Index: trunk/MagicSoft/Mars/mtrigger/MFTriggerPattern.cc
===================================================================
--- trunk/MagicSoft/Mars/mtrigger/MFTriggerPattern.cc	(revision 5867)
+++ trunk/MagicSoft/Mars/mtrigger/MFTriggerPattern.cc	(revision 5869)
@@ -27,5 +27,7 @@
 //   MFTriggerPattern
 //
-//  A Filter for testing the trigger performance using Trigger Pattern
+//  A Filter for testing the trigger performance using Trigger Pattern.
+//
+// For files before file version 5 the trigger pattern is set to 00000000.
 //
 /////////////////////////////////////////////////////////////////////////////
Index: trunk/MagicSoft/Mars/mtrigger/MTriggerPattern.cc
===================================================================
--- trunk/MagicSoft/Mars/mtrigger/MTriggerPattern.cc	(revision 5867)
+++ trunk/MagicSoft/Mars/mtrigger/MTriggerPattern.cc	(revision 5869)
@@ -38,4 +38,6 @@
 // class version number (ClassDef) and document your change HERE.
 //
+// For files before file version 5 the trigger pattern is set to 00000000.
+//
 /////////////////////////////////////////////////////////////////////////////
 #include "MTriggerPattern.h"
Index: trunk/MagicSoft/Mars/mtrigger/MTriggerPatternDecode.cc
===================================================================
--- trunk/MagicSoft/Mars/mtrigger/MTriggerPatternDecode.cc	(revision 5867)
+++ trunk/MagicSoft/Mars/mtrigger/MTriggerPatternDecode.cc	(revision 5869)
@@ -28,4 +28,7 @@
 //
 //  Decodes the trigger pattern from MRawEvtData into MTriggerPattern.
+//
+// For files before file version 5 the trigger pattern is set to 00000000.
+// This can be changed using the information about the file-type.
 //
 // Input:
@@ -91,6 +94,11 @@
 // --------------------------------------------------------------------------
 //
+// For files before file version 5 the trigger pattern is set to 00000000.
+// This can be changed using the information about the file-type.
+//
 Int_t MTriggerPatternDecode::Process()
 {
+    // No setting necessary because MTriggerPattern::reset() has
+    // been called just before
     if (fRunHeader->GetFormatVersion()<5)
         return kTRUE;