diff -r 62a1d3631dcb -r b1b049e28772 MiniDisplay/FutabaVfd.cpp
--- a/MiniDisplay/FutabaVfd.cpp	Tue May 27 22:14:29 2014 +0200
+++ b/MiniDisplay/FutabaVfd.cpp	Wed May 28 08:06:27 2014 +0200
@@ -131,7 +131,7 @@
 
 /**
 */
-void GP1212A01A::BitBlit(BitArray& aBitmap, int aSrcWidth, int aSrcHeight, int aTargetX, int aTargetY) const
+void GP1212A01A::BitBlit(const BitArray& aBitmap, int aSrcWidth, int aSrcHeight, int aTargetX, int aTargetY) const
 	{
 	//TODO: amend loop values so that we don't keep on looping past our frame buffer dimensions.
 	for (int i=0;i<aSrcWidth;i++)
@@ -443,4 +443,4 @@
 	Clear();
 	SwapBuffers();
 	Clear();
-	}
\ No newline at end of file
+	}