Added initial support for state loading and saving. The relevant methods

are in System.cxx, and can be accessed from the various ports through
the Console.

To save state, call theConsole->system.saveState(string filename, string
md5sum).  The filename should include the full path and can be anything.
The md5sum is obvious and is used to make sure that the filename is actually
a state file for the current ROM.

To load state, call theConsole->system().loadState(string filename, string
md5sum.  These variables have the same meaning as above.

For now, only the SDL port has access to these.  Support will be added for
all ports when I do some more testing.

I'd appreciate some bug reports, especially related to sound handing on
state load.


git-svn-id: svn://svn.code.sf.net/p/stella/code/trunk@93 8b62c5a3-ac7e-4cc8-8f21-d9a121418aba

stella/src/emucore/m6502/src/Device.hxx

@@ -13,13 +13,15 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: Device.hxx,v 1.1.1.1 2001-12-27 19:54:29 bwmott Exp $
+// $Id: Device.hxx,v 1.2 2002-05-13 19:10:25 stephena Exp $
 //============================================================================
 
 #ifndef DEVICE_HXX
 #define DEVICE_HXX
 
 class System;
+class Serializer;
+class Deserializer;
 
 #include "bspf.hxx"
 
@@ -28,7 +30,7 @@ class System;
   based system.
 
   @author  Bradford W. Mott
-  @version $Id: Device.hxx,v 1.1.1.1 2001-12-27 19:54:29 bwmott Exp $
+  @version $Id: Device.hxx,v 1.2 2002-05-13 19:10:25 stephena Exp $
 */
 class Device
 {
@@ -71,6 +73,22 @@ class Device
     */
     virtual void install(System& system) = 0;
 
+    /**
+      Saves the current state of this device to the given Serializer.
+
+      @param out The serializer device to save to.
+      @return The result of the save.  True on success, false on failure.
+    */
+    virtual bool save(Serializer& out) = 0;
+
+    /**
+      Loads the current state of this device from the given Deserializer.
+
+      @param in The deserializer device to load from.
+      @return The result of the load.  True on success, false on failure.
+    */
+    virtual bool load(Deserializer& in) = 0;
+
   public:
     /**
       Get the byte at the specified address

stella/src/emucore/m6502/src/M6502.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: M6502.hxx,v 1.1.1.1 2001-12-27 19:54:30 bwmott Exp $
+// $Id: M6502.hxx,v 1.2 2002-05-13 19:10:25 stephena Exp $
 //============================================================================
 
 #ifndef M6502_HXX
@@ -21,6 +21,8 @@
 
 class D6502;
 class M6502;
+class Serializer;
+class Deserializer;
 
 #include "bspf.hxx"
 #include "System.hxx"
@@ -31,7 +33,7 @@ class M6502;
   has a 64K addressing space.
 
   @author  Bradford W. Mott
-  @version $Id: M6502.hxx,v 1.1.1.1 2001-12-27 19:54:30 bwmott Exp $ 
+  @version $Id: M6502.hxx,v 1.2 2002-05-13 19:10:25 stephena Exp $ 
 */
 class M6502
 {
@@ -94,6 +96,29 @@ class M6502
     */
     virtual void nmi();
 
+    /**
+      Saves the current state of this device to the given Serializer.
+
+      @param out The serializer device to save to.
+      @return The result of the save.  True on success, false on failure.
+    */
+    virtual bool save(Serializer& out) = 0;
+
+    /**
+      Loads the current state of this device from the given Deserializer.
+
+      @param in The deserializer device to load from.
+      @return The result of the load.  True on success, false on failure.
+    */
+    virtual bool load(Deserializer& in) = 0;
+
+    /**
+      Get a null terminated string which is the processor's name (i.e. "M6532")
+
+      @return The name of the device
+    */
+    virtual const char* name() const = 0;
+
   public:
     /**
       Get the addressing mode of the specified instruction

stella/src/emucore/m6502/src/M6502Hi.cxx

@@ -13,10 +13,12 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: M6502Hi.cxx,v 1.1.1.1 2001-12-27 19:54:30 bwmott Exp $
+// $Id: M6502Hi.cxx,v 1.2 2002-05-13 19:10:25 stephena Exp $
 //============================================================================
 
