Load/save from Harmony cart flash RAM is now supported for the FA2

bankswitch scheme (currently, only the 256 internal RAM is used).


git-svn-id: svn://svn.code.sf.net/p/stella/code/trunk@2439 8b62c5a3-ac7e-4cc8-8f21-d9a121418aba

Changes.txt

@@ -12,7 +12,7 @@
                                Release History
 ===========================================================================
 
-3.6 to 3.7: (April xx, 2012)
+3.6.1 to 3.7: (April xx, 2012)
 
   * Updated the CompuMate keyboard handler to recognize more keys on an
     actual keyboard, instead of having to remember the weird combinations
@@ -21,11 +21,23 @@
   * Added emulation for MindLink controller; the Bionic Breakthrough
     ROM now works.
 
+  * Updated FA2 bankswitch scheme (Star Castle) to emulate load/save
+    high score functionality to the Harmony cart flash RAM.
+
+  * Updated internal database for 'Juno First' ROMs; they will now use
+    an AtariVox/SaveKey when possible.
+
   * Updated included PNG library to latest stable version.
 
 -Have fun!
 
 
+3.6 to 3.6.1: (March 30, 2012)
+
+  * Extended FA2 bankswitch scheme to handle 28K ROMs (in addition to
+    the previously supported 24K ROMs).
+
+
 3.5.5 to 3.6: (March 16, 2012)
 
   * Added support for 2600-daptor II device, including native support

src/emucore/Cart.cxx

@@ -62,7 +62,7 @@
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 Cartridge* Cartridge::create(const uInt8* image, uInt32 size, string& md5,
-     string& dtype, string& id, Settings& settings)
+     string& dtype, string& id, const OSystem& system, Settings& settings)
 {
   Cartridge* cartridge = 0;
   string type = dtype;
@@ -177,7 +177,8 @@ Cartridge* Cartridge::create(const uInt8* image, uInt32 size, string& md5,
   else if(type == "FA" || type == "FASC")
     cartridge = new CartridgeFA(image, size, settings);
   else if(type == "FA2")
-    cartridge = new CartridgeFA2(image, size, settings);
+    cartridge = new CartridgeFA2(image, size, settings,
+                    system.eepromDir() + "FA2_flash.dat");
   else if(type == "FE")
     cartridge = new CartridgeFE(image, size, settings);
   else if(type == "MC")

src/emucore/Cart.hxx

@@ -61,11 +61,13 @@ class Cartridge : public Device
       @param dtype    The detected bankswitch type of the ROM image
       @param id       Any extra info about the ROM (currently which part
                       of a multiload game is being accessed
+      @param system   The osystem associated with the system
       @param settings The settings associated with the system
       @return   Pointer to the new cartridge object allocated on the heap
     */
     static Cartridge* create(const uInt8* image, uInt32 size, string& md5,
-                             string& dtype, string& id, Settings& settings);
+                             string& dtype, string& id,
+                             const OSystem& system, Settings& settings);
 
     /**
       Create a new cartridge

src/emucore/CartFA2.cxx

@@ -20,12 +20,16 @@
 #include <cassert>
 #include <cstring>
 
+#include "Serializer.hxx"
 #include "System.hxx"
 #include "CartFA2.hxx"
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-CartridgeFA2::CartridgeFA2(const uInt8* image, uInt32 size, const Settings& settings)
+CartridgeFA2::CartridgeFA2(const uInt8* image, uInt32 size,
+                           const Settings& settings, const string& flashfile)
   : Cartridge(settings),
+    myRamRWFlag(false),
+    myFlashFile(flashfile),
     mySize(size)
 {
   // Allocate array for the ROM image
@@ -106,6 +110,12 @@ uInt8 CartridgeFA2::peek(uInt16 address)
   // Switch banks if necessary
   switch(address)
   {
+    case 0x0FF4:
+      // Load/save RAM to/from Harmony cart flash
+      if(mySize == 28*1024 && !bankLocked())
+        return ramReadWrite();
+      break;
+
     case 0x0FF5:
       // Set the current bank to the first 4k bank
       bank(0);
@@ -171,6 +181,12 @@ bool CartridgeFA2::poke(uInt16 address, uInt8)
   // Switch banks if necessary
   switch(address)
   {
+    case 0x0FF4:
+      // Load/save RAM to/from Harmony cart flash
+      if(mySize == 28*1024 && !bankLocked())
+        ramReadWrite();
+      break;
+
     case 0x0FF5:
       // Set the current bank to the first 4k bank
       bank(0);
@@ -231,14 +247,14 @@ bool CartridgeFA2::bank(uInt16 bank)
   System::PageAccess access(0, 0, 0, this, System::PA_READ);
 
