Extract signals needed for Helicity decoding.

  These signals are plus and minus signals, the MPS indicator, and
  the start of quartet indicator.  The time from the TI (with overflow
  detection) is also retrieved as this is needed when dealing with
  delayed helicity reporting.

  The helicity signals are in FADC250 channels.  The roc/slot/channel
  assignments for these signals are currently hardwired into the code.

src/THcHelicityReader.cxx

+//*-- Author :    Ole Hansen    August 2006
+// Extracted from Bob Michaels' THaHelicity CVS 1.19
+////////////////////////////////////////////////////////////////////////
+//
+// THcHelicityReader
+//
+////////////////////////////////////////////////////////////////////////
+
+#include "THcHelicityReader.h"
+#include "THaEvData.h"
+#include "TMath.h"
+#include "TError.h"
+#include "VarDef.h"
+#include "THaAnalysisObject.h"   // For LoadDB
+#include <iostream>
+#include <vector>
+#include "TH1F.h"
+
+using namespace std;
+
+//____________________________________________________________________
+THcHelicityReader::THcHelicityReader()
+  : fTITime(0), fTITime_last(0), fTITime_rollovers(0), 
+    fHaveROCs(kFALSE)
+{
+  // Default constructor
+  
+}
+//____________________________________________________________________
+THcHelicityReader::~THcHelicityReader() 
+{
+  // Destructor
+
+  // Histograms will be deleted by ROOT
+  // for( Int_t i = 0; i < NHISTR; ++i ) {
+  //   delete fHistoR[i];
+  // }
+}
+
+//____________________________________________________________________
+void THcHelicityReader::Clear( Option_t* ) 
+{
+  
+  fIsMPS = fIsQrt = fIsHelp = fIsHelm = kFALSE;
+
+}
+
+//_____________________________________________________________________________
+Int_t THcHelicityReader::ReadDatabase( const char* /*dbfilename*/,
+					    const char* /*prefix*/,
+					    const TDatime& /*date*/,
+					    int /*debug_flag*/ )
+{
+
+  // Eventually get these from the parameter file
+
+  SetROCinfo(kHel,2,14,9);
+  SetROCinfo(kHelm,2,14,8);
+  SetROCinfo(kMPS,2,14,10);
+  SetROCinfo(kQrt,2,14,7);
+  SetROCinfo(kTime,2,21,2);
+
+  return THaAnalysisObject::kOK;
+}
+
+//_____________________________________________________________________________
+void THcHelicityReader::Begin()
+{ 
+  // static const char* const here = "THcHelicityReader::Begin";
+  // cout<<here<<endl;
+
+  fTITime_last = 0;
+  fTITime = 0;
+  fTITime_rollovers = 0;
+
+  return;
+}
+//____________________________________________________________________
+void THcHelicityReader::End()
+{
+  // static const char* const here = "THcHelicityReader::End";
+  // cout<<here<<endl;
+
+  return;
+}
+//____________________________________________________________________
+Int_t THcHelicityReader::ReadData( const THaEvData& evdata ) 
+{
+  // Obtain the present data from the event for QWEAK helicity mode.
+
+  static const char* here = "THcHelicityReader::ReadData";
+
+  //  std::cout<<" kHel, kTime, kRing="<< kHel<<" "<<kTime<<" "<<kRing<<endl;
+  //     for (int jk=0; jk<3; jk++)
+  //     {
+  //       std::cout<<" which="<<jk
+  // 	       <<" roc="<<fROCinfo[jk].roc
+  // 	       <<" header="<<fROCinfo[jk].header
+  // 	       <<" index="<<fROCinfo[jk].index 
+  // 	       <<endl;
+  //     }
+  
+  //  std::cout<<" fHaveROCs="<<fHaveROCs<<endl;
+  if( !fHaveROCs ) {
+    ::Error( here, "ROC data (detector map) not properly set up." );
+    return -1;
+  }
+
+  // Get the TI Data
+  //  Int_t fTIType = evData.GetData(fTICrate, fTISlot, 0, 0);
+  //  Int_t fTIEvNum = evData.GetData(fTICrate, fTISlot, 1, 0);
+  UInt_t titime = (UInt_t) evdata.GetData(fROCinfo[kTime].roc,
+					  fROCinfo[kTime].slot,
+					  fROCinfo[kTime].index, 0);
+  //cout << fTITime_last << " " << titime << endl;
+  if(titime < fTITime_last) {
+    fTITime_rollovers++;
+  }
+  fTITime = titime + fTITime_rollovers*4294967296;
+  fTITime_last = titime;
+
+  const_cast<THaEvData&>(evdata).SetEvTime(fTITime);
+
+  // Get the helicity control signals.  These are from the pedestals
+  // acquired by FADC channels.
+
+  UInt_t helpraw = evdata.GetData(Decoder::kPulsePedestal,
+				  fROCinfo[kHel].roc,
+				  fROCinfo[kHel].slot,
+				  fROCinfo[kHel].index, 0);
+  UInt_t helmraw = evdata.GetData(Decoder::kPulsePedestal,
+				  fROCinfo[kHelm].roc,
+				  fROCinfo[kHelm].slot,
+				  fROCinfo[kHelm].index, 0);
+  UInt_t mpsraw = evdata.GetData(Decoder::kPulsePedestal,
+				  fROCinfo[kMPS].roc,
+				  fROCinfo[kMPS].slot,
+				  fROCinfo[kMPS].index, 0);
+  UInt_t qrtraw = evdata.GetData(Decoder::kPulsePedestal,
+				  fROCinfo[kQrt].roc,
+				  fROCinfo[kQrt].slot,
+				  fROCinfo[kQrt].index, 0);
+
+  fIsQrt = qrtraw > 1000;
+  fIsMPS = mpsraw > 1000;
+  fIsHelp = helpraw > 1000;
+  fIsHelm = helmraw > 1000;
+
+  return 0;
+}
+
+//TODO: this should not be needed once LoadDB can fill fROCinfo directly
+//____________________________________________________________________
+Int_t THcHelicityReader::SetROCinfo( EROC which, Int_t roc,
+				       Int_t slot, Int_t index )
+{
+
+  // Define source and offset of data.  Normally called by ReadDatabase
+  // of the detector that is a THcHelicityReader.
+  //
+  // "which" is one of  { kHel, kKelm, kQrt, kTime }.
+  // You must define at least the kHel and kTime ROCs.
+  // Returns <0 if parameter error, 0 if success
+
+  if( which<kHel || which>=kCount )
+    return -1;
+  if( roc <= 0 || roc > 255 )
+    return -2;
+
+  fROCinfo[which].roc    = roc;
+  fROCinfo[which].slot = slot;
+  fROCinfo[which].index  = index;
+
+  cout << "SetROCInfo: " << which << " " << fROCinfo[kHel].roc << " " << fROCinfo[kTime].roc << endl;
+  fHaveROCs = ( fROCinfo[kHel].roc > 0 && fROCinfo[kTime].roc > 0 );
+  
+  return 0;
+}
+
+//____________________________________________________________________
+ClassImp(THcHelicityReader)
+

