diff --git a/src/Mima/Instruction.hs b/src/Mima/Instruction.hs
index 51ac9c6..547115f 100644
--- a/src/Mima/Instruction.hs
+++ b/src/Mima/Instruction.hs
@@ -77,12 +77,6 @@ data Instruction
   | LargeInstruction !LargeOpcode !SmallValue
   deriving (Show, Eq)
 
-instance ToText Instruction where
-  toText (SmallInstruction oc lv) = T.justifyLeft 4 ' ' (toText oc) <> " " <> largeValueToDec lv
-  toText (LargeInstruction oc sv)
-    | sv == minBound = T.justifyLeft 4 ' ' (toText oc)
-    | otherwise      = T.justifyLeft 4 ' ' (toText oc) <> " " <> smallValueToDec sv
-
 wordToInstruction :: MimaWord -> Either T.Text Instruction
 wordToInstruction mw = if getSmallOpcode mw == 0xF
                        then parseLargeInstruction mw
@@ -99,7 +93,7 @@ parseSmallOpcode :: Word32 -> Either T.Text SmallOpcode
 parseSmallOpcode w = case smallOpcodeMap Map.!? w of
   Just oc -> pure oc
   Nothing -> Left $ "Unknown small opcode " <> T.pack (show w)
-                     <> " (" <> toHex 1 w <> ")"
+                     <> " (" <> integralToHex 1 w <> ")"
 
 parseLargeInstruction :: MimaWord -> Either T.Text Instruction
 parseLargeInstruction mw = do
@@ -112,4 +106,4 @@ parseLargeOpcode :: Word32 -> Either T.Text LargeOpcode
 parseLargeOpcode w = case largeOpcodeMap Map.!? w of
   Just oc -> pure oc
   Nothing -> Left $ "Unknown large opcode " <> T.pack (show w)
-                     <> " (" <> toHex 1 w <> ")"
+                     <> " (" <> integralToHex 1 w <> ")"
diff --git a/src/Mima/Util.hs b/src/Mima/Util.hs
index 80d9209..cb050f6 100644
--- a/src/Mima/Util.hs
+++ b/src/Mima/Util.hs
@@ -1,7 +1,11 @@
+{-# LANGUAGE OverloadedStrings #-}
+
 module Mima.Util
   ( ToText(..)
-  , toDec
-  , toHex
+  , HexLike(..)
+  , groupByTwoChars
+  , integralToDec
+  , integralToHex
   ) where
 
 import qualified Data.Text as T
@@ -20,8 +24,22 @@ import qualified Numeric as N
 class ToText a where
   toText :: a -> T.Text
 
-toDec :: (Integral a, Show a) => Int -> a -> T.Text
-toDec digits a = T.justifyRight digits ' ' $ T.pack $ show a
+class HexLike a where
+  toDec :: a -> T.Text
+  toHex :: a -> T.Text
 
-toHex :: (Integral a, Show a) => Int -> a -> T.Text
-toHex digits a = T.justifyRight digits '0' $ T.pack $ N.showHex a ""
+  toHexBytes :: a -> T.Text
+  toHexBytes = T.intercalate " " . groupByTwoChars . toHex
+
+groupByTwoChars :: T.Text -> [T.Text]
+groupByTwoChars = reverse . helper . T.unpack . T.reverse
+  where
+    helper (c1:c2:cs) = T.pack [c2, c1] : helper cs
+    helper [c] = [T.singleton c]
+    helper []  = []
+
+integralToDec :: (Integral a, Show a) => Int -> a -> T.Text
+integralToDec digits a = T.justifyRight digits ' ' $ T.pack $ show a
+
+integralToHex :: (Integral a, Show a) => Int -> a -> T.Text
+integralToHex digits a = T.justifyRight digits '0' $ T.pack $ N.showHex a ""
diff --git a/src/Mima/Word.hs b/src/Mima/Word.hs
index 07a59db..de8eabd 100644
--- a/src/Mima/Word.hs
+++ b/src/Mima/Word.hs
@@ -4,10 +4,6 @@ module Mima.Word
   ( topBit
   -- * 24-bit value
   , MimaWord
-  -- ** Formatting
-  , wordToHex
-  , wordToDec
-  , wordToHexDec
   -- ** Converting
   , bytesToWord
   , wordToBytes
@@ -23,10 +19,6 @@ module Mima.Word
   -- * 20-bit value
   , LargeValue
   , MimaAddress
-  -- ** Formatting
-  , largeValueToHex
-  , largeValueToDec
-  , largeValueToHexDec
   -- ** Converting
   , bytesToLargeValue
   , largeValueToBytes
@@ -35,10 +27,6 @@ module Mima.Word
   , addLargeValues
   -- * 16-bit value
   , SmallValue
-  -- ** Formatting
-  , smallValueToHex
-  , smallValueToDec
-  , smallValueToHexDec
   -- ** Converting
   , signedSmallValueToWord
   ) where
@@ -70,6 +58,11 @@ newtype WB t = WB { unWB :: t}
 instance (Show t) => Show (WB t) where
   show = show . unWB
 
