functional verification questions

7/27/2019 Functional Verification Questions

1/22

FUNCTIONAL VERIFICATION QUESTIONS

(Qi1)Explaino ehowi tooinjectqare crcierroroq jinre aipacketowhichqhas

justzdatau yande ocrczx fields.Ans:

Crcierroro einjecttioni canobeqdonere byimodifyingoq jthere crcivalueoonly.q

Ifidatao eisi modifiedotoqinjectre crcierror,oq jthenre itimayoendqup

inz auysituatione othatzx the new modified packet may have the same crc.

Foriexampleo e,i aopacketqofre lengthi5oq jbitsre withi3obitsqof dataz andu y2eobitszx of

crc value.

Thenithereo ewilli beo8qpacketsre ofidifferentoq jdata.re Thereiareoonlyq4

possiblez crcu yvalues.e o

So,iforo eonei crcovalue,qtherere couldibeoq jmorere thanioneodataqvalues

whichz areu ycorrect.www.testbench.in

Ifiyouo emodifyi theodata,qthenre theinewoq jdatare mayihaveotheqsame

crczvalue,u ywhiche owillzx not be resulted as crc error.

Forioneo edatai field,othereqwillre oneionlyoq jonere crcivalue,obyqchanging

thezcrcu yvalue,e ocrczx error will be injected for sure.

(Qi2)o eHowi dooyouqknowre wheniverificationoq jcompleted?

Ans:i

Verificationiiso eneveri completedoasqperre me.i

Iicano eonlyi sayothatqmyre verificationitaskoq jisre completediwhenoIqverified

allz theu ypointse omentionszx in test plan.

(Qi3)o eHowi toodetectqdeadlockre conditionsiinoq jFSMsre ?

.....w.....w......w......t.....e.....s.....t......b.....e.....n.....c.....h......i.....n

(Qi4)o eHowi tooavoidqracere conditionibetweenoq jTestbenchre andiDUTo?www.testbench.in

Ans:

Iniverilogo eori VHDL,o

i

1)Theiclocko ewhichi isogivenqtore DUTiandoq jTestbenchre shouldihaveoaqphase

difference.z

2)DUTishouldo eworki oroposedgeqofre clockiandoq jtestbenchre shouldiworkoonqnegedgeofz clock.
http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/


2/22

3)Testbenchioutputo eandi DUTooutputqpinsre shouldialwaysoq jbere driveniusingononqbloc

king statements.

IniSV,o e

1)Theiaboveo edefinei 3otechniques.

2)Clockingiblocks.www.testbench.in

3)Programiblock.

(Qi5)o eWhati isomutex?

Ans:

Aimutualo eexclusioni oroMUTEXqre essentialifunctionoq jisre toimakeoitqpossible

forz au ymultiplee oprocesseszx to make use of a single resource.

Wheniao esinglei resourceoisqrequiredre byimultipleoq jprocesses,re MUTEXiwillomakeqsure

thatz onlyu yonee oprocesszx will be granted the access at a time.

Foriexample,

AiDUTo ehasi aomemoryqtore storeitheoq jconfigurationre registers.iTooaccessqthe

memory,z letsu ysay,e oazx protocol is defined to read the memory of one location at a

time......w.....w......w......t.....e.....s.....t......b.....e.....n.....c.....h......i.....n

Testbenchimayo erequirei tooaccessqthere configuration/status/interruptiregistersoq jatre ti

mesifromodifferentqplaces. Forz example,u yae omonitorzx is reading register location of

status bit, while the testcase is reading a configuration register.Toiaccesso ethei memory,oTestcaseqandre monitoriwilloq jsendre theiaddressoofqthe

locationsz andu yreade ocommand.zx But the DUT can accept only one read request at a

time. www.testbench.in

Byiusingo eMUTEX,i accessotoqmemoryre interfaceicanoq jbere grantedionceoatqa

time,z sou ythee oreadzx operations by monitor and testcases will not collide.

IniSV,o etoi createoaqMUTEX,re constructiaoq jsemaphorere withioneokey.

