From b6d9acaee674538160f566de7b0536b15799ac6a Mon Sep 17 00:00:00 2001
From: Thomas Jentzsch <tjentzsch@yahoo.de>
Date: Wed, 23 Feb 2022 21:53:32 +0100
Subject: [PATCH] fixed read access to write port if write port uses upper
 address range (fixes #878)

---
 src/emucore/CartEnhanced.cxx | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/emucore/CartEnhanced.cxx b/src/emucore/CartEnhanced.cxx
index 44936ea07..f8201ff62 100644
--- a/src/emucore/CartEnhanced.cxx
+++ b/src/emucore/CartEnhanced.cxx
@@ -178,7 +178,7 @@ uInt8 CartridgeEnhanced::peek(uInt16 address)
   {
     // This is a read access to a write port!
     // Reading from the write port triggers an unwanted write
-    return peekRAM(myRAM[address], peekAddress);
+    return peekRAM(myRAM[address - myWriteOffset], peekAddress);
   }
 
   return myImage[romAddressSegmentOffset(peekAddress) + (peekAddress & myBankMask)];