Schneider Electric 174 CEV manual A, B C, D

Configuring the Bridge
37
Figure17showsan example of the mapping ofamessage between two
ModbusPlusnodesthrough a pairofEthernetbridges.
Figure17 Example:Linking ModbusPlusNetworks Through EthernetBridges
BridgeBridge
Modbus
Plus
Ethernet
Originating
NodeDestination
Node
Node25
Node12Routiing:25.8.17.33.0
IP:205.167.8.10
Modbus
Plus
TCP
MapEntry:
TCP_17:205.167.8.10 MBP_33:12.0.0.0.0
ModbusPlus
MapEntry:
A
B C
D
1 2
A.TheMessageisOriginated
AModbusPlusnode originatesamessage withthe five--byteModbusPluspath
25.8.17.33.0.The message isaddressed tothe bridge atnode address 25,
specified inthe firstrouting byte.
Bridge 1 (node 25) receivesthe message and opensitsinternalpath 8.Thispath
is specified inthe second routing byte.
B.Bridge1MapstheMessageto TCP/IP
Bridge 1 indexesintoitsTCPMapping table atlocation TCP_17,specified bythe
thirdrouting byte.Location 17 containsthe IPaddress 205.167.8.10.The bridge
forwardsthe message tothisIPaddress,asecond bridge.
C.Bridge2MapstheMessagetoModbusPlus
Bridge 2 receivesthe message and indexesintoitsModbusPlusMapping tableat
location MBP_33,specified bythe fourth byte ofrouting inthe originalmessage.
Location 33 containsthe ModbusPlusrouting path12.0.0.0.0to a node on the
ModbusPlusnetworkatBridge 2.
D.TheMessageisDelivered
The message isdelivered tothe destinationnode 12on theModbusPlusnetwork.
The node actsupon the Modbus command embedded inthe message.