Aikeyo eisi giveno qtore eitherimonitoroq jorre testcaseitooreadqoperation

basedzonu ywhoe ocomeszx first. Once the key is returned, other waiting component can take

the key and start its operation.

Someitimes,o ethei keyowhichqisre consumedimayoq jnotre beiretunedowhichqleads

toz deadu ylocke ocondition.zx So if a key is not returned, then a timeout should happen and a

error message should be triggered.

(Qi6)o eWhati isosemaphore?

Ans:

Conceptually,iao esemaphorei isoaqbucket.re Wheniaoq jsemaphorere isiallocated,oaqbucke
http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/


3/22

t thatz containsu yae ofixedzx number of keys is created. Processes using semaphores must

first procure a key from the bucket before they can continue to execute. If a specific process

requires a key, only a fixed number of occurrences of that process can be in progress

simultaneously. All others must wait until a sufficient number of keys is returned to the

bucket. Semaphores are typically used for mutual exclusion, access control to shared

resources, and basic synchronization.www.testbench.in

(Qi7)o eWhati isotheqneedre ofiregression?

Ans:

1)iChangeso eini theoRTLq(re development,ienhancementoq jorre bugifix)omayqcause

existingz functionalityu ytoe obreak.zx

2)iToo ecreatei newoscenariosqbyre givingidifferentoq jseedsre toirandomizationoengine.q

(Qi8)o eWhati isorandomization?

Ans:

Itiiso enoti possibleotoqlistre outieveryoq jpossiblere realitimeoscenarioqwhile

verifyingz DUT......w.....w......w......t.....e.....s.....t......b.....e.....n.....c.....h......i.....n

Ifiweo etryi toolistqoutre theiscenarios,oq jthenre weimayomissqsome

ofz them.uySo,e ousingzx randomization, based on the specification, scenarios are generated

in a randomfashion.

Foriexample,o etoi generateoaqpacketre ofilengthoq jwhichre rangesifromoq0

toz9,u yine overilogzx {$random()} % 10 should be used.

Withithis,o epacketsi ofolengthqarere generatedirandomly.oq jwww.testbench.in

(Qi9)o eWhati isotheqsignificancere ofiseedoq jinre randomization?

Ans:

Seediiso eusedi toochangeqthere sequenceiofoq jrandomre numbersigenerated.

Theiseedo einitializesi otheqrandomre numberigenerator.oq j

Allitheo erandomi numbersowhichqarere generatedifromoq jre aiparticularoseedqvalue

canz beu yrecreatede ozx by giving the same seed.

Iniouro eregressions,i stimulusogenerationqisre doneirandomly.oq jRunningre theicompleteo

regressionqwill generatez sameu yrandome onumberszx if we use same seed.

Soiouro eregressioni usesotheqtimere ofitestoq jcasere simulationistartedoasqthe

seedz tou yrandome onumberzx generator, with this we are able to generate different stimulus

for each regressions.
http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/


4/22

(Qi10)o eWhati isotheqdifferencere betweenicodeoq jcoveragere andifunctionalocoverage?

Ans:www.testbench.in

Coverageiiso eusedi toocheckqwhetherre theiTestbenchoq jhasre satisfactoryiexercisedothe

qdesign orz not?u y

Codeicoverageo ewilli giveoinformationqaboutre howimanyoq jlinesre areiexecuted,ohowqm

any timesz expressions,u ybranchese oexecuted.zx This coverage is collected by the simulation

tools. Users use this coverage to reach those corner cases which are not hit by the random

testcases. Users have to write the directed testcases to reach the missing code coverage

areas.

Functionalicoverageo e,i byotheqnamere itselfi,oq jisre relateditootheqfunctionality

ofz theu ydesigne oandzx it is defined by the user. User will define the coverage points for the

functions to be covered in DUT. This is completely under user control.

Bothiofo ethemi haveoequalqimportancere initheoq jverification.re 100io0.000000unctional

qcoverage doesz notu ymeane othatzx the DUT is completely exercised and vice-versa.

