Automatic Process-Oriented Asynchronous Control Unit Generation from Control Data Flow Graphs
Euiseok Kim, Jeong Gun Lee, Dong Ik Lee · IEICE Transactions on Fundamentals of Electronics Communications and Computer Sciences · 2001
SUMMARY Althoughmanysuccessfulasynchronouscontrolcircuitsynthesismethodsareavailable,itisstillunwieldytocon-ceiveanddescribethebehaviorsofanumberofcontrollerswhichconstitute a control unit of a target system manually. In thispaper, an automatic and systematic method to derive an effi-cient asynchronous control unit from a system specification, acontrol data flow graph (CDFG), is suggested. In order to ac-quireanasynchronouscontrolunitofacceptablequality,anewprocess-orientedmethodisproposed. Inthismethod,theresult-ing asynchronous control unit has complete separation of ‘exe-cutioncontrollers’and‘executionordercontrollers’accordingtothehierarchicaldecompositionofagivenCDFG.Thisdistributivefeatureleadstoasignificantimprovementinarea,performance,implementabilityandsynthesistimeforthederivedasynchronouscontrolunits. key words: automaticasynchronouscontrolunitgenera-tion,process-oriented,ontroldataowgraphs,signaltransitiongraphs 1. IntroductionInthelastdecade,manyasynchronouslogicsynthe-sismethodshavebeenstudiedandsuggestedtomeettheincreasedinterestinasynchronouscircuitdesign[1]. Althoughsomeofthemhavebeenimplementedasasynchronouslogicsynthesistoolssuccessfully[2]–[7],itremainsdifficulttoconceiveanddescribethebehaviorsforanumberofcontrollersconstitutingthecontrolunitofatargetsystemmanually. Forexam-ple,whenanasynchronoussystemspecificationofatargetsystemisfirstgiventoadesigner,hemustde-scribeandimplementtheasynchronouscontrolunitmanually,whichmayconsistoftensoforhundredsofasynchronouscontrollers.Moreover,anSTG,whichisamostfrequentlyusedandpopularspecificationlan-guageforasynchronouscontrollers,isnotuserfriendlyinouropinion.Therefore,wepresentawaytoderiveasetofSTGsautomaticallyfromagivenhigh-levelsys-temspecification,aCDFG,inordertoalleviatethede-signer’sburdenintermsofconceivingmanySTGsforanasynchronouscontrolunit. DerivedSTGsaresyn-thesizedintoasynchronouscontrollersconstitutingan