{-# OPTIONS_GHC -XTypeSynonymInstances  #-}

-------------------------------------------------------------------------------
--  $Id: Components.hs#1 2009/10/01 10:31:09 REDMOND\\satnams $
-------------------------------------------------------------------------------

module Xilinx.Components
where
import Lava

-------------------------------------------------------------------------------

class Combinational m bit => Xilinx m bit where
  xorcy :: (bit, bit) -> m bit
  muxcy :: (bit, (bit, bit)) -> m bit

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instance Xilinx Out Wire where
  xorcy = xorcy_nl
  muxcy = muxcy_nl

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inv_nl :: Wire -> Out Wire
inv_nl = unary_gate (Gate Lut1 "inv" Unplaced (1,1) (UnaryGate not))

-------------------------------------------------------------------------------

and2_nl :: (Wire, Wire) -> Out Wire
and2_nl = binary_gate (Gate Lut2 "and2" Unplaced (1,1) (BinaryGate (&&)))

-------------------------------------------------------------------------------

or2_nl :: (Wire, Wire) -> Out Wire
or2_nl = binary_gate (Gate Lut2 "or2" Unplaced (1,1) (BinaryGate (||)))

-------------------------------------------------------------------------------

xor2_nl :: (Wire, Wire) -> Out Wire
xor2_nl = binary_gate (Gate Lut2 "xor2" Unplaced (1,1) (BinaryGate (/=)))

-------------------------------------------------------------------------------

nxor2_nl :: (Wire, Wire) -> Out Wire
nxor2_nl = binary_gate (Gate Lut2 "nxor2" Unplaced (1,1) (BinaryGate (==)))

-------------------------------------------------------------------------------

xorcy_nl :: (Wire, Wire) -> Out Wire
xorcy_nl
   = binary_gate (Gate (LeafGate ["li", "ci"] ["o"]) "xorcy" Unplaced (1,1) 
                     (BinaryGate (/=)))

-------------------------------------------------------------------------------

muxcy_nl :: (Wire, (Wire, Wire)) -> Out Wire
muxcy_nl (s, (di, ci)) 
 = three_input_gate (Gate (LeafGate ["s", "di", "ci"] ["o"]) "muxcy" 
                     Unplaced (1,1) (Gate3 muxcy_behav)) (s, di, ci)

-------------------------------------------------------------------------------

muxcy_behav :: Bool -> Bool -> Bool -> Bool
muxcy_behav s di ci
  = if s then ci
    else di

-------------------------------------------------------------------------------