endif

#ifndef _MSC_VER

#include <stdint.h>

#else

#include "stdint.h"

#endif

#include "modbus-version.h"

#if defined(_MSC_VER)

# if defined(DLLBUILD)

/* define DLLBUILD when building the DLL */

# define MODBUS_API __declspec(dllexport)

# else

# define MODBUS_API __declspec(dllimport)

# endif

#else

# define MODBUS_API

#endif

#ifdef __cplusplus

# define MODBUS_BEGIN_DECLS extern "C" {

# define MODBUS_END_DECLS }

#else

# define MODBUS_BEGIN_DECLS

# define MODBUS_END_DECLS

#endif

MODBUS_BEGIN_DECLS

#ifndef FALSE

#define FALSE 0

#endif

#ifndef TRUE

#define TRUE 1

#endif

#ifndef OFF

#define OFF 0

#endif

#ifndef ON

#define ON 1

#endif

/* Modbus function codes */

#define MODBUS_FC_READ_COILS 0x01

#define MODBUS_FC_READ_DISCRETE_INPUTS 0x02

#define MODBUS_FC_READ_HOLDING_REGISTERS 0x03

#define MODBUS_FC_READ_INPUT_REGISTERS 0x04

#define MODBUS_FC_WRITE_SINGLE_COIL 0x05

#define MODBUS_FC_WRITE_SINGLE_REGISTER 0x06

#define MODBUS_FC_READ_EXCEPTION_STATUS 0x07

#define MODBUS_FC_WRITE_MULTIPLE_COILS 0x0F

#define MODBUS_FC_WRITE_MULTIPLE_REGISTERS 0x10

#define MODBUS_FC_REPORT_SLAVE_ID 0x11

#define MODBUS_FC_MASK_WRITE_REGISTER 0x16

#define MODBUS_FC_WRITE_AND_READ_REGISTERS 0x17

#define MODBUS_BROADCAST_ADDRESS 0

/* Modbus_Application_Protocol_V1_1b.pdf (chapter 6 section 1 page 12)

* Quantity of Coils to read (2 bytes): 1 to 2000 (0x7D0)

* (chapter 6 section 11 page 29)

* Quantity of Coils to write (2 bytes): 1 to 1968 (0x7B0)

*/

#define MODBUS_MAX_READ_BITS 2000

#define MODBUS_MAX_WRITE_BITS 1968

/* Modbus_Application_Protocol_V1_1b.pdf (chapter 6 section 3 page 15)

* Quantity of Registers to read (2 bytes): 1 to 125 (0x7D)

* (chapter 6 section 12 page 31)

* Quantity of Registers to write (2 bytes) 1 to 123 (0x7B)

* (chapter 6 section 17 page 38)

* Quantity of Registers to write in R/W registers (2 bytes) 1 to 121 (0x79)

*/

#define MODBUS_MAX_READ_REGISTERS 125

#define MODBUS_MAX_WRITE_REGISTERS 123

#define MODBUS_MAX_WR_WRITE_REGISTERS 121

#define MODBUS_MAX_WR_READ_REGISTERS 125

/* The size of the MODBUS PDU is limited by the size constraint inherited from

* the first MODBUS implementation on Serial Line network (max. RS485 ADU = 256

* bytes). Therefore, MODBUS PDU for serial line communication = 256 - Server

* address (1 byte) - CRC (2 bytes) = 253 bytes.

*/

#define MODBUS_MAX_PDU_LENGTH 253

/* Consequently:

* - RTU MODBUS ADU = 253 bytes + Server address (1 byte) + CRC (2 bytes) = 256

* bytes.

* - TCP MODBUS ADU = 253 bytes + MBAP (7 bytes) = 260 bytes.

* so the maximum of both backend in 260 bytes. This size can used to allocate

* an array of bytes to store responses and it will be compatible with the two

* backends.

