CJ2 CPU Unit Software User's Manual - CIP ETI

4 CPU Unit InitializationTables Comprising Routing TablesRouting tables consist of the following two tables. Local Network TableNetwork addresses from 1 to 127 are set for the Network Communications Units (CPU Bus Units)connected in the local PLC. The local network table is used by the CPU Unit to identify NetworkCommunications Units mounted to the local PLC and the corresponding communications networks ifmore than one Network Communications Unit is mounted to the PLC.This table shows which Network Communications Unitconnected in the local PLC must be passed through toreach a specified network.Unit number: AUnit number: BUnit number: CLocal PLCNetwork cLocal Network TableNetwork addressabcUnit numberABCNetwork bThe local network table gives the unit number of the Network Communications Unit connected in thelocal PLC and the corresponding address of the FINS network connected to that Unit for FINS communications. Relay Network TableNetwork aA relay network table is set to perform FINS communications across network layers. The relay networktable tells how to relay communications until the message reaches the final destination. The table givesthe network address and node address of the first relay point (i.e. first point to reach) on the route to adestination network (final network) to which the local PLC is not connected.The destination network is reached by progressing through the relay points.Relay Network TableDestination networkaddress(final destination)NetworkaddressRelayNodeaddressa b nRelay Network TableDestination networkaddress(final destination)NetworkaddressRelayNodeaddressb a mMessage addressed to network“a” is received.Node nNode mMessage addressed tonetwork “b” is received.Network bNetwork a4-12 CJ2 CPU Unit Software User’s Manual