XSTUserGuideforVirtex-6
andSpartan-6Devices
UG687(v12.3)September21,2010
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XSTUserGuideforVirtex-6andSpartan-6Devices
2www.xilinx.comUG687(v12.3)September21,2010
Preface
AbouttheXSTUserGuideforVirtex-6
andSpartan-6Devices
NoteTheXSTUserGuideforVirtex-6andSpartan-6DevicesappliestoXilinx®Virtex®-6
andSpartan®-6devicesonly.ForinformationonusingXSTwithotherdevices,see
theXSTUserGuide.
TheXSTUserGuideforVirtex-6andSpartan-6Devicesisbothareferencebookanda
guidetomethodology.Thisguide:
•DescribestheXilinxSynthesisTechnology(XST)synthesistoolindetail,including
instructionsforrunningandcontrollingXST.
•DiscussescodingtechniquesfordesigningcircuitsusingaHardwareDescription
Language(HDL)
•Givesguidelinestoleveragebuilt-inoptimizationtechniquesandachievethebest
implementation.
Thischapterincludes:
•GuideContents
•Acronyms
•AdditionalResources
•Conventions
GuideContents
TheXSTUserGuideforVirtex-6andSpartan-6Devicesincludes:
•Chapter1,IntroductiontoXilinxSynthesisTechnology(XST),givesabriefsummary
oftheXilinxSynthesisTechnology(XST)synthesistool.
•Chapter2,CreatingandSynthesizinganXSTProject,helpsyougetstartedwithXST,
understandhowtocreateanHDLsynthesisproject,andhowtocontrolandrunXST.
•Chapter3,XSTVHDLLanguageSupport,explainshowXSTsupportstheVHSIC
HardwareDescriptionLanguage(VHDL),andprovidesdetailsonVHDLsupported
constructsandsynthesisoptions.
•Chapter4,XSTVerilogSupport,describesXSTsupportforVerilogconstructsand
metacomments.
•Chapter5,XSTBehavioralVerilogSupport,describesXSTsupportforBehavioral
Verilog.
•Chapter6,XSTMixedLanguageSupport,describeshowtorunanXSTproject
thatmixesVerilogandVHDLdesigns.
•Chapter7,XSTHDLCodingTechniques,givescodingexamplesfordigitallogic
circuits.
XSTUserGuideforVirtex-6andSpartan-6Devices
UG687(v12.3)September21,2010www.xilinx.com3
Preface:AbouttheXSTUserGuideforVirtex-6andSpartan-6Devices
•Chapter8,XSTFPGAOptimization,explainshowtouseconstraintstooptimize
FPGAdevices;explainsmacrogeneration;anddescribestheFPGAdeviceprimitive
support.
•Chapter9,XSTDesignConstraints,providesgeneralinformationaboutXSTdesign
constraints.
•Chapter10,XSTGeneralConstraints,discussesindividualXSTGeneralConstraints.
•Chapter11,XSTHardwareDescriptionLanguage(HDL)Constraints,discusses
individualXSTHardwareDescriptionLanguage(HDL)constraints.
•Chapter12,XSTFPGAConstraints(Non-Timing)discussesindividualXSTFPGA
constraints(non-timing).
•Chapter13,XSTTimingConstraints,discussesXSTtimingconstraints.
•Chapter14,XST-SupportedThird-PartyConstraints,discussesXST-supported
third-partyconstraints.
•Chapter15,XSTSynthesisReport,describestheXSTlogle.
•Chapter16,XSTNamingConventions,describesXSTnamingconventions.
Acronyms
Acronym
Meaning
HDL
HardwareDescriptionLanguage
VHDL
VHSICHardwareDescriptionLanguage
RTL
RegisterTransferLevel
LRM
LanguageReferenceManual
FSM
FiniteStateMachine
EDIF
ElectronicDataInterchangeFormat
LSO
LibrarySearchOrder
XST
Xilinx®SynthesisTechnology
XCF
XSTConstraintFile
Conventions
Thisdocumentusesthefollowingconventions.Anexampleillustrateseachconvention.
Typographical
Thefollowingtypographicalconventionsareusedinthisdocument:
XSTUserGuideforVirtex-6andSpartan-6Devices
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Preface:AbouttheXSTUserGuideforVirtex-6andSpartan-6Devices
ConventionMeaningorUseExample
Courierfont
Messages,prompts,and
programlesthatthesystem
displays
speedgrade:-100
Courierbold
Literalcommandsthatyou
enterinasyntacticalstatement
ngdbuilddesign_name
Helveticabold
Commandsthatyouselect
fromamenu
File>Open
Keyboardshortcuts
Ctrl+C
ItalicfontVariablesinasyntax
statementforwhichyou
mustsupplyvalues
ngdbuilddesign_name
ReferencestoothermanualsSeetheCommandLine
ToolsUserGuideformore
information.
EmphasisintextIfawireisdrawnsothatit
overlapsthepinofasymbol,
thetwonetsarenotconnected.
Squarebrackets[]Anoptionalentryor
parameter.However,in
busspecications,suchas
bus[7:0],theyarerequired.
ngdbuild[option_name]
design_name
Braces{}
Alistofitemsfromwhichyou
mustchooseoneormore
lowpwr={on|off}
Verticalbar|
Separatesitemsinalistof
choices
lowpwr={on|off}
VerticalellipsisRepetitivematerialthathas
beenomitted
IOB#1:Name=QOUT
IOB#2:Name=CLKIN
.
.
.
Horizontalellipsis...Repetitivematerialthathas
beenomitted
allowblock...
block_nameloc1loc2...locn;
OnlineDocument
Thefollowingconventionsareusedinthisdocument:
ConventionMeaningorUseExample
BluetextCross-referencelinkSeethesectionAdditional
Resourcesfordetails.
RefertoTitleFormatsin
Chapter1fordetails.
SeeFigure2-5intheVirtex®-6
Handbook.
AdditionalResources
Tondadditionaldocumentation,seetheXilinxwebsiteat:
XSTUserGuideforVirtex-6andSpartan-6Devices
UG687(v12.3)September21,2010www.xilinx.com5