IoT wireless communication data transmission module: multi-host gateway working mode, understand it in one article

成都亿佰特

IoT wireless communication data transmission module: multi-host gateway working mode, understand it in one article [Copy link]

The multi-host gateway can only work in TCP server mode and can process multiple Modbus TCP host requests at the same time. When a host request is not completed, the serial port server receives other host requests. At this time, the serial port server will arbitrate output on the RS485 bus (in layman's terms, it blocks subsequent instructions).

Simulation software demonstration (for comparison with the storage gateway, another debugging tool, MThings' Modbus debugging tool, is used):

Use Modbus Slave to simulate the slave and emulate 10 holding registers;

Add 4 network hosts;

Configure serial server parameters, serial server IP and port;

Select the simulated host, a total of 4 channels are simulated;

Use custom sending, 030000000A software automatically configures Modbus address, sends periodically in 200ms, and uses the same sending rules for four channels;

When the slave responds correctly and the host request rate is not high, the efficiency and real-time performance of this mode are good. If the slave response times out, it will also affect the host requests that have not been sent in the host cache. Since the Ethernet transmission rate is much higher than the serial port transmission rate, if the host requests frequently and the slave response delay is large, it will cause the gateway cache to overflow, resulting in a host response timeout.