Chengdu Ebyte Electronic Technology Co., Ltd.
NB144 User Manual
Copyright ©2012
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Chengdu Ebyte Electronic Technology Co., Ltd.
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5.4.2 multi-host mode
Relatively simple protocol conversion can only have one Modbus master station, while the multi-host mode
can simultaneously access multiple Modbus TCP hosts. When multiple Modbus hosts access at the same time, the
Modbus gateway will perform bus occupancy scheduling (RS -485 The bus can only process one request at a time,
and the multi-host mode will sort and process according to the TCP request, and other links will wait), thus solving
the bus conflict problem (currently, it supports up to 9 Modbus channels in single server mode TCP host connection,
multi-channel host access at the same time should pay attention to the matching of the request interval and timeout
time, otherwise the transmission rate of the serial port is much lower than the transmission rate of the Ethernet,
resulting in packet loss. If you need a fast response, it is recommended to use a "storage gateway" ), it only
supports working in TCP server mode, and the slave can only be on the serial port, otherwise it cannot work
normally.
As the number of hosts increases, the Modbus timeout should be increased accordingly. If multiple hosts need
continuous high-speed requests, it is recommended to use "storage gateway", and it is recommended to configure
"simple protocol conversion" when there are no multiple hosts.
