/* * Copyright © Stéphane Raimbault * * SPDX-License-Identifier: LGPL-2.1-or-later */ #ifndef MODBUS_TCP_H #define MODBUS_TCP_H #include "modbus.h" MODBUS_BEGIN_DECLS #define MODBUS_TCP_DEFAULT_PORT 502 #define MODBUS_TCP_SLAVE 0xFF /* 参考 Modbus_Application_Protocol_V1_1b.pdf 第四章第一节第5页 * TCP MODBUS 应用数据单元(ADU)= 253 字节数据 + MBAP 报文头(7 字节)= 共 260 字节 */ #define MODBUS_TCP_MAX_ADU_LENGTH 260 MODBUS_API modbus_t *modbus_new_tcp(const char *ip_address, int port); MODBUS_API int modbus_tcp_listen(modbus_t *ctx, int nb_connection); MODBUS_API int modbus_tcp_accept(modbus_t *ctx, int *s); MODBUS_API modbus_t *modbus_new_tcp_pi(const char *node, const char *service); MODBUS_API int modbus_tcp_pi_listen(modbus_t *ctx, int nb_connection); MODBUS_API int modbus_tcp_pi_accept(modbus_t *ctx, int *s); MODBUS_END_DECLS #endif /* MODBUS_TCP_H */