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Manipulating a single Instance Iterations in Virtuoso

Battosai

 

I am trying to manipulate the parameters of a single instance of an array (I1<1024:1>). The instances contain a simple RC network and a current source modelling a rather complex circuit. All the instances are connected in series using a bus-notation. Now I need to add a unique delay to every single one of the current sources in order to simulate a propagating signal through this chain of instances.

My idea was to use a skill function to deduce the number of the instance and use it as a multiplier for a constant delay and add it as a parameter of the internal current source. This way all 1024 instances should have a unique delay that is a function of its instance number.

I am fairly new to Skill and seem to be stuck..I managed to access a single instance using ilInst~>name but this returns me the complete name i.e. I1<x>. That's about as far as I came..

Does anyone have experience with this kind of problem or any hints that might help?
Parents
  • Andrew Beckett

    Samuel,

    You appear to be creating a netlisting function using AMS netlisting functions (which are for the AMS cell-based netlister), but then using the netlist procedure for spectre (which uses the "nl" netlisting functions). So that's why it's not working.

    Personally I would do this using a schematic pcell, then you don't need to worry about different custom netlist procedures for different simulators - the schematic would work in all ADE netlisters (except AMS cell-based, but would work in AMS OSS/irun flow).

    Here's an example:

    let( (CellLibrary pcellId)
  CellLibrary = "training"
  unless( ddGetObj(CellLibrary)
     error("Couldn't open library %L" CellLibrary)
  )
  
  pcellId =  pcDefinePCell(
     list( ddGetObj(CellLibrary) "rnsd" "schematic" "schematic" )
     
     /****************************************************************************
     /*
     /* Default Parameters
     /*
     /***************************************************************************/
     (
        (ns "1")
     )
     
     let(( pcCV masterCv instName instId netP netM numInsts)
       
       /*************************************************************************
       /*
       /* Get parameter values
       /*
       /************************************************************************/
       pcCV = pcCellView
       
       ;; open master cell view
       masterCv = dbOpenCellViewByType( "analogLib" "res" "symbol" nil "r" )

       ;; create the nets
       netP=dbMakeNet(pcCV "PLUS")
       netM=dbMakeNet(pcCV "MINUS")

       ;; create the terminals
       dbCreateTerm(netP "PLUS" "inputOutput")
       dbCreateTerm(netM "MINUS" "inputOutput")

       numInsts=atoi(ns)
       when(numInsts<1 numInsts=1)
       for(inst 1 numInsts
          if(inst==1 then
             netP=dbMakeNet(pcCV "PLUS")
          else 
             netP=dbMakeNet(pcCV sprintf(nil "net%d" inst-1))
          ) ; if
          if(inst==numInsts then
             netM=dbMakeNet(pcCV "MINUS")
          else 
             netM=dbMakeNet(pcCV sprintf(nil "net%d" inst))
          )

          ;; create instance
          sprintf(instName "R%d" inst)
          instId = dbCreateInst( pcCV masterCv instName (0:0) "R0" )
          dbCreateProp(instId "r" "string" "pPar(\"r\")/pPar(\"ns\")")

          ;; create instTerms for the instance to connect it up
          dbCreateInstTerm(netP instId dbFindTermByName(masterCv "PLUS"))
          dbCreateInstTerm(netM instId dbFindTermByName(masterCv "MINUS"))

       ) ; for

       dbClose( masterCv )
       ;; Always return true
       t
     ) ; ** let **
  )
  ; not sure if below is really necessary
  dbSave(pcellId)
  dbClose( pcellId ) 
) ; ** let **

     

    Regards,

    Andrew.

Reply
  • Andrew Beckett

    Samuel,

    You appear to be creating a netlisting function using AMS netlisting functions (which are for the AMS cell-based netlister), but then using the netlist procedure for spectre (which uses the "nl" netlisting functions). So that's why it's not working.

    Personally I would do this using a schematic pcell, then you don't need to worry about different custom netlist procedures for different simulators - the schematic would work in all ADE netlisters (except AMS cell-based, but would work in AMS OSS/irun flow).

    Here's an example:

    let( (CellLibrary pcellId)
  CellLibrary = "training"
  unless( ddGetObj(CellLibrary)
     error("Couldn't open library %L" CellLibrary)
  )
  
  pcellId =  pcDefinePCell(
     list( ddGetObj(CellLibrary) "rnsd" "schematic" "schematic" )
     
     /****************************************************************************
     /*
     /* Default Parameters
     /*
     /***************************************************************************/
     (
        (ns "1")
     )
     
     let(( pcCV masterCv instName instId netP netM numInsts)
       
       /*************************************************************************
       /*
       /* Get parameter values
       /*
       /************************************************************************/
       pcCV = pcCellView
       
       ;; open master cell view
       masterCv = dbOpenCellViewByType( "analogLib" "res" "symbol" nil "r" )

       ;; create the nets
       netP=dbMakeNet(pcCV "PLUS")
       netM=dbMakeNet(pcCV "MINUS")

       ;; create the terminals
       dbCreateTerm(netP "PLUS" "inputOutput")
       dbCreateTerm(netM "MINUS" "inputOutput")

       numInsts=atoi(ns)
       when(numInsts<1 numInsts=1)
       for(inst 1 numInsts
          if(inst==1 then
             netP=dbMakeNet(pcCV "PLUS")
          else 
             netP=dbMakeNet(pcCV sprintf(nil "net%d" inst-1))
          ) ; if
          if(inst==numInsts then
             netM=dbMakeNet(pcCV "MINUS")
          else 
             netM=dbMakeNet(pcCV sprintf(nil "net%d" inst))
          )

          ;; create instance
          sprintf(instName "R%d" inst)
          instId = dbCreateInst( pcCV masterCv instName (0:0) "R0" )
          dbCreateProp(instId "r" "string" "pPar(\"r\")/pPar(\"ns\")")

          ;; create instTerms for the instance to connect it up
          dbCreateInstTerm(netP instId dbFindTermByName(masterCv "PLUS"))
          dbCreateInstTerm(netM instId dbFindTermByName(masterCv "MINUS"))

       ) ; for

       dbClose( masterCv )
       ;; Always return true
       t
     ) ; ** let **
  )
  ; not sure if below is really necessary
  dbSave(pcellId)
  dbClose( pcellId ) 
) ; ** let **

     

    Regards,

    Andrew.

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