+instance (HexLike t) => HexLike (WB t) where
+  toDec = toDec . unWB
+  toHex = toHex . unWB
+  toHexBytes = toHexBytes . unWB
+
 -- Kinda obvious, isn't it? :P
 instance (Word32Based t) => Word32Based (WB t) where
   usedBits = usedBits . unWB
@@ -146,17 +139,12 @@ instance Word32Based MimaWord_ where
   fromWord32 w = MimaWord_ $ w .&. 0xFFFFFF
   toWord32 (MimaWord_ w) = w
 
+instance HexLike MimaWord_ where
+  toDec = T.pack . show . toWord32
+  toHex = integralToHex 6 . toWord32
+
 instance Show MimaWord_ where
-  show mw = T.unpack $ "MimaWord_ 0x" <> toHex 6 (toWord32 mw)
-
-wordToHex :: MimaWord -> T.Text
-wordToHex = toHex 6 . toWord32
-
-wordToDec :: MimaWord -> T.Text
-wordToDec = toDec 8 . toWord32
-
-wordToHexDec :: MimaWord -> T.Text
-wordToHexDec mw = wordToHex mw <> " (" <> wordToDec mw <> ")"
+  show mw = T.unpack $ "MimaWord_ 0x" <> toHex mw
 
 bytesToWord :: Word8 -> Word8 -> Word8 -> MimaWord
 bytesToWord w1 w2 w3 =
@@ -204,17 +192,12 @@ instance Word32Based LargeValue_ where
   fromWord32 w = LargeValue_ $ w .&. 0xFFFFF
   toWord32 (LargeValue_ w) = w
 
+instance HexLike LargeValue_ where
+  toDec = T.pack . show . toWord32
+  toHex = integralToHex 5 . toWord32
+
 instance Show LargeValue_ where
-  show lv = T.unpack $ "LargeValue_ 0x" <> toHex 5 (toWord32 lv)
-
-largeValueToHex :: LargeValue -> T.Text
-largeValueToHex = toHex 5 . toWord32
-
-largeValueToDec :: LargeValue -> T.Text
-largeValueToDec = toDec 7 . toWord32
-
-largeValueToHexDec :: LargeValue -> T.Text
-largeValueToHexDec mw = largeValueToHex mw <> " (" <> largeValueToDec mw <> ")"
+  show lv = T.unpack $ "LargeValue_ 0x" <> toHex lv
 
 bytesToLargeValue :: Word8 -> Word8 -> Word8 -> LargeValue
 bytesToLargeValue w1 w2 w3 = getAddress $ bytesToWord w1 w2 w3
@@ -236,17 +219,12 @@ instance Word32Based SmallValue_ where
   fromWord32 w = SmallValue_ $ w .&. 0xFFFF
   toWord32 (SmallValue_ w) = w
 
+instance HexLike SmallValue_ where
+  toDec = T.pack . show . toWord32
+  toHex = integralToHex 5 . toWord32
+
 instance Show SmallValue_ where
-  show lv = T.unpack $ "SmallValue_ 0x" <> toHex 4 (toWord32 lv)
-
-smallValueToHex :: SmallValue -> T.Text
-smallValueToHex = toHex 4 . toWord32
-
-smallValueToDec :: SmallValue -> T.Text
-smallValueToDec = toDec 5 . toWord32
-
-smallValueToHexDec :: SmallValue -> T.Text
-smallValueToHexDec mw = smallValueToHex mw <> " (" <> smallValueToDec mw <> ")"
+  show sv = T.unpack $ "SmallValue_ 0x" <> toHex sv
 
 signedSmallValueToWord :: SmallValue -> MimaWord
 signedSmallValueToWord sv