*/

#define MODBUS_MAX_ADU_LENGTH 260

/* Random number to avoid errno conflicts */

#define MODBUS_ENOBASE 112345678

/* Protocol exceptions */

enum {

MODBUS_EXCEPTION_ILLEGAL_FUNCTION = 0x01,

MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS,

MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE,

MODBUS_EXCEPTION_SLAVE_OR_SERVER_FAILURE,

MODBUS_EXCEPTION_ACKNOWLEDGE,

MODBUS_EXCEPTION_SLAVE_OR_SERVER_BUSY,

MODBUS_EXCEPTION_NEGATIVE_ACKNOWLEDGE,

MODBUS_EXCEPTION_MEMORY_PARITY,

MODBUS_EXCEPTION_NOT_DEFINED,

MODBUS_EXCEPTION_GATEWAY_PATH,

MODBUS_EXCEPTION_GATEWAY_TARGET,

MODBUS_EXCEPTION_MAX

};

#define EMBXILFUN (MODBUS_ENOBASE + MODBUS_EXCEPTION_ILLEGAL_FUNCTION)

#define EMBXILADD (MODBUS_ENOBASE + MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS)

#define EMBXILVAL (MODBUS_ENOBASE + MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE)

#define EMBXSFAIL (MODBUS_ENOBASE + MODBUS_EXCEPTION_SLAVE_OR_SERVER_FAILURE)

#define EMBXACK (MODBUS_ENOBASE + MODBUS_EXCEPTION_ACKNOWLEDGE)

#define EMBXSBUSY (MODBUS_ENOBASE + MODBUS_EXCEPTION_SLAVE_OR_SERVER_BUSY)

#define EMBXNACK (MODBUS_ENOBASE + MODBUS_EXCEPTION_NEGATIVE_ACKNOWLEDGE)

#define EMBXMEMPAR (MODBUS_ENOBASE + MODBUS_EXCEPTION_MEMORY_PARITY)

#define EMBXGPATH (MODBUS_ENOBASE + MODBUS_EXCEPTION_GATEWAY_PATH)

#define EMBXGTAR (MODBUS_ENOBASE + MODBUS_EXCEPTION_GATEWAY_TARGET)

/* Native libmodbus error codes */

#define EMBBADCRC (EMBXGTAR + 1)

#define EMBBADDATA (EMBXGTAR + 2)

#define EMBBADEXC (EMBXGTAR + 3)

#define EMBUNKEXC (EMBXGTAR + 4)

#define EMBMDATA (EMBXGTAR + 5)

#define EMBBADSLAVE (EMBXGTAR + 6)

extern const unsigned int libmodbus_version_major;

extern const unsigned int libmodbus_version_minor;

extern const unsigned int libmodbus_version_micro;

typedef struct _modbus modbus_t;

typedef struct {

int nb_bits;

int nb_input_bits;

int nb_input_registers;

int nb_registers;

uint8_t *tab_bits;

uint8_t *tab_input_bits;

uint16_t *tab_input_registers;

uint16_t *tab_registers;

} modbus_mapping_t;

typedef enum

{

MODBUS_ERROR_RECOVERY_NONE = 0,

MODBUS_ERROR_RECOVERY_LINK = (1<<1),

MODBUS_ERROR_RECOVERY_PROTOCOL = (1<<2)

} modbus_error_recovery_mode;

MODBUS_API int modbus_set_slave(modbus_t* ctx, int slave);

MODBUS_API int modbus_set_error_recovery(modbus_t *ctx, modbus_error_recovery_mode error_recovery);

MODBUS_API int modbus_set_socket(modbus_t *ctx, int s);

MODBUS_API int modbus_get_socket(modbus_t *ctx);

MODBUS_API int modbus_get_response_timeout(modbus_t *ctx, uint32_t *to_sec, uint32_t *to_usec);

MODBUS_API int modbus_set_response_timeout(modbus_t *ctx, uint32_t to_sec, uint32_t to_usec);

MODBUS_API int modbus_get_byte_timeout(modbus_t *ctx, uint32_t *to_sec, uint32_t *to_usec);

MODBUS_API int modbus_set_byte_timeout(modbus_t *ctx, uint32_t to_sec, uint32_t to_usec);

MODBUS_API int modbus_get_header_length(modbus_t *ctx);

MODBUS_API int modbus_connect(modbus_t *ctx);

