Pilz PNOZmulti 2

Modbus/TCP
OperatingManualCommunicationinterfaces
1002971EN03
51
6 Modbus/TCP
6.1 Systemrequirements
} PNOZmultiConfigurator:fromVersion9.0.0
} PNOZmB0+PNOZmESETH
PleasecontactPilzifyouhaveanolderversion.
6.2 Modbus/TCPBasics
Modbus/TCPisanopenfieldbusstandardpublishedbytheUserGroupMODBUSIDA(see
www.ModbusIDA.org).
Application Layer
Protocol
Modbus/TCP
TCP
(RFC 793)
IP
(RFC 791)
Industrial Ethernet
Physical Layer
Ethernet
Modbus/TCPisaprotocolbasedonIndustrialEthernet(TCP/IPoverEthernet).Itisoneof
theprotocolswithClient/Servercommunication.Dataistransferredviaarequest/response
mechanismusingfunctioncodes(FC).
Modbus/TCPisconnectionoriented,i.e.beforeusabledataistransferredviaModbus/TCP,
aconnectionmustfirstbeestablishedbetweentwoModbus/TCPinterfaces.Theinitiatorof
theconnectioniscalledtheClient.ThecommunicationspartnerwithwhichtheClientes
tablishestheconnectioniscalledtheServer.Whetheraconnectiononadeviceassumes
theroleofClientorServerisdefinedwhenaconnectionisconfigured.Asaresult,the
Server/Clientroleonlyappliesforthatspecificconnection.