From adb22f7b001f302d19a19e4d5b0e3df745cbbb1e Mon Sep 17 00:00:00 2001
From: urchlay <urchlay@8b62c5a3-ac7e-4cc8-8f21-d9a121418aba>
Date: Sat, 9 Jul 2005 15:19:24 +0000
Subject: [PATCH] Added detection for 3E carts. As it was, 3E carts would
 detect as 3F, so it's just one test (search for STA $3E in the image) to
 distinguish between the two. I still only have 3 3E images (notBD PAL and
 NTSC, and Armin's test cart), but all 3 are detected, at least. Autodetection
 isn't as important in Stella as it is in some other emulators, due to the
 stella.pro database, so I won't try to make this too smart for its own
 good...

git-svn-id: svn://svn.code.sf.net/p/stella/code/trunk@629 8b62c5a3-ac7e-4cc8-8f21-d9a121418aba
---
 stella/src/emucore/Cart.cxx | 26 ++++++++++++++++++++++----
 stella/src/emucore/Cart.hxx | 16 +++++++++++++---
 2 files changed, 35 insertions(+), 7 deletions(-)

diff --git a/stella/src/emucore/Cart.cxx b/stella/src/emucore/Cart.cxx
index 0787502ab..b044ff106 100644
--- a/stella/src/emucore/Cart.cxx
+++ b/stella/src/emucore/Cart.cxx
@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: Cart.cxx,v 1.13 2005-07-08 11:50:32 stephena Exp $
+// $Id: Cart.cxx,v 1.14 2005-07-09 15:19:24 urchlay Exp $
 //============================================================================
 
 #include <assert.h>
@@ -238,22 +238,40 @@ string Cartridge::autodetectType(const uInt8* image, uInt32 size)
     }
   }
 
+  /* The above logic was written long before 3E support existed. It will
+     detect a 3E cart as 3F. Let's remedy that situation: */
+
+  if(type == "3F" && isProbably3E(image, size))
+    type = "3E";
+
   return type;
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-bool Cartridge::isProbably3F(const uInt8* image, uInt32 size)
+int Cartridge::searchForBytes(const uInt8* image, uInt32 size, uInt8 byte1, uInt8 byte2)
 {
   uInt32 count = 0;
   for(uInt32 i = 0; i < size - 1; ++i)
   {
-    if((image[i] == 0x85) && (image[i + 1] == 0x3F))
+    if((image[i] == byte1) && (image[i + 1] == byte2))
     {
       ++count;
     }
   }
 
-  return (count > 2);
+  return count;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool Cartridge::isProbably3F(const uInt8* image, uInt32 size)
+{
+  return (searchForBytes(image, size, 0x85, 0x3F) > 2);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool Cartridge::isProbably3E(const uInt8* image, uInt32 size)
+{
+  return (searchForBytes(image, size, 0x85, 0x3E) > 2);
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
diff --git a/stella/src/emucore/Cart.hxx b/stella/src/emucore/Cart.hxx
index 0d7170a5f..38b18f6c0 100644
--- a/stella/src/emucore/Cart.hxx
+++ b/stella/src/emucore/Cart.hxx
@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: Cart.hxx,v 1.6 2005-06-28 01:15:17 urchlay Exp $
+// $Id: Cart.hxx,v 1.7 2005-07-09 15:19:24 urchlay Exp $
 //============================================================================
 
 #ifndef CARTRIDGE_HXX
@@ -31,7 +31,7 @@ class System;
   game and handles any bankswitching performed by the cartridge.
  
   @author  Bradford W. Mott
-  @version $Id: Cart.hxx,v 1.6 2005-06-28 01:15:17 urchlay Exp $
+  @version $Id: Cart.hxx,v 1.7 2005-07-09 15:19:24 urchlay Exp $
 */
 class Cartridge : public Device
 {
@@ -75,10 +75,20 @@ class Cartridge : public Device
     static string autodetectType(const uInt8* image, uInt32 size);
 
     /**
-      Returns true iff the image is probably a 3F bankswitching cartridge
+      Returns true if the image is probably a 3F bankswitching cartridge
     */
     static bool isProbably3F(const uInt8* image, uInt32 size);
 
+    /**
+      Returns true if the image is probably a 3E bankswitching cartridge
+    */
+    static bool isProbably3E(const uInt8* image, uInt32 size);
+
+    /**
+      Utility method used by isProbably3F and isProbably3E
+    */
+    static int searchForBytes(const uInt8* image, uInt32 size, uInt8 byte1, uInt8 byte2);
+
   private:
     // Copy constructor isn't supported by cartridges so make it private
     Cartridge(const Cartridge&);