diff --git a/stella/src/debugger/Debugger.cxx b/stella/src/debugger/Debugger.cxx
index 5fcb27687..0d822c3cc 100644
--- a/stella/src/debugger/Debugger.cxx
+++ b/stella/src/debugger/Debugger.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: Debugger.cxx,v 1.47 2005-07-02 21:15:22 stephena Exp $
+// $Id: Debugger.cxx,v 1.48 2005-07-03 00:53:58 stephena Exp $
 //============================================================================
 
 #include "bspf.hxx"
@@ -475,6 +475,8 @@ void Debugger::loadState(int state)
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 int Debugger::step()
 {
+  saveRegs();
+
   int cyc = mySystem->cycles();
   mySystem->m6502().execute(1);
   myTIAdebug->updateTIA();
@@ -499,6 +501,8 @@ int Debugger::trace()
 {
   // 32 is the 6502 JSR instruction:
   if(mySystem->peek(myDebugger->pc()) == 32) {
+    saveRegs();
+
     int cyc = mySystem->cycles();
     int targetPC = myDebugger->pc() + 3; // return address
     while(myDebugger->pc() != targetPC)
@@ -834,4 +838,3 @@ void Debugger::saveRegs() {
 	oldP = getPS();
 	oldPC = getPC();
 }
-
diff --git a/stella/src/emucore/FrameBuffer.cxx b/stella/src/emucore/FrameBuffer.cxx
index 2b8fb7801..d3f0ca154 100644
--- a/stella/src/emucore/FrameBuffer.cxx
+++ b/stella/src/emucore/FrameBuffer.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: FrameBuffer.cxx,v 1.50 2005-07-02 01:28:43 stephena Exp $
+// $Id: FrameBuffer.cxx,v 1.51 2005-07-03 00:53:59 stephena Exp $
 //============================================================================
 
 #include <sstream>
@@ -294,6 +294,17 @@ void FrameBuffer::refreshOverlay(bool now)
   if(now) update();
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FrameBuffer::advance(int frames)
+{
+  if(myOSystem->eventHandler().state() != EventHandler::S_DEBUGGER)
+    return;
+
+  theFrameAdvanceIndicator = frames;
+  while(theFrameAdvanceIndicator)
+    update();
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void FrameBuffer::showMessage(const string& message)
 {
diff --git a/stella/src/emucore/FrameBuffer.hxx b/stella/src/emucore/FrameBuffer.hxx
index ad14fec7a..6bc9a555a 100644
--- a/stella/src/emucore/FrameBuffer.hxx
+++ b/stella/src/emucore/FrameBuffer.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: FrameBuffer.hxx,v 1.44 2005-07-02 01:28:43 stephena Exp $
+// $Id: FrameBuffer.hxx,v 1.45 2005-07-03 00:53:59 stephena Exp $
 //============================================================================
 
 #ifndef FRAMEBUFFER_HXX
@@ -52,7 +52,7 @@ enum FrameStyle {
   All GUI elements (ala ScummVM) are drawn here as well.
 
   @author  Stephen Anthony
-  @version $Id: FrameBuffer.hxx,v 1.44 2005-07-02 01:28:43 stephena Exp $
+  @version $Id: FrameBuffer.hxx,v 1.45 2005-07-03 00:53:59 stephena Exp $
 */
 class FrameBuffer
 {
@@ -148,7 +148,7 @@ class FrameBuffer
     /**
       Indicates that the emulation should advance one frame.
     */
-    void advance(int frames) { theFrameAdvanceIndicator = frames; }
+    void advance(int frames);
 
     /**
       Toggles between fullscreen and window mode.
diff --git a/stella/src/gui/CpuWidget.cxx b/stella/src/gui/CpuWidget.cxx
index d889af8c0..b1b3f5c97 100644
--- a/stella/src/gui/CpuWidget.cxx
+++ b/stella/src/gui/CpuWidget.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: CpuWidget.cxx,v 1.8 2005-07-02 21:15:22 stephena Exp $
+// $Id: CpuWidget.cxx,v 1.9 2005-07-03 00:53:59 stephena Exp $
 //
 //   Based on code from ScummVM - Scumm Interpreter
 //   Copyright (C) 2002-2004 The ScummVM project
@@ -240,7 +240,9 @@ void CpuWidget::fillGrid()
   vlist.push_back(dbg.getX());
   vlist.push_back(dbg.getY());
 
