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cornell-brg / pymtl

Python-based hardware modeling framework
BSD 3-Clause "New" or "Revised" License
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Support `s.connect()` with constant `Bits` object #126

Open cbatten opened 9 years ago

cbatten commented 9 years ago

It looks likes pymtl is unable to support using Bits objects as constants. For example, if we wish to connect a constant to an input port, pymtl will accept a constant literal, but not a bits object:

  # A left-shift

  s.lshift = LeftLogicalShifter( a_nbits, 1 )
  ...
  s.connect( Bits( 1, 1 ), s.lshift.shamt )

Causes py.test to complain:

E     AttributeError: 'Bits' object has no attribute '_signal'

However, using a constant literal, instead, causes no such error:

  # A left-shift

  s.lshift = LeftLogicalShifter( a_nbits, 1 )
  ...
  s.connect( 1, s.lshift.shamt )