# DpgenSff

- Name : DpgenSff - Static Flip-Flop Macro-Generator
- Synopsys :

      Generate ( 'DpgenSff', modelname
               , param = { 'nbit'       : n
                         , 'physical'   : True
                         , 'behavioral' : True
                         }
               )

- Description : Generates a n bits static flip-flop named `modelname`. The two latches of this flip-flop are static, i.e. each one is made of two interters looped together.
- Terminal Names :
  - wen : write enable (1 bit)
  - ck : clock signal (1 bit)
  - i0 : data input (`n` bits)
  - q : output (`n` bits)
  - vdd : power
  - vss : ground
- Parameters : Parameters are given in the map `param`.
  - nbit (mandatory) : Defines the size of the generator
  - physical (optional, default value : False) : In order to generate a layout
  - behavioral (optional, default value : False) : In order to generate a behavior
- How it works :
  - When wen is set to `one`, enables the writing of the flip-flop
- Example :

      from stratus import *

      class inst_sff ( Model ) :

        def Interface ( self ) :
          self.ck  = SignalIn  (  "ck", 1 )
          self.wen = SignalIn  ( "wen", 1 )
          self.i   = SignalIn  (   "i", 4 )
          self.o   = SignalOut (   "o", 4 )

          self.vdd = VddIn ( "vdd" )
          self.vss = VssIn ( "vss" )

        def Netlist ( self ) :
          Generate ( 'DpgenSff', 'sff_4'
                   , param = { 'nbit'     : 4
                             , 'physical' : True
                             }
                   )
          self.I = Inst ( 'sff_4', 'inst'
                        , map = { "wen" : self.wen
                                , "ck"  : self.ck
                                , "i0"  : self.i
                                ,  "q"  : self.o
                                , 'vdd' : self.vdd
                                , 'vss' : self.vss
                                }
                        )

        def Layout ( self ) :
          Place ( self.I, NOSYM, Ref(0, 0) )