User manual

About the Example Applications ILX34-AENWG ♦ Point I/O Platform
User Manual Wireless POINT I/O Adapter

Page54of209 ProSoftTechnology,Inc.
 September19,2011

3.1 Support of Rack-optimized and Direct Connections
TheILX34‐AENWGadaptersupportsbothdirectandrack‐optimizedconnections.Adirect
connectionisareal‐timedatatransferlinkbetweenthecontrollerandwhatevermodule
occupiestheslotthattheconfigurationdatareferences.
 DirectconnectionmessagingoccursatacyclicratespecifiedbytheRPIduringconfiguration.

Arack‐optimizedconnectionisagroupingofdatafrommorethanoneI/Omoduleintoa
singleblockofdatasentoverasingleconnectionatthesamedatarate.
Rack‐optimizedconnectionsreducethetotalnumberofconnectionsneededtotransferdata
whenusingmanyI/Omodulesin
asystem.Thefollowingexampleillustratesthebenefitofrack‐
optimizedconnections.
Forexample,asystemcontains8digitalI/OmodulesinterfacedtoaILX34‐AENWGadapter.If
youusedirectconnectionstotransferdatatoeachoftheseI/Omodules,youneed8
connectionstotransferallofthedata,
onetoeachofthe8I/Omodules.Ifyouusearack‐
optimizedconnectiontotransferthedata,youonlyneedasingleconnection‐theconnectionto
theILX34‐AENWGadapter.
Important: Although rack-optimized connections offer an efficient way to use resources, there are
a few limitations on their use:
 You can use only rack-optimized connections to send data to and from digital I/O modules.
Analog or specialty I/O requires direct connections.
 All data is sent at the same time as the RPI rate of the ILX34-AENWG adapter.
Refer to the Rockwell Automation publication EtherNet/IP Performance and Application Guide,
publication number ENET-AP001, for more information on connections.

3.1.1 Mix Rack-optimized and Direct Connections
YoucanmixcommunicationformatsfordifferentI/Omodulescommunicatingthroughthesame
adapter.I/OmodulessetuptouserackoptimizationcommunicateattherateoftheRPI
configuredfortheILX34‐AENWGadapter.I/Omodulesconfiguredfordirectcommunication
communicateattheirownsetRPIsandignoretheILX34
‐AENWGadapter'sRPI.