-  myCpuGrid->setList(alist, vlist);
+  for(int i = 0; i < 6; ++i)  // FIXME - track changes in registers
+    changed.push_back(false);
+  myCpuGrid->setList(alist, vlist, changed);
 
   // Update the PS register booleans
   BoolArray b;
diff --git a/stella/src/gui/DataGridWidget.cxx b/stella/src/gui/DataGridWidget.cxx
index 4157bcf1b..df75bca66 100644
--- a/stella/src/gui/DataGridWidget.cxx
+++ b/stella/src/gui/DataGridWidget.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: DataGridWidget.cxx,v 1.6 2005-07-02 21:15:22 stephena Exp $
+// $Id: DataGridWidget.cxx,v 1.7 2005-07-03 00:53:59 stephena Exp $
 //
 //   Based on code from ScummVM - Scumm Interpreter
 //   Copyright (C) 2002-2004 The ScummVM project
@@ -64,30 +64,21 @@ DataGridWidget::~DataGridWidget()
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-void DataGridWidget::setList(const AddrList& alist, const ValueList& vlist)
+void DataGridWidget::setList(const AddrList& alist, const ValueList& vlist,
+                             const BoolArray& changed)
 {
   int size = vlist.size();  // assume the alist is the same size
   assert(size == _rows * _cols);
 
   _addrList.clear();
   _addrStringList.clear();
+  _valueList.clear();
   _valueStringList.clear();
   _changedList.clear();
 
-  // Check for any value changes since last time this method was called
-  if(_valueList.size() == 0)
-  {
-    for(int i = 0; i < size; ++i)
-      _changedList.push_back(false);
-  }
-  else
-  {
-    for(int i = 0; i < size; ++i)
-      _changedList.push_back(_valueList[i] != vlist[i]);
-  }
-  _valueList.clear();
-  _addrList  = alist;
-  _valueList = vlist;
+  _addrList    = alist;
+  _valueList   = vlist;
+  _changedList = changed;
 
   // An efficiency thing
   string temp;
diff --git a/stella/src/gui/DataGridWidget.hxx b/stella/src/gui/DataGridWidget.hxx
index d535f8629..bf1d35503 100644
--- a/stella/src/gui/DataGridWidget.hxx
+++ b/stella/src/gui/DataGridWidget.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: DataGridWidget.hxx,v 1.4 2005-07-02 21:15:22 stephena Exp $
+// $Id: DataGridWidget.hxx,v 1.5 2005-07-03 00:53:59 stephena Exp $
 //
 //   Based on code from ScummVM - Scumm Interpreter
 //   Copyright (C) 2002-2004 The ScummVM project
@@ -50,7 +50,8 @@ class DataGridWidget : public EditableWidget, public CommandSender
                    int colchars, int range, BaseFormat format = kBASE_DEFAULT);
     virtual ~DataGridWidget();
 
-    void setList(const AddrList& alist, const ValueList& vlist);
+    void setList(const AddrList& alist, const ValueList& vlist,
+                 const BoolArray& changed);
     void setSelectedValue(int value);
 
     int getSelectedAddr() const   { return _addrList[_selectedItem]; }
diff --git a/stella/src/gui/RamWidget.cxx b/stella/src/gui/RamWidget.cxx
index 71bec8ca9..f528e5095 100644
--- a/stella/src/gui/RamWidget.cxx
+++ b/stella/src/gui/RamWidget.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: RamWidget.cxx,v 1.11 2005-07-02 21:15:22 stephena Exp $
+// $Id: RamWidget.cxx,v 1.12 2005-07-03 00:53:59 stephena Exp $
 //
 //   Based on code from ScummVM - Scumm Interpreter
 //   Copyright (C) 2002-2004 The ScummVM project
@@ -231,12 +231,15 @@ void RamWidget::fillGrid()
 {
   AddrList alist;
   ValueList vlist;
+  BoolArray changed;
 
+  Debugger& dbg = instance()->debugger();
   for(unsigned int i = 0; i < kRamSize; i++)
   {
     alist.push_back(kRamStart + i);
-    vlist.push_back(instance()->debugger().readRAM(i));
+    vlist.push_back(dbg.readRAM(i));
+    changed.push_back(dbg.ramChanged(i));
   }
 
-  myRamGrid->setList(alist, vlist);
+  myRamGrid->setList(alist, vlist, changed);
 }