Verification engineers will consider both coverages to measure the verification

progress......w.....w......w......t.....e.....s.....t......b.....e.....n.....c.....h......i.....n

(Qi11)o eIfi CodeoCoverageqisre 100%iandoq jfunctionalre coverageiisonot,qwhatdoesz itu ymeane o?

Ans:

Theireasono ecouldi beoanyqonere ofitheoq jfollowing.www.testbench.in

1)Userididnoto eexercisei allotheqscenarios.re Userineedoq jtore writeitestcasesotoqfill

thez functionalu ycoveragee oholes.

2)Thereicouldo ebei aobugqinre theifunctionaloq jcoveragere blockiwhichoisqnot

recordingz theu yexecutede oscenario.zx User need to debug to find and fix the issue.

(Qi12)o eIfi Functionalocoverageqisre 100%iandoq jcodere coverageiisonot,qthen

whatz doesu yite omean?

Ans:

1)iIfo etherei isoaqbugre initestoq jenvironment,re dueitoothisqtest

mayz falseuyPass.e oThezx functional coverage will hit due to this false pass but some of the

dut code may not get exercised.

2)iIfo ethei dutoisqare legacyicodeoq jre oriIP,oitqmay havez someu yusee olesszxblocks to

support extra functionality. Due to this code coverage will not be 100% achieved.
http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/


5/22

3)iIno emyi firstocompany,qre thereiwasoq jsomere useilessologicqwhich

didz notuygete oexercised.zx When I approached the RTL designer, he said that fixing this use

less code will break the whole design. So he did not fix it. In this situation , functional

coverage is 100%, but not the code coverage.

4)Myifriendso eexperience,i onceoRTLqdesignerre addediaoq jcodere foriaonewqfeature. z B

ecauseu yofe omisszx communication, my friend didnt know that RTL designer added this newfunctionality.

Whenimyo efriendi didotheqcodere coverage,iheoq jfoundre someiunexercisedologicqwhich

hez didntu yunderstoode oandzx approached RTL designer. Then they figured out that because

of miscommunication, they found a feature in the spec which was implemented, but not

verified.www.testbench.in

Iidonto ethinki ,opointq2)re canibeoq javoided.re Pointi1),o3)qand

4)z canu ybeeosolved.zx

(Qi13)o eWhati isotheqdifferencere betweenipassiveoq jmonitorre andiactiveomonitor.

Ans:

Monitorireportso ethei protocoloviolationqandre identifiesialloq jtheretransactions.iMonitors

oareqtwo types,z Passiveu yande oactive.zx Passive monitors do not drive any signals, all the

signals are inputs. Active monitors can drive the DUT signals. Sometimes this is also refered as

receiver. Monitor converts the state of the design and its outputs to a transaction abstraction

level so it can be stored in a 'score-boards' database to be checked later on. Monitor converts

the pin level activities in to high level......w.....w......w......t.....e.....s.....t......b.....e.....n.....c.....h......i.....n

(Qi14)o eIni simulationoenvironment,qunderre whaticonditionoq jthere simulationishouldoen

d?

Ans:

1)iPacketo ecounti match.

2)iError

3)iErroro ecountwww.testbench.in

4)iInterfaceo eidlei count

5)iGlobalo etimeout

(Qi15)o eWhati isoscoreboard?

Ans:

Theitermo eSCOREBOARDi isonotqwell-definedre initheoq jindustry.re Itisometimesorefersqto
http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/


6/22

thez storageu ydatae ostructurezx only, sometimes it includes the transfer function as well,

and sometimes it includes the comparison function. In vmm methodology, the term scoreboard

is used to refer to the entire dynamic response-checking structure.

(Qi16)o eHowi theotestqcasesre areiincludedoq jinre toisimulationoenvironment?Ans:

Thereiareo emultiplei waysotoqdore this.i

Twoiveryo esimplei stylesoareqdiscussedre inibelowoq jlink.Click on the below link

http://www.testbench.in/TB_29_HANDLING_TESTCASE_FILES.htmlwww.testbench.in

HANDLING TESTCASE FILES

A test case is a file that describes an input, action, or event and an expected response, to

determine if a feature of an application is working correctly. A test case should contain

particulars such as test case identifier, test case name, objective, test conditions/setup, input

data requirements, steps, and expected results.

