ZXS: Machine: Add more aux funcs

getMainMemByte retrieves one byte from the main memory.

diff --git a/src/ZXS/Machine.hs b/src/ZXS/Machine.hs
index 3eaeff0..52842c4 100644 (file)
--- a/src/ZXS/Machine.hs
+++ b/src/ZXS/Machine.hs
@@ -1,6 +1,8 @@
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
 module ZXS.Machine where
 
+import Data.Word
+import Control.Monad.IO.Class (liftIO)
 import Control.Monad.State
 import Control.Applicative (Applicative)
 
@@ -33,6 +35,10 @@ type ZXS a = ZXST IO a
 getsCPU :: (CPU -> a) -> ZXS a
 getsCPU f = gets zxCPU >>= return . f
 
+getMainMemByte :: Word16 -> ZXS Word8
+getMainMemByte addr = gets zxMainMem
+                  >>= \ mem -> liftIO $ ramGetByte mem addr
+
 modifyCPU :: (CPU -> CPU) -> ZXS ()
 modifyCPU f = modify $ \ spc -> spc { zxCPU = f $ zxCPU spc }