modbus-tcp-private.h
1.02 KB
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#pragma once
#define _MODBUS_TCP_HEADER_LENGTH 7
#define _MODBUS_TCP_PRESET_REQ_LENGTH 12
#define _MODBUS_TCP_PRESET_RSP_LENGTH 8
#define _MODBUS_TCP_CHECKSUM_LENGTH 0
/* In both structures, the transaction ID must be placed on first position
to have a quick access not dependant of the TCP backend */
typedef struct _modbus_tcp
{
/* Extract from MODBUS Messaging on TCP/IP Implementation Guide V1.0b
(page 23/46):
The transaction identifier is used to associate the future response
with the request. This identifier is unique on each TCP connection. */
uint16_t t_id;
/* TCP port */
int port;
/* IP address */
char ip[16];
} modbus_tcp_t;
#define _MODBUS_TCP_PI_NODE_LENGTH 1025
#define _MODBUS_TCP_PI_SERVICE_LENGTH 32
typedef struct _modbus_tcp_pi
{
/* Transaction ID */
uint16_t t_id;
/* TCP port */
int port;
/* Node */
char node[_MODBUS_TCP_PI_NODE_LENGTH];
/* Service */
char service[_MODBUS_TCP_PI_SERVICE_LENGTH];
} modbus_tcp_pi_t;