/* Copyright (C) 2001-2008 Stéphane Raimbault This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This library 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 General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #ifndef _MODBUS_H_ #define _MODBUS_H_ #include #include #include #define MODBUS_TCP_DEFAULT_PORT 502 #define HEADER_LENGTH_RTU 0 #define PRESET_QUERY_SIZE_RTU 6 #define PRESET_RESPONSE_SIZE_RTU 2 #define HEADER_LENGTH_TCP 6 #define PRESET_QUERY_SIZE_TCP 12 #define PRESET_RESPONSE_SIZE_TCP 8 #define CHECKSUM_SIZE_RTU 2 #define CHECKSUM_SIZE_TCP 0 /* 8 + HEADER_LENGTH_TCP */ #define MIN_QUERY_SIZE 14 /* MIN_RESPONSE_LENGTH + MAX(MAX*) */ #define MAX_PACKET_SIZE 261 #define MAX_READ_STATUS 800 #define MAX_READ_HOLD_REGS 100 #define MAX_READ_INPUT_REGS 100 #define MAX_WRITE_COILS 800 #define MAX_WRITE_REGS 100 #define REPORT_SLAVE_ID_SIZE 75 /* Time out between trames in microsecond */ #define TIME_OUT_BEGIN_OF_TRAME 500000 #define TIME_OUT_END_OF_TRAME 500000 #ifndef FALSE #define FALSE 0 #endif #ifndef TRUE #define TRUE 1 #endif #ifndef OFF #define OFF 0 #endif #ifndef ON #define ON 1 #endif /* Function codes */ #define FC_READ_COIL_STATUS 0x01 /* discretes inputs */ #define FC_READ_INPUT_STATUS 0x02 /* discretes outputs */ #define FC_READ_HOLDING_REGISTERS 0x03 #define FC_READ_INPUT_REGISTERS 0x04 #define FC_FORCE_SINGLE_COIL 0x05 #define FC_PRESET_SINGLE_REGISTER 0x06 #define FC_READ_EXCEPTION_STATUS 0x07 #define FC_FORCE_MULTIPLE_COILS 0x0F #define FC_PRESET_MULTIPLE_REGISTERS 0x10 #define FC_REPORT_SLAVE_ID 0x11 /* Protocol exceptions */ #define ILLEGAL_FUNCTION -0x01 #define ILLEGAL_DATA_ADDRESS -0x02 #define ILLEGAL_DATA_VALUE -0x03 #define SLAVE_DEVICE_FAILURE -0x04 #define SERVER_FAILURE -0x04 #define ACKNOWLEDGE -0x05 #define SLAVE_DEVICE_BUSY -0x06 #define SERVER_BUSY -0x06 #define NEGATIVE_ACKNOWLEDGE -0x07 #define MEMORY_PARITY_ERROR -0x08 #define GATEWAY_PROBLEM_PATH -0x0A #define GATEWAY_PROBLEM_TARGET -0x0B /* Local */ #define COMM_TIME_OUT -0x0C #define PORT_SOCKET_FAILURE -0x0D #define SELECT_FAILURE -0x0E #define TOO_MANY_DATAS -0x0F #define INVALID_CRC -0x10 #define INVALID_EXCEPTION_CODE -0x11 #define CONNECTION_CLOSED -0x12 /* Internal using */ #define MSG_SIZE_UNDEFINED -1 typedef enum { RTU, TCP } type_com_t; typedef enum { RECONNECT_ON_ERROR, NOP_ON_ERROR } error_handling_t; /* This structure is byte-aligned */ typedef struct { /* Communication : RTU or TCP */ type_com_t type_com; /* 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[67]; #else char device[19]; #endif /* Parity: "even", "odd", "none" */ char parity[5]; /* Bauds: 19200 */ int baud_i; /* Data bit */ int data_bit; /* Stop bit */ int stop_bit; /* Save old termios settings */ struct termios old_tios; /* Descriptor (tty or socket) */ int fd; /* Flag debug */ int debug; /* IP address */ char ip[16]; /* TCP port */ uint16_t port; /* Header length used for offset */ int header_length; /* Checksum size RTU = 2 and TCP = 0 */ int checksum_size; /* In error_treat with TCP, do a reconnect or just dump the error */ error_handling_t error_handling; } modbus_param_t; typedef struct { int nb_coil_status; int nb_input_status; int nb_input_registers; int nb_holding_registers; uint8_t *tab_coil_status; uint8_t *tab_input_status; uint16_t *tab_input_registers; uint16_t *tab_holding_registers; } modbus_mapping_t; /* All functions used for sending or receiving data return : - the numbers of values (bits or word) if success (0 or more) - less than 0 for exceptions errors */ /* Reads the boolean status of coils and sets the array elements in the destination to TRUE or FALSE */ int read_coil_status(modbus_param_t *mb_param, int slave, int start_addr, int count, uint8_t *dest); /* Same as read_coil_status but reads the slaves input table */ int read_input_status(modbus_param_t *mb_param, int slave, int start_addr, int count, uint8_t *dest); /* Reads the holding registers in a slave and put the data into an array */ int read_holding_registers(modbus_param_t *mb_param, int slave, int start_addr, int count, uint16_t *dest); /* Reads the input registers in a slave and put the data into an array */ int read_input_registers(modbus_param_t *mb_param, int slave, int start_addr, int count, uint16_t *dest); /* Turns on or off a single coil on the slave device */ int force_single_coil(modbus_param_t *mb_param, int slave, int coil_addr, int state); /* Sets a value in one holding register in the slave device */ int preset_single_register(modbus_param_t *mb_param, int slave, int reg_addr, int value); /* Takes an array of ints and sets or resets the coils on a slave appropriatly */ int force_multiple_coils(modbus_param_t *mb_param, int slave, int start_addr, int coil_count, uint8_t *data); /* Copy the values in an array to an array on the slave */ int preset_multiple_registers(modbus_param_t *mb_param, int slave, int start_addr, int reg_count, uint16_t *data); /* Returns some useful information about the modbus controller */ int report_slave_id(modbus_param_t *mb_param, int slave, uint8_t *dest); /* Initialises a parameters structure - device : "/dev/ttyS0" - baud : 19200 - parity : "even", "odd" or "none" - data_bits : 5, 6, 7, 8 - stop_bits : 1, 2 */ void modbus_init_rtu(modbus_param_t *mb_param, char *device, int baud, char *parity, int data_bit, int stop_bit); /* Initialises a parameters structure for TCP - ip : "192.168.0.5" - port : 1099 Set the port to MODBUS_TCP_DEFAULT_PORT to use the default one (502). It's convenient to use a port number greater than or equal to 1024 because it's not necessary to be root to use this port number. */ void modbus_init_tcp(modbus_param_t *mb_param, char *ip_address, uint16_t port); /* By default, the error handling mode used is RECONNECT_ON_ERROR. With RECONNECT_ON_ERROR, the library will attempt an immediate reconnection which may hang for several seconds if the network to the remote target unit is down. With NOP_ON_ERROR, it is expected that the application will check for network error returns and deal with them as necessary. This function is only useful in TCP mode. */ void modbus_set_error_handling(modbus_param_t *mb_param, error_handling_t error_handling); /* Sets up a serial port for RTU communications to modbus or a TCP connexion */ int modbus_connect(modbus_param_t *mb_param); /* Closes the serial port and restores the previous port configuration or close the TCP connexion */ void modbus_close(modbus_param_t *mb_param); /* Sets debug mode */ void modbus_set_debug(modbus_param_t *mb_param, int boolean); /* Slave/client functions */ int modbus_mapping_new(modbus_mapping_t *mb_mapping, int nb_coil_status, int nb_input_status, int nb_holding_registers, int nb_input_registers); void modbus_mapping_free(modbus_mapping_t *mb_mapping); int modbus_init_listen_tcp(modbus_param_t *mb_param); int modbus_listen(modbus_param_t *mb_param, uint8_t *query, int *query_size); void manage_query(modbus_param_t *mb_param, uint8_t *query, int query_size, modbus_mapping_t *mb_mapping); /* Not implemented : - read_exception_status() */ /** Utils **/ /* Set many inputs/coils form a single byte value (all 8 bits of the byte value are setted) */ void set_bits_from_byte(uint8_t *dest, uint16_t address, const uint8_t value); /* Set many inputs/coils from a table of bytes (only the bits between address and address + nb_bits are setted) */ void set_bits_from_bytes(uint8_t *dest, uint16_t address, uint16_t nb_bits, const uint8_t *tab_byte); /* Get the byte value from many inputs/coils. To obtain a full byte, set nb_bits to 8. */ uint8_t get_byte_from_bits(const uint8_t *src, uint16_t address, int nb_bits); #endif /* _MODBUS_H_ */