Data Sheet

TeledyneLeCroyCorporation RecordingRules‐USB2.0
290 USBProtocolSuiteUserManual
Setting a Counter
Tosetacounter:
1. OpentheRecordingRulespage,selectanevent,anddragittotheGlobalStateor
Sequencecell.
2. Countscanonlybesetonaperchannelbasis,sopresstheUporDownchannel
buttonstoselectthechannelonwhichthecountisperformed.
3. Right‐clicktheselectedeventandselectAddCounterfromthemenutoopenthe
Propertiesdialog.
4. InthetextboxtotherightofthelabelCount,enteravalue.Makesurethecheckbox
totheleftofthewordCountischecked.
5. ClicktheXinthetoprightcornerofthedialogboxtoclosethedialog.Acounter
buttonshouldappearjustbelowyourselectedevent.
Changing a Counter Value
Tochangethecountervalue:
1. Clickthesmallbluedotintheupper‐leftcornerofthecounterbutton.Amenu
appears.
2. SelectChangeCounterValue.
3. Enteranewvalueinthepop‐updialogbox.Thiscausesthenewvaluetoappearin
thecounterbutton.
5.8.11 Performance Considerations
TherearevariousUSB2.0scenarioswhichcanhaveaheavyimpactonperformanceboth
ofuploadinganddecoding/viewingofatrace.
Itisrecommendedthat(ifyoucan)youfilteroutdatathatisnotnecessaryfordebugging
yourscenario.Herearecoupleofexamples:
 1.Filterouttrafficfromdevicesyouarenotdebugging.Somedevicestrafficwill
fillthebufferwiththeirdatapreventingyoufromgettingthedatafromthe
deviceyouwant.Topreventthis,youcanfilteroutallthetrafficfroman
addressusingtheTransactionFilterandsettingtheaddresstotheoneyoudon't
want.
 2.Somedevices"NAKForever"(orwhatseemslikeforever).Thesefillthebuffer
withminimallyusableinformation(unlessitistheNAK'syouareinterestedin).
HavingmillionsofNAKtransactionswilladverselyeffectdecodingandscrolling
throughyourtracefile.ThiscanbepreventedbyfilteringoutNAKtransactions
usingthetransactionfilter.