packAddr :: Nibble -> Nibble -> Nibble -> Addr
packAddr a1 a2 a3 = sum [ fromIntegral a1 * 256
                        , fromIntegral a2 * 16
                        , fromIntegral a3
                        ]
packAddr :: Nibble -> Nibble -> Nibble -> Addr
packAddr a1 a2 a3 = sum [ fromIntegral a1 * 256
                        , fromIntegral a2 * 16
                        , fromIntegral a3
                        ]
packAddr a1 a2 a3 = sum [ fromIntegral a1 * 256
                        , fromIntegral a2 * 16
                        , fromIntegral a3
                        ]