   // Set the page accessing methods for the hot spots
-  for(uInt32 i = (0x1FF5 & ~mask); i < 0x2000; i += (1 << shift))
+  for(uInt32 i = (0x1FF4 & ~mask); i < 0x2000; i += (1 << shift))
   {
     access.codeAccessBase = &myCodeAccessBase[offset + (i & 0x0FFF)];
     mySystem->setPageAccess(i >> shift, access);
   }
 
   // Setup the page access methods for the current bank
-  for(uInt32 address = 0x1200; address < (0x1FF5U & ~mask);
+  for(uInt32 address = 0x1200; address < (0x1FF4U & ~mask);
       address += (1 << shift))
   {
     access.directPeekBase = &myImage[offset + (address & 0x0FFF)];
@@ -332,3 +348,58 @@ bool CartridgeFA2::load(Serializer& in)
 
   return true;
 }
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+uInt8 CartridgeFA2::ramReadWrite()
+{
+  /* The following algorithm implements accessing Harmony cart flash
+
+    1. Wait for an access to hotspot location $1FF4 (return 1 on first access).
+
+    2. Read byte 256 of RAM+ memory to determine the operation requested
+       (1 = read, 2 = write).
+
+    3. Save or load the entire 256 bytes of RAM+ memory to a file.
+
+    4. Set byte 256 of RAM+ memory to zero to indicate success.
+
+    5. Return 0 on the next access to $1FF4.
+  */
+  if(!myRamRWFlag)
+  {
+    Serializer serializer(myFlashFile);
+    if(serializer.isValid())
+    {
+      if(myRAM[255] == 1)       // read
+      {
+        try
+        {
+          for(uInt32 i = 0; i < 256; ++i)
+            myRAM[i] = (uInt8) serializer.getByte();
+        }
+        catch(const char* msg)
+        {
+          memset(myRAM, 0, 256);
+        }
+      }
+      else if(myRAM[255] == 2)  // write
+      {
+        try
+        {
+          for(uInt32 i = 0; i < 256; ++i)
+            serializer.putByte((char)myRAM[i]);
+        }
+        catch(const char* msg)
+        {
+          // Maybe add logging here?
+        }
+      }
+    }
+    return 1;
+  }
+  else
+  {
+    myRamRWFlag = false;
+    return 0;
+  }
+}

src/emucore/CartFA2.hxx

@@ -43,8 +43,10 @@ class CartridgeFA2 : public Cartridge
       @param image     Pointer to the ROM image
       @param size      The size of the ROM image
       @param settings  A reference to the various settings (read-only)
+      @param flashfile The full pathname for the flash file storing internal RAM
     */
-    CartridgeFA2(const uInt8* image, uInt32 size, const Settings& settings);
+    CartridgeFA2(const uInt8* image, uInt32 size, const Settings& settings,
+                 const string& flashfile);
  
     /**
       Destructor
@@ -139,6 +141,13 @@ class CartridgeFA2 : public Cartridge
     */
     bool poke(uInt16 address, uInt8 value);
 
+  private:
+    /**
+      Either load or save internal RAM to Harmony flash (represented by
+      a file in emulation).
+    */
+    uInt8 ramReadWrite();
+
   private:
     // Indicates which bank is currently active
     uInt16 myCurrentBank;
@@ -149,6 +158,13 @@ class CartridgeFA2 : public Cartridge
     // The 256 bytes of RAM on the cartridge
     uInt8 myRAM[256];
 
+    // An access has been made to load/save internal RAM
+    bool myRamRWFlag;
+
+    // Full pathname of the file to use when emulating load/save
+    // of internal RAM to Harmony cart flash
+    string myFlashFile;
+
     // Size of the ROM image
     uInt32 mySize;
 };

src/emucore/OSystem.cxx

@@ -693,7 +693,7 @@ Console* OSystem::openConsole(const string& romfile, string& md5,
     string cartmd5 = md5;
     type = props.get(Cartridge_Type);
     Cartridge* cart =
-      Cartridge::create(image, size, cartmd5, type, id, *mySettings);
+      Cartridge::create(image, size, cartmd5, type, id, *this, *mySettings);
 
     // It's possible that the cart created was from a piece of the image,
     // and that the md5 (and hence the cart) has changed