Boolean operations

Description

Most common boolean operators can be instantiated without the Inst constructor.

List

Boolean operators are listed below :

• And2 : q <= i0 & i1
• Or2 : q <= i0 | i1
• Xor2 : q <= i0 ^ i1
• Inv : q <= ~i0

Generators to instantiate

One can choose the generator to be used. Some methods are applied to the cell and set the generator used when using &, |, ^ and ~. The generators used by default are the ones from the virtual library.

Methods are :

• SetAnd
• SetOr
• SetXor
• SetNot

Example

class essai ( Model ) :

  def Interface ( self ) :
    self.A = SignalIn  ( "a", 4 )
    self.B = SignalIn  ( "b", 4 )
    self.B = SignalIn  ( "c", 4 )
    
    self.S = SignalOut ( "s", 4 )

    self.vdd = VddIn  ( "vdd" )
    self.vss = VssIn  ( "vss" )
	
  def Netlist ( self ) :

    self.S <= ( ~self.A & self.B ) | self.C

Errors

Some errors may occur :

• [Stratus ERROR] & : the nets must have the same lenght.
  When one uses boolean expressions, one has to check that the sizes of both nets are equivalent.
• [Stratus ERROR] : there is no alim.
  The cell being created does not have the alimentation nets. The instanciation is impossible.

See Also

Introduction Netlist Instanciation of a multiplexor Instanciation of a shifter Instanciation of a register Instanciation of constants Arithmetical operations Comparison operations