MODBUS_API void modbus_close(modbus_t *ctx);

MODBUS_API void modbus_free(modbus_t *ctx);

MODBUS_API int modbus_flush(modbus_t *ctx);

MODBUS_API int modbus_set_debug(modbus_t *ctx, int flag);

MODBUS_API const char *modbus_strerror(int errnum);

MODBUS_API int modbus_read_bits(modbus_t *ctx, int addr, int nb, uint8_t *dest);

MODBUS_API int modbus_read_input_bits(modbus_t *ctx, int addr, int nb, uint8_t *dest);

MODBUS_API int modbus_read_registers(modbus_t *ctx, int addr, int nb, uint16_t *dest);

MODBUS_API int modbus_read_input_registers(modbus_t *ctx, int addr, int nb, uint16_t *dest);

MODBUS_API int modbus_write_bit(modbus_t *ctx, int coil_addr, int status);

MODBUS_API int modbus_write_register(modbus_t *ctx, int reg_addr, int value);

MODBUS_API int modbus_write_bits(modbus_t *ctx, int addr, int nb, const uint8_t *data);

MODBUS_API int modbus_write_registers(modbus_t *ctx, int addr, int nb, const uint16_t *data);

MODBUS_API int modbus_mask_write_register(modbus_t *ctx, int addr, uint16_t and_mask, uint16_t or_mask);

MODBUS_API int modbus_write_and_read_registers(modbus_t *ctx, int write_addr, int write_nb,

const uint16_t *src, int read_addr, int read_nb,

uint16_t *dest);

MODBUS_API int modbus_report_slave_id(modbus_t *ctx, int max_dest, uint8_t *dest);

MODBUS_API modbus_mapping_t* modbus_mapping_new(int nb_bits, int nb_input_bits,

int nb_registers, int nb_input_registers);

MODBUS_API void modbus_mapping_free(modbus_mapping_t *mb_mapping);

MODBUS_API int modbus_send_raw_request(modbus_t *ctx, uint8_t *raw_req, int raw_req_length);

MODBUS_API int modbus_receive(modbus_t *ctx, uint8_t *req);

MODBUS_API int modbus_receive_confirmation(modbus_t *ctx, uint8_t *rsp);

MODBUS_API int modbus_reply(modbus_t *ctx, const uint8_t *req,

int req_length, modbus_mapping_t *mb_mapping);

MODBUS_API int modbus_reply_exception(modbus_t *ctx, const uint8_t *req,

unsigned int exception_code);

/**

* UTILS FUNCTIONS

**/

#define MODBUS_GET_HIGH_BYTE(data) (((data) >> 8) & 0xFF)

#define MODBUS_GET_LOW_BYTE(data) ((data) & 0xFF)

#define MODBUS_GET_INT32_FROM_INT16(tab_int16, index) ((tab_int16[(index)] << 16) + tab_int16[(index) + 1])

#define MODBUS_GET_INT16_FROM_INT8(tab_int8, index) ((tab_int8[(index)] << 8) + tab_int8[(index) + 1])

#define MODBUS_SET_INT16_TO_INT8(tab_int8, index, value) \

do { \

tab_int8[(index)] = (value) >> 8; \

tab_int8[(index) + 1] = (value) & 0xFF; \

} while (0)

MODBUS_API void modbus_set_bits_from_byte(uint8_t *dest, int idx, const uint8_t value);

MODBUS_API void modbus_set_bits_from_bytes(uint8_t *dest, int idx, unsigned int nb_bits,

const uint8_t *tab_byte);

MODBUS_API uint8_t modbus_get_byte_from_bits(const uint8_t *src, int idx, unsigned int nb_bits);

MODBUS_API float modbus_get_float(const uint16_t *src);

MODBUS_API float modbus_get_float_dcba(const uint16_t *src);

MODBUS_API void modbus_set_float(float f, uint16_t *dest);

MODBUS_API void modbus_set_float_dcba(float f, uint16_t *dest);

#include "modbus-tcp.h"

#include "modbus-rtu.h"

MODBUS_END_DECLS

#endif /* MODBUS_H */