Note that the process of developing test cases can help find problems in the requirements or

design of an application, since it requires completely thinking through the operation of the

application. For this reason, it's useful to prepare test cases early in the development cycle if

possible.

The following example contains testbench environment and has 2 test cases.

EXAMPLE: top.v

moduletop();

// DUT instance, clock generator and TB components

// some tasks

taskwrite()

begin

// some logic

end

endtask

taskread()

begin

// some logic

end
http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/TB_29_HANDLING_TESTCASE_FILES.htmlhttp://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/TB_29_HANDLING_TESTCASE_FILES.htmlhttp://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/


7/22

endtask

end

EXAMPLE: testcase_1.v

// Do 10 write operations


// Do 10 read operations

To test first test cases, We have to simulate the contents of top.v file and testcase_1.v file.

1) Take an instance of module TEST in top.v file. Define the module definition in test cases.

During compilation just use the following commands

for testcase_1.v file

comile_command top.v testcase_1.v


comile_command top.v testcase_2.v

EXAMPLE: top.v

moduletop();


// some tasks

taskwrite()

begin

// some logic

end

endtask

taskread()

begin

// some logic

end


8/22

endtask

// TEST case instance

TESTtst();

end



moduleTEST();

initial

repeat(10)

top.write();

endmodule



moduleTEST();

initial

repeat(10)top.read();

endmodule

2) use `include test.v file. This needs a small script to copy the testcase file to test file. The

compilation command is same. But copy command which copies the testcase to test.v file is

different.

During compilation just use the following commands


cp testcase_1 test.v

comile_command top.v test.v


cp testcase_2 test.v

comile_command top.v test.v


9/22

EXAMPLE: top.v

moduletop();


// some tasks

taskwrite()

begin

// some logic

end

endtask

taskread()

begin

// some logic

end

endtask

// incule test.v file

`includetest.v

end



initial

repeat(10)

top.write();



initial

repeat(10)

top.read();

2) With the above two approaches, for each test case, we have to do individual compilation. In

this method, compile once and use simulation command to test with individual test case.

This needs a small script to convert all the test cases to single intermediate file. compilation

command is same. During simulation by giving the test case file name, we can include


10/22

particular testcase.

During compilation just give following command

cat testcase_1.v > test.v

cat testcase_2.v > test.vcompile_command top.v test.v

During simulation ,

for each test case, use

run_command +testcase_1

run_coomand +testcase_2

EXAMPLE: top.v

moduletop();


// some tasks

taskwrite()

begin

// some logic

end

endtask

taskread()

begin

// some logic

end

endtask

// incule test.v file

`includetest.v

end



repeat(10)

top.write();



11/22


repeat(10)

top.read();

Intermediate file generated contains all the testcase contents with some extra logic as shown.

EXAMPLE: INTERMEDIATE FILE test.v

initial

begin

if($test$plusargs("testcase_1")

begin// testcase_1 contents


repeat(10)

top.write();

end

if($test$plusargs("testcase_2")

begin// testcase_2 contents


repeat(10)

top.read();end

end

(Qi17)o eWhati areotheqdifferentre waysitestcaseoq jarere includediforosimulationsq?

Ans:

1)Compileionce,o esimulatei multipleotimesqwithre differentitestcases:oq j.....w.....w......w......t.

....e.....s.....t......b.....e.....n.....c.....h......i.....n

CompileiTestbencho e+i Allotestcasesqatre onceiandoq jduringre theisimulation,ousingqthe

$plusargs,z selectu ythee ologiczx of a particular testcase and execute it.

Thisistyleo eisi suedoinqOVMre andiUVM.oq j

Thisistyleo eshouldi makeosureqthat,re whenitheoq jtestre isiexecutedofromqcommand

line,z u yonlye oTestbenchzx + required testcase should be compiled. Other wise, compiling all

the testcases will consume huge time.

