Specifications

Chapter 8: NCR 7401 7890/7892 Scanner Differences 8-3
AftertheActiveTimeperiodexpires,iftheNCROPOSscannerdriver
doesnotgetanothermotionevent,themotorandlaserareturnedoff.
IfamotioneventisreceivedduringtheActiveTimeperiod,themotor
andlaserwillcontinuetorunandthetimerisrestarted.The
applicationusingNCROPOSshouldkeeptrackofthemotion
detectionevents(andthetimesincethelastevent)toensurethatthe
scannerisrunningwhentheapplicationisrequestingscannerinput.If
nomotioneventsarereceivedbeforetheActiveTimeperiodexpires,
andatransactionisstillactive,
theapplicationmusteitherrestartthe
scannerorperformsomeotherrecoveryprocedure,suchasaskingthe
customeriftheystillwantthesameserviceperformed.These
proceduresshouldbewelldesignedandtestedsothatthecustomeris
notattemptingtoscananitemwhenthemotorandlaser
areoff.
ThemotioneventsaredocumentedintheNCROPOSOnlineHelpfile
thatcomeswiththeNCROPOSsoftware.Thehelpfileisalsoavailable
ontheIPPwebsite(searchforaTitlecontainingOPOS).Useofthe
motiondetectorwithoutusingtheNCROPOSdriversisnot

recommendedandiscurrentlynotdocumented.
IftheapplicationisnotusingNCROPOS,itmustpreparethescanner
toreadusingtheEnableScannercommandandtheStartScanner
commandsequences.Thesecommandsarethesameasthe7890and
7892commandsasdocumentedintheNCRScanner/ScaleInterface
Programmer’sGuide.
OncetheStartCommandissuccessfullyissued,themotorandlaserare
turnedonfortheActiveTimeperiod. Theapplicationshouldkeep
trackofthetimesothatattheendoftheActiveTimeperiod,theStart
commandisre‐issuedorsomeotherprocedureis
performedto
continuethetransaction.AsnotedintheOPOSparagraphabove,the
designoftheseproceduresshouldbecarefullyconsideredtolimit
customerfrustration.