 #include "M6502Hi.hxx"
+#include "Serializer.hxx"
+#include "Deserializer.hxx"
 
 #define debugStream cout
 
@@ -167,3 +169,100 @@ void M6502High::interruptHandler()
   myExecutionStatus &= ~(MaskableInterruptBit | NonmaskableInterruptBit);
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool M6502High::save(Serializer& out)
+{
+  string CPU = name();
+
+  try
+  {
+    out.putString(CPU);
+
+    out.putLong(A);    // Accumulator
+    out.putLong(X);    // X index register
+    out.putLong(Y);    // Y index register
+    out.putLong(SP);   // Stack Pointer
+    out.putLong(IR);   // Instruction register
+    out.putLong(PC);   // Program Counter
+
+    out.putBool(N);     // N flag for processor status register
+    out.putBool(V);     // V flag for processor status register
+    out.putBool(B);     // B flag for processor status register
+    out.putBool(D);     // D flag for processor status register
+    out.putBool(I);     // I flag for processor status register
+    out.putBool(notZ);  // Z flag complement for processor status register
+    out.putBool(C);     // C flag for processor status register
+
+    out.putLong(myExecutionStatus);
+
+    // Indicates the number of distinct memory accesses
+    out.putLong(myNumberOfDistinctAccesses);
+    // Indicates the last address which was accessed
+    out.putLong(myLastAddress);
+
+  }
+  catch(char *msg)
+  {
+    cerr << msg << endl;
+    return false;
+  }
+  catch(...)
+  {
+    cerr << "Unknown error in save state for " << CPU << endl;
+    return false;
+  }
+
+  return true;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool M6502High::load(Deserializer& in)
+{
+  string CPU = name();
+
+  try
+  {
+    if(in.getString() != CPU)
+      return false;
+
+    A = (uInt8) in.getLong();    // Accumulator
+    X = (uInt8) in.getLong();    // X index register
+    Y = (uInt8) in.getLong();    // Y index register
+    SP = (uInt8) in.getLong();   // Stack Pointer
+    IR = (uInt8) in.getLong();   // Instruction register
+    PC = (uInt16) in.getLong();  // Program Counter
+
+    N = in.getBool();     // N flag for processor status register
+    V = in.getBool();     // V flag for processor status register
+    B = in.getBool();     // B flag for processor status register
+    D = in.getBool();     // D flag for processor status register
+    I = in.getBool();     // I flag for processor status register
+    notZ = in.getBool();  // Z flag complement for processor status register
+    C = in.getBool();     // C flag for processor status register
+
+    myExecutionStatus = (uInt8) in.getLong();
+
+    // Indicates the number of distinct memory accesses
+    myNumberOfDistinctAccesses = (uInt32) in.getLong();
+    // Indicates the last address which was accessed
+    myLastAddress = (uInt16) in.getLong();
+  }
+  catch(char *msg)
+  {
+    cerr << msg << endl;
+    return false;
+  }
+  catch(...)
+  {
+    cerr << "Unknown error in load state for " << CPU << endl;
+    return false;
+  }
+
+  return true;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+const char* M6502High::name() const
+{
+  return "M6502High";
+}

stella/src/emucore/m6502/src/M6502Hi.hxx

@@ -13,13 +13,15 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: M6502Hi.hxx,v 1.1.1.1 2001-12-27 19:54:30 bwmott Exp $
+// $Id: M6502Hi.hxx,v 1.2 2002-05-13 19:10:25 stephena Exp $
 //============================================================================
 
 #ifndef M6502HIGH_HXX
 #define M6502HIGH_HXX
 
 class M6502High;
+class Serializer;
+class Deserializer;
 
 #include "bspf.hxx"
 #include "M6502.hxx"
@@ -33,7 +35,7 @@ class M6502High;
   effects and for games which are very time sensitive.
 
