Add stateful alu (with empty state).

[matthijs/master-project/cλash.git] / Adders.hs

diff --git a/Adders.hs b/Adders.hs
index ce261668e48eb7a9afd5a8e05ddb4bd31f65edf0..ac93a3366db359f3fc368467fe7280320aece926 100644 (file)
--- a/Adders.hs
+++ b/Adders.hs
@@ -39,6 +39,14 @@ dff d s = (s', q)
     q = s
     s' = d
 
+type ShifterState = (Bit, Bit, Bit, Bit)
+shifter :: Bit -> ShifterState -> (ShifterState, Bit)
+shifter a s =
+  (s', o)
+  where
+    s' = (a, b, c, d)
+    (b, c, d, o) = s
+
 -- Combinatoric stateless no-carry adder
 -- A -> B -> S
 no_carry_adder :: (Bit, Bit) -> Bit