Iniregression,o eCompilingi allotheqtestcasesre +itestbenchsoq jatre onceiwillosaveqtime.

2)Separateicompilation:www.testbench.in

iCompileo ethei testbenchoonce.qre Toirunoq jare testcase,icompileotheqtestcase
http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/


12/22

,z linku ythee otestcasezx to testbench compiled code and simulate.

3)Compileionce,o esimulatei once:o

iAllo etestcasesi withosimilarqconfigurationre settingiandoq jtestbenchre areicompiledoonce

qand simulatedz inu yonee osinglezx run. After executing each testcase logic, HARD reset

should be applied to DUT and BFMs, so that the simulation looks as if it started fresh for thenext testcase code.

Thisistyleo eisi usedoinqVMMre 1.2.ioq jThisre styleisavesolotqof timez inuyregressions.

4)Compileionce,o esimulatei multipleotimesqwithre differentidata:oq j

Inisomeo everificationi environments,otestcaseqcodere doesntineedoq jtore beicompiles.oT

estcaseqfile containsz someu ydatae owhichzx is read by testbench to create different

scenarios. Testcase file can be read using $fopen or $plusargs in Verilog.

Thereicouldo ebei manyomoreqwaysre toidooq jthis.re www.testbench.in

Ifiyouo eknowi somethingowhichqisre notimentionedoq jabovere ,ipleaseotakeqa

minutez tou ymaile oitzx [email protected]

.....w.....w......w......t.....e.....s.....t......b.....e.....n.....c.....h......i.....n

(Qi18)o eExplaini howomessagesqarere implementediinoq jyourre testbench?

Ans:

IniVMM/RVM/AVM/OVM/UVM/ERM/Truss&Tealo emethodologies,i omessageqhandlingre logicii

soq jpredefined.re Useicanouseqthese predefinedz messageuyservicese oandzx print

messages as required by testbench. If above methodology base classes are not used, then user

can define his own message handling logic.

Iihaveo edefinedi aosimpleqverilogre logic,ilookoq jforre MessageiControloSystemqtopic

inz theu ybelowe olinkClick on the below link

http://www.testbench.in/TB_23_DEBUGGING.htmlwww.testbench.in

(Qi19)o eWritei codeoforqclockre generator?

Ans:

regiclk;

initialiclko e=i 0;o

alwaysi#10o eclki =o~clk;q

(Qi20)o eHowi toopassqare valueitooq jtestbenchre fromicommandoline?Ans:Click on the below link
http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/mailto:[email protected]:[email protected]:[email protected]://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/TB_23_DEBUGGING.htmlhttp://www.testbench.in/TB_23_DEBUGGING.htmlhttp://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/TB_23_DEBUGGING.htmlhttp://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/mailto:[email protected]://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/http://www.testbench.in/


13/22

http://www.testbench.in/TB_22_COMPILATION_N_SIMULATION_SWITCHS.html

COMPILATION N SIMULATION SWITCHS

Compilation And Simulation Directives:

Conditional Compilation directive switches vs Simulation directive switches

Verilog has following conditional compiler directives.

ìfdef

èlse

èlsif

èndif

ìfndef

The ìfdef compiler directive checks for the definition of a text_macro_name. If the

text_macro_name is defined, then the lines following the ìfdef directive are included. If the

text_macro_name is not defined and an èlse directive exists, then this source is

compiled. The ìfndef compiler directive checks for the definition of a text_macro_name. If

the text_macro_name is not defined, then the lines following the ìfndef directive are

included. If the text_macro_name is defined and an èlse directive exists, then this source is

compiled. If the èlsif directive exists (instead of the èlse) the compiler checks for the

definition of the text_macro_name. If the name exists the lines following the èlsif directive

are included. The èlsif directive is equivalent to the compiler directive sequence èlse ìfdef

... èndif. This directive does not need a corresponding `

functional verification questions

Documents