   @author  Bradford W. Mott
-  @version $Id: M6502Hi.hxx,v 1.1.1.1 2001-12-27 19:54:30 bwmott Exp $
+  @version $Id: M6502Hi.hxx,v 1.2 2002-05-13 19:10:25 stephena Exp $
 */
 class M6502High : public M6502
 {
@@ -62,6 +64,29 @@ class M6502High : public M6502
     */
     virtual bool execute(uInt32 number);
 
+    /**
+      Saves the current state of this device to the given Serializer.
+
+      @param out The serializer device to save to.
+      @return The result of the save.  True on success, false on failure.
+    */
+    virtual bool save(Serializer& out);
+
+    /**
+      Loads the current state of this device from the given Deserializer.
+
+      @param in The deserializer device to load from.
+      @return The result of the load.  True on success, false on failure.
+    */
+    virtual bool load(Deserializer& in);
+
+    /**
+      Get a null terminated string which is the processors's name (i.e. "M6532")
+
+      @return The name of the device
+    */
+    virtual const char* name() const;
+
   public:
     /**
       Get the number of memory accesses to distinct memory locations

stella/src/emucore/m6502/src/M6502Low.cxx

@@ -13,10 +13,12 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: M6502Low.cxx,v 1.1.1.1 2001-12-27 19:54:31 bwmott Exp $
+// $Id: M6502Low.cxx,v 1.2 2002-05-13 19:10:25 stephena Exp $
 //============================================================================
 
 #include "M6502Low.hxx"
+#include "Serializer.hxx"
+#include "Deserializer.hxx"
 
 #define debugStream cout
 
@@ -157,3 +159,89 @@ void M6502Low::interruptHandler()
   myExecutionStatus &= ~(MaskableInterruptBit | NonmaskableInterruptBit);
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool M6502Low::save(Serializer& out)
+{
+  string CPU = name();
+
+  try
+  {
+    out.putString(CPU);
+
+    out.putLong(A);    // Accumulator
+    out.putLong(X);    // X index register
+    out.putLong(Y);    // Y index register
+    out.putLong(SP);   // Stack Pointer
+    out.putLong(IR);   // Instruction register
+    out.putLong(PC);   // Program Counter
+
+    out.putBool(N);     // N flag for processor status register
+    out.putBool(V);     // V flag for processor status register
+    out.putBool(B);     // B flag for processor status register
+    out.putBool(D);     // D flag for processor status register
+    out.putBool(I);     // I flag for processor status register
+    out.putBool(notZ);  // Z flag complement for processor status register
+    out.putBool(C);     // C flag for processor status register
+
+    out.putLong(myExecutionStatus);
+  }
+  catch(char *msg)
+  {
+    cerr << msg << endl;
+    return false;
+  }
+  catch(...)
+  {
+    cerr << "Unknown error in save state for " << CPU << endl;
+    return false;
+  }
+
+  return true;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool M6502Low::load(Deserializer& in)
+{
+  string CPU = name();
+
+  try
+  {
+    if(in.getString() != CPU)
+      return false;
+
+    A = (uInt8) in.getLong();    // Accumulator
+    X = (uInt8) in.getLong();    // X index register
+    Y = (uInt8) in.getLong();    // Y index register
+    SP = (uInt8) in.getLong();   // Stack Pointer
+    IR = (uInt8) in.getLong();   // Instruction register
+    PC = (uInt16) in.getLong();  // Program Counter
+
+    N = in.getBool();     // N flag for processor status register
+    V = in.getBool();     // V flag for processor status register
+    B = in.getBool();     // B flag for processor status register
+    D = in.getBool();     // D flag for processor status register
+    I = in.getBool();     // I flag for processor status register
+    notZ = in.getBool();  // Z flag complement for processor status register
+    C = in.getBool();     // C flag for processor status register
+
+    myExecutionStatus = (uInt8) in.getLong();
+  }
+  catch(char *msg)
+  {
+    cerr << msg << endl;
+    return false;
+  }
+  catch(...)
+  {
+    cerr << "Unknown error in load state for " << CPU << endl;
+    return false;
+  }
+
+  return true;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+const char* M6502Low::name() const
+{
+  return "M6502Low";
+}

