Data Sheet

USBProtocolSuiteUserManual 529
Chapter 11
Traffic Generation 2.0
USB2.0TrafficGenerationallowsyoutogenerateUSB2.0trafficandtestdesignsunder
realisticconditions.Traffic Generationcanalsotransmitknownbadpackets,providingan
opportunityforengineerstoobservehowadevicehandlesspecificadverseconditions.
The2.0Generationscriptscancreatealmostarbitrarystreamsofpackets,butthe
responsibilityforcreatingasequencewhichperformsinanexpectedwayislefttothe
user.Forexample,ifaHostEmulationscriptstartswithjustsendingbulkdataonan
endpoint,norealdevicepurchasedinthestorecanreacttoit,asitexpectstobe
enumeratedandbeinthecorrectstatewhentheBulktransferbegins.IntheDevice
Emulationsituation,itisexpectedthatthedevicewillsupplyallthecorrectenumeration
responses,intheorderexpectedbythehost,forittoproceedtoit'snormalbehavior
mode.Sincedifferenthostsmayenumeratedevicesinslightlydifferentorders,youmay
havetoadjustthedeviceemulationscriptfiletomatchthis.BycreatingtheHost
EmulationorDeviceEmulationscriptfromtheprocessofexportingfromarealtracewith
arealDeviceorHost,thelikelihoodofstartingoutwithaworkingscriptisincreased
enormously,sincethebehaviorshouldberepeatable.
Note:FortrafficgenerationforUSB3.1,see“TrafficGeneration3.1Exerciser”onpage 569.
11.1 Connecting to Voyager M3/M3i
TheconnectionsdifferforHostEmulationandDeviceEmulation.
FullSpeed,LowSpeed,andHiSpeedconnectionsarethesame.
Hi/Full/Low Speed Host Emulation
ForHostEmulationHi,Full,orLowSpeed,connecttotheVoyagerM3/M3iaccordingto
thefollowingdiagram(seeFigure 11.1onpage 530.).