diff --git a/src/emucore/tia/frame-manager/AbstractFrameManager.cxx b/src/emucore/tia/frame-manager/AbstractFrameManager.cxx
index 4af10f647..0fdd50c58 100644
--- a/src/emucore/tia/frame-manager/AbstractFrameManager.cxx
+++ b/src/emucore/tia/frame-manager/AbstractFrameManager.cxx
@@ -18,19 +18,37 @@
 #include "AbstractFrameManager.hxx"
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-AbstractFrameManager::AbstractFrameManager() :
-  myIsRendering(false),
-  myVsync(false),
-  myVblank(false),
-  myCurrentFrameFinalLines(0),
-  myPreviousFrameFinalLines(0),
-  myTotalFrames(0),
-  myLayout(FrameLayout::ntsc),
-  myFrameRate(0),
-  myOnFrameComplete(0),
-  myOnFrameStart(0),
-  myOnRenderingStart(0)
-{}
+AbstractFrameManager::AbstractFrameManager()
+{
+  reset();
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void AbstractFrameManager::reset()
+{
+  myIsRendering = false;
+  myVsync = false;
+  myVblank = false;
+  myCurrentFrameTotalLines = 0;
+  myCurrentFrameFinalLines = 0;
+  myPreviousFrameFinalLines = 0;
+  myTotalFrames = 0;
+  myLayout = FrameLayout::ntsc;
+  myFrameRate = 0;
+  myOnFrameComplete = 0;
+  myOnFrameStart = 0;
+  myOnRenderingStart = 0;
+
+  onReset();
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void AbstractFrameManager::nextLine()
+{
+  myCurrentFrameTotalLines++;
+
+  onNextLine();
+}
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void AbstractFrameManager::setHandlers(
@@ -70,10 +88,11 @@ void AbstractFrameManager::notifyFrameStart()
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-void AbstractFrameManager::notifyFrameComplete(uInt32 finalScanlines)
+void AbstractFrameManager::notifyFrameComplete()
 {
   myPreviousFrameFinalLines = myCurrentFrameFinalLines;
-  myCurrentFrameFinalLines = finalScanlines;
+  myCurrentFrameFinalLines = myCurrentFrameTotalLines;
+  myCurrentFrameTotalLines = 0;
   myTotalFrames++;
 
   if (myOnFrameComplete) myOnFrameComplete();
diff --git a/src/emucore/tia/frame-manager/AbstractFrameManager.hxx b/src/emucore/tia/frame-manager/AbstractFrameManager.hxx
index f7d1a0e6b..54fc57c70 100644
--- a/src/emucore/tia/frame-manager/AbstractFrameManager.hxx
+++ b/src/emucore/tia/frame-manager/AbstractFrameManager.hxx
@@ -41,6 +41,10 @@ class AbstractFrameManager : public Serializable
       callback renderingStartCallback
     );
 
+    void reset();
+
+    void nextLine();
+
     void setVblank(bool vblank);
 
     void setVsync(bool vsync);
@@ -77,10 +81,6 @@ class AbstractFrameManager : public Serializable
 
   public:
 
-    virtual void reset() = 0;
-
-    virtual void nextLine() = 0;
-
     virtual uInt32 height() const = 0;
 
     virtual void setFixedHeight(uInt32 height) = 0;
@@ -109,6 +109,10 @@ class AbstractFrameManager : public Serializable
 
     virtual void onSetVsync() {}
 
+    virtual void onNextLine() {}
+
+    virtual void onReset() {}
+
     virtual bool onSave(Serializer& out) const { throw runtime_error("cannot be serialized"); }
 
     virtual bool onLoad(Serializer& in) { throw runtime_error("cannot be serialized"); }
@@ -117,7 +121,7 @@ class AbstractFrameManager : public Serializable
 
     void notifyFrameStart();
 
-    void notifyFrameComplete(uInt32 finalScanlines);
+    void notifyFrameComplete();
 
     void notifyRenderingStart();
 
@@ -129,6 +133,8 @@ class AbstractFrameManager : public Serializable
 
     bool myVblank;
 
+    uInt32 myCurrentFrameTotalLines;
+
     uInt32 myCurrentFrameFinalLines;
 
     uInt32 myPreviousFrameFinalLines;