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61
February 2010
Routing Servers Configuration
Master Port
When a master/slave protocol is to be used by remote devices,
specify the TCP Port number on the WI-MOD-E that the master
device will connect to. Set this field to 0 if there is no master device.
Slave Port
Specify the TCP port number on the WI-MOD-E that non-master
remote devices will connect to.
Max Connections
Enter the maximum number of devices that are allowed to connect to
this Routing Server (default is 32, maximum is 50).
ModBus Mode
If the remote devices are communicating using the ModBus RTU
protocol, select this option to enable the WI-MOD-E to route
ModBus data frames to the correct location.
Max Poll Fail
When ModBus Mode is enabled, enter the maximum number of
times a slave device may fail to respond to a master request before
that slave address is removed from the internal ModBus routing
tables (and it’s location must therefore be rediscovered using
broadcast messages). Enter 0 if entries in the routing table are never
to be cleared.
Inactivity Timeout
Enter the time, in seconds, after which if no data has been sent or
received on any remote device connection to this routing server then
that connection will be closed. Enter 0 if an inactivity timeout is not
required.
Send Keep-alive
TCP/IP messages can be used to maintain the status of inactive
remote device connections as an alternative to an inactivity time. If
this option is enabled then TCP keep-alive probes will be sent on
idle connections after the configurable Keepidle and Keepintvl times
(see the TCP/IP Configuration Fields table above).
Password
For added security, remote devices can be required to provide a
password in order to connect to the modem. Enter the password here
or leave blank if no password is required.
Each of the 3 Routing Server modes of operation is illustrated in the example configuration below
where it can be seen that 3 separate Routing Servers have been configured (note that in the majority
of actual applications that only 1 Routing Server would normally be configured per WI-MOD-E).
The first entry uses the ModBus aware protocol mode, the second entry uses the generic
Master/Slave mode, and the final entry uses Broadcast mode. We will take a closer look at the
configuration of each entry below.
Looking at the first entry a Routing Server has been configured to operate in the ModBus aware
protocol mode. The Master Port is set to 5001, so the remote TCP/IP client device where the
ModBus Master is located must connect to TCP Port 5001 of the WI-MOD-E. The Slave Port set to
5002, so that all remote TCP/IP client devices where ModBus Slaves are located must connect to
TCP Port 5002 of the WI-MOD-E.
