Data Sheet

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10
ETHERIO24TCPDATASHEET
AutoScan
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TheAutoScanmodewillallowthemoduletooriginatecommunicationwitha
remotedeviceoranotherEtherIO24module.Thismodeisveryusefulas
itallowsyoursoftwarethefreedomnottohavetopollthemoduleto
checkthestateoftheinputs
Protocol
EnablesAutoScanandsetstheProtocoltoeitherUDPorTCP.
ScanRateandFiltering
TheScanRateisa16‐bitvaluewhichisusedtodividethescanrateof
theAutoScanmodefromitsbaserateof50scansperseconddowntoauser
programmedratefrom25scanspersecondtoonescanper54minutes.When
setat1thescanrateis50scanspersecond,itis25scanspersecond
whenthevalueis2andsoon.
Thefiltervalueisusedtocountthenumberofidenticalreadsthatare
requiredbeforeaportvalueisconsideredvalidandsenttothetarget
device.Whensetat0thefilteristurnedoff,whensetat1theport
mustreadthesamefortwoscanstobeconsideredvalidandsenttothe
target.Highernumberssimplyincreasethenumberofidenticalreads
requiredbeforethevalueisconsideredvalid.
Careshouldbetakenwhenusinghighfiltervalueswithslowscanrates,
asthereportingtimeforachangeundertheseconditionscanbeover4
hours.
TargetIPAddressandPortNumber
ATargetIPAddressandPortNumberareprovidedtotelltheEtherIO24
modulewhatdestinationaddresstheAutoScandatahastobesenttoo.
©
2013ElexolPtyLtd Revision1.3
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