src/THcHelicityReader.h

+#ifndef Podd_THcHelicityReader_h_
+#define Podd_THcHelicityReader_h_
+
+//////////////////////////////////////////////////////////////////////////
+//
+// THcHelicityReader
+//
+// Routines for decoding QWEAK helicity hardware
+//
+//////////////////////////////////////////////////////////////////////////
+
+#include "Rtypes.h"
+
+class THaEvData;
+class TDatime;
+class TH1F;
+
+class THcHelicityReader {
+  
+public:
+  THcHelicityReader();
+  virtual ~THcHelicityReader();
+  
+  void Print();
+
+  struct ROCinfo {
+    Int_t  roc;               // ROC to read out
+    Int_t  slot;            // Headers to search for (0 = ignore)
+    Int_t  index;             // Index into buffer
+  };
+  
+protected:
+
+  // Used by ReadDatabase
+  enum EROC { kHel = 0, kHelm, kMPS, kQrt, kTime, kCount };
+  Int_t SetROCinfo( EROC which, Int_t roc, Int_t slot, Int_t index );
+
+  virtual void  Clear( Option_t* opt="" );
+  virtual Int_t ReadData( const THaEvData& evdata );
+  Int_t         ReadDatabase( const char* dbfilename, const char* prefix,
+			      const TDatime& date, int debug_flag = 0 );
+  void Begin();
+  void End();
+
+  ULong64_t fTITime;
+  UInt_t fTITime_last;
+  UInt_t fTITime_rollovers;
+  
+  // Reported Helicity status for the event
+  Bool_t fIsMPS;
+  Bool_t fIsQrt;
+  Bool_t fIsHelp;
+  Bool_t fIsHelm;
+
+  ROCinfo  fROCinfo[kCount];
+
+  Int_t    fQWEAKDebug;          // Debug level
+  Bool_t   fHaveROCs;         // Required ROCs are defined
+  Bool_t   fNegGate;          // Invert polarity of gate, TO DO implement this functionality
+  static const Int_t NHISTR = 12;
+  //  TH1F*    fHistoR[12];  // Histograms
+
+private:
+
+  ClassDef(THcHelicityReader,0) // Helper class for reading QWEAK helicity data
+
+};
+
+#endif
+