stella/src/emucore/m6502/src/M6502Low.hxx

@@ -13,13 +13,15 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: M6502Low.hxx,v 1.1.1.1 2001-12-27 19:54:31 bwmott Exp $
+// $Id: M6502Low.hxx,v 1.2 2002-05-13 19:10:25 stephena Exp $
 //============================================================================
 
 #ifndef M6507LOW_HXX
 #define M6507LOW_HXX
 
 class M6507Low;
+class Serializer;
+class Deserializer;
 
 #include "bspf.hxx"
 #include "M6502.hxx"
@@ -39,7 +41,7 @@ class M6507Low;
   better compatibility is neccessary use one of the other 6502 classes.
   
   @author  Bradford W. Mott
-  @version $Id: M6502Low.hxx,v 1.1.1.1 2001-12-27 19:54:31 bwmott Exp $
+  @version $Id: M6502Low.hxx,v 1.2 2002-05-13 19:10:25 stephena Exp $
 */
 class M6502Low : public M6502
 {
@@ -68,6 +70,29 @@ class M6502Low : public M6502
     */
     virtual bool execute(uInt32 number);
 
+    /**
+      Saves the current state of this device to the given Serializer.
+
+      @param out The serializer device to save to.
+      @return The result of the save.  True on success, false on failure.
+    */
+    virtual bool save(Serializer& out);
+
+    /**
+      Loads the current state of this device from the given Deserializer.
+
+      @param in The deserializer device to load from.
+      @return The result of the load.  True on success, false on failure.
+    */
+    virtual bool load(Deserializer& in);
+
+    /**
+      Get a null terminated string which is the processors's name (i.e. "M6532")
+
+      @return The name of the device
+    */
+    virtual const char* name() const;
+
   protected:
     /**
       Called after an interrupt has be requested using irq() or nmi()

stella/src/emucore/m6502/src/NullDev.cxx

@@ -13,10 +13,12 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: NullDev.cxx,v 1.1.1.1 2001-12-27 19:54:31 bwmott Exp $
+// $Id: NullDev.cxx,v 1.2 2002-05-13 19:10:25 stephena Exp $
 //============================================================================
 
 #include "NullDev.hxx"
+#include "Serializer.hxx"
+#include "Deserializer.hxx"
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 NullDevice::NullDevice()
@@ -58,3 +60,14 @@ void NullDevice::poke(uInt16 address, uInt8 value)
   cerr << hex << "NullDevice: poke(" << address << "," << value << ")" << endl;
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool NullDevice::save(Serializer& out)
+{
+  return true;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool NullDevice::load(Deserializer& in)
+{
+  return true;
+}

stella/src/emucore/m6502/src/NullDev.hxx

@@ -13,13 +13,15 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: NullDev.hxx,v 1.1.1.1 2001-12-27 19:54:31 bwmott Exp $
+// $Id: NullDev.hxx,v 1.2 2002-05-13 19:10:25 stephena Exp $
 //============================================================================
 
 #ifndef NULLDEVICE_HXX
 #define NULLDEVICE_HXX
 
 class System;
+class Serializer;
+class Deserializer;
 
 #include "bspf.hxx"
 #include "Device.hxx"
@@ -30,7 +32,7 @@ class System;
   holes in the address space (i.e. no real device attached). 
  
