User manual

IEC61131 User and Reference Manual
April 22, 2008
121
The Addressing menu selects standard or extended Modbus addressing. Standard
addressing allows 255 stations and is compatible with standard Modbus devices. Extended
addressing allows 65534 stations, with stations 1 to 254 compatible with standard Modbus
devices. The default value is standard.
The Station menu sets the station number of the controller. The valid range is 1 to 255 if
standard addressing is used, and 1 to 65534 if extended addressing is used. The default
value is 1.
The Store and Forward selection controls forwarding of messages using IP based
protocols. If this option is enabled, messages will be forwarded according to the settings in
the store and forward routing table. The default value is disabled.
The Enron Modbus box selects whether Enron Modbus is enabled for the port. If this option
is enabled, the controller, in addition to regular Modbus messages, will handle Enron
Modbus messages.
The Enron Station box selects the Enron Modbus station address. The valid range for
Enron Station is 1 to 255 if the Addressing control is set to Standard. The valid range for
Enron Station is 1 to 65534 if the Addressing control is set to Extended. The Enron station
must be different from the Modbus station set in the Station edit box. This ensures Enron
Modbus and Modbus communication can occur on the same port.
Modbus/TCP
The Modbus/TCP property page is selected for editing by clicking Modbus/TCP in the tree
control section of the IP Configuration dialog. When selected the Modbus/TCP property page
is active.