Applies To:
  • CitectSCADA 1.00, 1.01, 1.10, 1.11, 2.00, 2.01

Question: I have a 3 node Citect system, 1 I/O Server and 2 Display nodes. The I/O Server is using a Digiboard to communicate with the PLCs. When I startup the Display nodes, they also try to initialise the Digiboard, but as the Display nodes don't have Digiboards installed, I always get an error message. The Display nodes have the [IOSERVER] Server=0 parameter set in the Citect.INI file. 

Change the name of the IOServer on the Display nodes to another name eg [IOServer] Name=BadServer. This will stop Citect from trying to initialise the Digiboards (or other Com ports). Don't set the Name to blank, as Citect will use the default name 'IOServer' - which may be the same name as your I/O Server.

What is happening is that even though the IOServer is disabled, Citect is initialising the Communication Ports for the IOServer name (under the IOServer section). Citect does this so you can use the Communication Ports with the Cicode Com functions on a Display node that is not an I/O Server. If you change the name of the I/IOServer on the Display node to one which does not match the real I/O Server, Citect will not find any com ports associated with this computer when the Display node is started.