   @author  Bradford W. Mott
-  @version $Id: NullDev.hxx,v 1.1.1.1 2001-12-27 19:54:31 bwmott Exp $
+  @version $Id: NullDev.hxx,v 1.2 2002-05-13 19:10:25 stephena Exp $
 */
 class NullDevice : public Device
 {
@@ -66,6 +68,22 @@ class NullDevice : public Device
     */
     virtual void install(System& system);
 
+    /**
+      Saves the current state of this device to the given Serializer.
+
+      @param out The serializer device to save to.
+      @return The result of the save.  True on success, false on failure.
+    */
+    virtual bool save(Serializer& out);
+
+    /**
+      Loads the current state of this device from the given Deserializer.
+
+      @param in The deserializer device to load from.
+      @return The result of the load.  True on success, false on failure.
+    */
+    virtual bool load(Deserializer& in);
+
   public:
     /**
       Get the byte at the specified address

stella/src/emucore/m6502/src/System.cxx

@@ -13,13 +13,17 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: System.cxx,v 1.2 2001-12-30 18:36:02 bwmott Exp $
+// $Id: System.cxx,v 1.3 2002-05-13 19:10:25 stephena Exp $
 //============================================================================
 
 #include <assert.h>
+#include <iostream>
+
 #include "Device.hxx"
 #include "M6502.hxx"
 #include "System.hxx"
+#include "Serializer.hxx"
+#include "Deserializer.hxx"
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 System::System(uInt16 n, uInt16 m)
@@ -47,6 +51,10 @@ System::System(uInt16 n, uInt16 m)
   {
     setPageAccess(page, access);
   }
+
+  // Set up (de)serializer in case we are asked to save/load state
+  serializer = new Serializer();
+  deserializer = new Deserializer();
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
@@ -63,6 +71,12 @@ System::~System()
 
   // Free my page access table
   delete[] myPageAccessTable;
+
+  // Free the serializer stuff
+  if(serializer)
+    delete serializer;
+  if(deserializer)
+    delete deserializer;
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
@@ -71,7 +85,7 @@ void System::reset()
   // Reset system cycle counter
   resetCycles();
 
-  // Frist we reset the devices attached to myself
+  // First we reset the devices attached to myself
   for(uInt32 i = 0; i < myNumberOfDevices; ++i)
   {
     myDevices[i]->reset();
@@ -106,10 +120,60 @@ void System::attach(M6502* m6502)
   myM6502->install(*this);
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool System::save(Serializer& out)
+{
+  string name = "System";
+
+  try
+  {
+    out.putString(name);
+    out.putLong(myCycles);
+  }
+  catch(char *msg)
+  {
+    cerr << msg << endl;
+    return false;
+  }
+  catch(...)
+  {
+    cerr << "Unknown error in save state for " << name << endl;
+    return false;
+  }
+
+  return true;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool System::load(Deserializer& in)
+{
+  string name = "System";
+
+  try
+  {
+    if(in.getString() != name)
+      return false;
+
+    myCycles = (uInt32) in.getLong();
+  }
+  catch(char *msg)
+  {
+    cerr << msg << endl;
+    return false;
+  }
+  catch(...)
+  {
+    cerr << "Unknown error in load state for " << name << endl;
+    return false;
+  }
+
+  return true;
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void System::resetCycles()
 {
-  // Frist we let all of the device attached to me know about the reset
+  // First we let all of the device attached to me know about the reset
   for(uInt32 i = 0; i < myNumberOfDevices; ++i)
   {
     myDevices[i]->systemCyclesReset();
@@ -140,6 +204,67 @@ const System::PageAccess& System::getPageAccess(uInt16 page)
   return myPageAccessTable[page];
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+int System::saveState(string &fileName, string& md5sum)
+{
+  // Open the file as a new Serializer
+  if(!serializer->open(fileName))
+    return 2;
+
+  // Prepend the state file with the md5sum of this cartridge
+  // This is the first defensive check for an invalid state file
+  serializer->putString(md5sum);
+
+  // First save state for this system
+  if(!save(*serializer))
+    return 3;
+
+  // Next, save state for the CPU
+  if(!myM6502->save(*serializer))
+    return 3;
+
+  // Now save the state of each device
+  for(uInt32 i = 0; i < myNumberOfDevices; ++i)
+  {
+    if(!myDevices[i]->save(*serializer))
+      return 3;
+  }
+
+  serializer->close();
+  return 1;  // success
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+int System::loadState(string &fileName, string& md5sum)
+{
+  // Open the file as a new Deserializer
+  if(!deserializer->open(fileName))
+    return 2;
+
+  // Look at the beginning of the state file.  It should contain the md5sum
+  // of the current cartridge.  If it doesn't, this state file is invalid.
+  if(deserializer->getString() != md5sum)
+    return 3;
+
+  // First load state for this system
+  if(!load(*deserializer))
+    return 3;
+
+  // Next, load state for the CPU
+  if(!myM6502->load(*deserializer))
+    return 3;
+
+  // Now load the state of each device
+  for(uInt32 i = 0; i < myNumberOfDevices; ++i)
+  {
+    if(!myDevices[i]->load(*deserializer))
+      return 3;
+  }
+
+  deserializer->close();
+  return 1;  // success
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 System::System(const System& s)
     : myAddressMask(s.myAddressMask),
@@ -157,5 +282,3 @@ System& System::operator = (const System&)
 
