Honeywell XYR 400E User Manual page 58

192.168.0.200 is the IP address of unit C – which is the Modbus TCP Server we are reading from.
Response Timeout 1000 ms specifies that unit C must respond to this message within 1000ms.
Comm Fail Register 0 specifies the local register where the communications status for this mapping
will be stored.
The second mapping reads 8 registers from serial unit D into onboard registers in unit B. Note that
in this case the specified Device ID 6 is the Modbus Address of the serial device D, while the Server
IP Address 192.168.0.200 is the IP Address of unit C since the Modbus TCP to RTU Gateway at
unit C converts the Modbus TCP message to Modbus RTU and routes it out the serial port to unit D.
The third mapping takes the 8 registers read by the second mapping and writes them to the serial
unit A. The specified Device ID 5 is the Modbus Address of the serial device A, and the Server IP
Address 192.168.0.196 is the IP Address of the local unit B since the local Modbus TCP to RTU
Gateway is to route the message out the serial port to unit A.
Since the XYR 400E supports Modbus TCP Client and Server simultaneously, the Modbus TCP
Server for unit B above could also be enabled. This would allow one (or more) external Modbus
TCP Clients anywhere on the extended wired or wireless network to connect to unit B and monitor
the status of the I/O registers – including the I/O at units A, C, and D. This is a very powerful and
flexible feature which could, for example, be exploited by a central monitoring facility or SCADA.
Version 1 XYR400E Ethernet Modem 58
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