Modify THcScalerEvtHandler

1) add error message if Time between sucessive reads is zero.
    This should never happen.

2) Add the event number of that scaler read to the Scaler root tree
   The tree variable is evNumber

src/THcScalerEvtHandler.cxx

@@ -103,7 +103,7 @@ Int_t THcScalerEvtHandler::End( THaRunBase* r)
     AnalyzeBuffer(rdata,kFALSE);
   }
   if (fDebugFile) *fDebugFile << "scaler tree ptr  "<<fScalerTree<<endl;
-
+    evNumberR = -1;
   if (fScalerTree) fScalerTree->Fill();
 
   fDelayedEvents.clear();	// Does this free the arrays?
@@ -207,6 +207,10 @@ Int_t THcScalerEvtHandler::Analyze(THaEvData *evdata)
     name = "evcount";
     tinfo = name + "/D";
     fScalerTree->Branch(name.Data(), &evcountR, tinfo.Data(), 4000);
+ 
+   name = "evNumber";
+    tinfo = name + "/D";
+    fScalerTree->Branch(name.Data(), &evNumberR, tinfo.Data(), 4000);
 
     for (size_t i = 0; i < scalerloc.size(); i++) {
       name = scalerloc[i]->name;
@@ -220,6 +224,7 @@ Int_t THcScalerEvtHandler::Analyze(THaEvData *evdata)
 
   if( evdata->GetEvType() == fDelayedType) { // Save this event for processing later
     Int_t evlen = evdata->GetEvLength();
+    
     UInt_t *datacopy = new UInt_t[evlen];
     fDelayedEvents.push_back(datacopy);
     for(Int_t i=0;i<evlen;i++) {
@@ -227,7 +232,9 @@ Int_t THcScalerEvtHandler::Analyze(THaEvData *evdata)
     }
     return 1;
   } else { 			// A normal event
-    if (fDebugFile) *fDebugFile<<"\n\nTHcScalerEvtHandler :: Debugging event type "<<dec<<evdata->GetEvType()<<endl<<endl;
+    if (fDebugFile) *fDebugFile<<"\n\nTHcScalerEvtHandler :: Debugging event type "<<dec<<evdata->GetEvType()<< " event num = " << evdata->GetEvNum() << endl<<endl;
+    evNumber=evdata->GetEvNum();
+    evNumberR = evNumber;
     Int_t ret;
     if((ret=AnalyzeBuffer(rdata,fOnlySyncEvents))) {
       if (fDebugFile) *fDebugFile << "scaler tree ptr  "<<fScalerTree<<endl;
@@ -344,6 +351,11 @@ Int_t THcScalerEvtHandler::AnalyzeBuffer(UInt_t* rdata, Bool_t onlysync)
   fTotalTime = (thisClock+(((Double_t) fClockOverflows)*kMaxUInt+fClockOverflows))/fClockFreq;
   fLastClock = thisClock;
   fDeltaTime= fTotalTime - fPrevTotalTime;
+  if (fDeltaTime==0) {
+    cout << " *******************   Severe Warning ****************************" << endl;
+    cout << " In THcScalerEvtHandler have found fDeltaTime is zero !!   " << endl;
+      cout << " ******************* Alert DAQ experts ****************************" << endl;
+  }
   fPrevTotalTime=fTotalTime;
   Int_t nscal=0;
   for (size_t i = 0; i < scalerloc.size(); i++)  {

src/THcScalerEvtHandler.h

@@ -65,6 +65,8 @@ private:
    char** fBCM_Name;
    UInt_t evcount;
    Double_t evcountR;
+   UInt_t evNumber;
+   Double_t evNumberR;
    Int_t Nvars, ifound, fNormIdx, nscalers;
    Double_t *dvars;
    UInt_t *dvars_prev_read;