   return *this;
 }
-
-

stella/src/emucore/m6502/src/System.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: System.hxx,v 1.2 2001-12-30 18:36:02 bwmott Exp $
+// $Id: System.hxx,v 1.3 2002-05-13 19:10:25 stephena Exp $
 //============================================================================
 
 #ifndef SYSTEM_HXX
@@ -22,6 +22,8 @@
 class Device;
 class M6502;
 class NullDevice;
+class Serializer;
+class Deserializer;
 
 #include "bspf.hxx"
 #include "Device.hxx"
@@ -44,7 +46,7 @@ class NullDevice;
         dynamic code for that page of memory.
 
   @author  Bradford W. Mott
-  @version $Id: System.hxx,v 1.2 2001-12-30 18:36:02 bwmott Exp $
+  @version $Id: System.hxx,v 1.3 2002-05-13 19:10:25 stephena Exp $
 */
 class System
 {
@@ -70,6 +72,22 @@ class System
     */
     void reset();
 
+    /**
+      Saves the current state of this system class to the given Serializer.
+
+      @param out The serializer device to save to.
+      @return The result of the save.  True on success, false on failure.
+    */
+    bool save(Serializer& out);
+
+    /**
+      Loads the current state of this system class from the given Deserializer.
+
+      @param in The deserializer device to load from.
+      @return The result of the load.  True on success, false on failure.
+    */
+    bool load(Deserializer& in);
+
   public:
     /**
       Attach the specified device and claim ownership of it.  The device 
@@ -87,6 +105,30 @@ class System
     */
     void attach(M6502* m6502);
 
+    /**
+      Saves the current state of Stella to the given file.  Calls
+      save on every device and CPU attached to this system.
+
+      @param out The serializer device to save to.
+      @return The result of the save.  Error codes as follows:
+              1  success
+              2  file could not be opened for read/write
+              3  invalid state file
+    */
+    int saveState(string& fileName, string& md5sum);
+
+    /**
+      Loads the current state of Stella from the given file.  Calls
+      load on every device and CPU attached to this system.
+
+      @param in The deserializer device to load from.
+      @return The result of the load.  Error codes as follows:
+              1  success
+              2  file could not be opened for read/write
+              3  invalid state file
+    */
+    int loadState(string& fileName, string& md5sum);
+
   public:
     /**
       Answer the 6502 microprocessor attached to the system.  If a
@@ -278,6 +320,12 @@ class System
     // The current state of the Data Bus
     uInt8 myDataBusState;
 
+    // The serializer for the system.  Used to save state.
+    Serializer* serializer;
+
+    // The deserializer for the system.  Used to load state.
+    Deserializer* deserializer;
+
   private:
     // Copy constructor isn't supported by this class so make it private
     System(const System&);
@@ -332,4 +380,3 @@ inline void System::poke(uInt16 addr, uInt8 value)
   myDataBusState = value;
 }
 #endif
-