L1GTEvmDigiToRaw.cc

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// this class header
#include "EventFilter/L1GlobalTriggerRawToDigi/interface/L1GTEvmDigiToRaw.h"
 
// system include files
#include <vector>
#include <iostream>
#include <iomanip>
 
// user include files
#include "DataFormats/FEDRawData/interface/FEDRawDataCollection.h"
#include "DataFormats/FEDRawData/interface/FEDNumbering.h"
 
#include "DataFormats/FEDRawData/interface/FEDHeader.h"
#include "DataFormats/FEDRawData/interface/FEDTrailer.h"
#include "FWCore/Utilities/interface/CRC16.h"
 
#include "DataFormats/L1GlobalTrigger/interface/L1GlobalTriggerReadoutSetup.h"
#include "DataFormats/L1GlobalTrigger/interface/L1GlobalTriggerEvmReadoutRecord.h"
 
#include "DataFormats/L1GlobalTrigger/interface/L1GtfeWord.h"
#include "DataFormats/L1GlobalTrigger/interface/L1GtfeExtWord.h"
#include "DataFormats/L1GlobalTrigger/interface/L1TcsWord.h"
#include "DataFormats/L1GlobalTrigger/interface/L1GtFdlWord.h"
 
#include "FWCore/MessageLogger/interface/MessageLogger.h"
#include "FWCore/MessageLogger/interface/MessageDrop.h"
 
#include "FWCore/Framework/interface/EventSetup.h"
#include "FWCore/Framework/interface/ESHandle.h"
 
#include "CondFormats/L1TObjects/interface/L1GtFwd.h"
#include "CondFormats/L1TObjects/interface/L1GtBoard.h"
 
#include "CondFormats/L1TObjects/interface/L1GtBoardMaps.h"
#include "CondFormats/DataRecord/interface/L1GtBoardMapsRcd.h"
 
// constructor(s)
L1GTEvmDigiToRaw::L1GTEvmDigiToRaw(const edm::ParameterSet& pSet)
    : m_evmGtFedId(pSet.getUntrackedParameter<int>("EvmGtFedId", FEDNumbering::MINTriggerGTPFEDID)),
      m_evmGtInputToken(consumes<L1GlobalTriggerEvmReadoutRecord>(pSet.getParameter<edm::InputTag>("EvmGtInputTag"))),
      m_evmGtInputTag(pSet.getParameter<edm::InputTag>("EvmGtInputTag")),
      m_activeBoardsMaskGt(pSet.getParameter<unsigned int>("ActiveBoardsMask")),
      m_totalBxInEvent(0),
      m_minBxInEvent(0),
      m_maxBxInEvent(),
      m_verbosity(pSet.getUntrackedParameter<int>("Verbosity", 0)),
      m_isDebugEnabled(edm::isDebugEnabled())
 
{
  LogDebug("L1GTEvmDigiToRaw") << "\nMask for active boards (hex format): " << std::hex
                               << std::setw(sizeof(m_activeBoardsMaskGt) * 2) << std::setfill('0')
                               << m_activeBoardsMaskGt << std::dec << std::setfill(' ')
                               << "\nInput tag for EVM GT record: " << m_evmGtInputTag
                               << "\nFED Id for EVM GT record: " << m_evmGtFedId << " \n"
                               << std::endl;
 
  //
  produces<FEDRawDataCollection>();
}
 
// member functions
 
// method called to produce the data
void L1GTEvmDigiToRaw::produce(edm::Event& iEvent, const edm::EventSetup& evSetup) {
  // define new FEDRawDataCollection
  // it contains ALL FEDs in an event
  std::unique_ptr<FEDRawDataCollection> allFedRawData(new FEDRawDataCollection);
 
  FEDRawData& gtRawData = allFedRawData->FEDData(m_evmGtFedId);
 
  // get records from EventSetup
 
  //  board maps
  edm::ESHandle<L1GtBoardMaps> l1GtBM;
  evSetup.get<L1GtBoardMapsRcd>().get(l1GtBM);
 
  const std::vector<L1GtBoard> boardMaps = l1GtBM->gtBoardMaps();
  int boardMapsSize = boardMaps.size();
 
  typedef std::vector<L1GtBoard>::const_iterator CItBoardMaps;
 
  // create an ordered vector for the GT EVM record
  // header (pos 0 in record) and trailer (last position in record)
  // not included, as they are not in board list
  std::vector<L1GtBoard> gtRecordMap;
  gtRecordMap.reserve(boardMapsSize);
 
  for (int iPos = 0; iPos < boardMapsSize; ++iPos) {
    for (CItBoardMaps itBoard = boardMaps.begin(); itBoard != boardMaps.end(); ++itBoard) {
      if (itBoard->gtPositionEvmRecord() == iPos) {
        gtRecordMap.push_back(*itBoard);
        break;
      }
    }
  }
 
  // get L1GlobalTriggerEvmReadoutRecord
  edm::Handle<L1GlobalTriggerEvmReadoutRecord> gtReadoutRecord;
  iEvent.getByToken(m_evmGtInputToken, gtReadoutRecord);
 
  if (!gtReadoutRecord.isValid()) {
    edm::LogWarning("L1GTEvmDigiToRaw") << "\nWarning: L1GlobalTriggerEvmReadoutRecord with input tag "
                                        << m_evmGtInputTag
                                        << "\nrequested in configuration, but not found in the event."
                                        << "\nQuit packing this event" << std::endl;
 
    // put the raw data in the event
    iEvent.put(std::move(allFedRawData));
 
    return;
  }
 
  if (m_verbosity && m_isDebugEnabled) {
    std::ostringstream myCoutStream;
    gtReadoutRecord->print(myCoutStream);
    LogTrace("L1GTEvmDigiToRaw") << "\n The following L1 GT EVM readout record will be packed.\n"
                                 << " Some boards could be disabled before packing,"
                                 << " see detailed board packing.\n"
                                 << myCoutStream.str() << "\n"
                                 << std::endl;
  }
 
  // get GTFE block
  L1GtfeExtWord gtfeBlock = gtReadoutRecord->gtfeWord();
 
  // get the number of Bx in the event for alternative 0 and alternative 1
  cms_uint16_t recordLength0 = gtfeBlock.recordLength();
  cms_uint16_t recordLength1 = gtfeBlock.recordLength1();
 
  // length of BST record (in bytes)
  m_bstLengthBytes = static_cast<int>(gtfeBlock.bstLengthBytes());
 
  // get list of active blocks from the GTFE block
  // and mask some blocks, if required
  // blocks not active are not written to the record
 
  cms_uint16_t activeBoardsGtInitial = gtfeBlock.activeBoards();
  cms_uint16_t altNrBxBoardInitial = gtfeBlock.altNrBxBoard();
 
  // mask some boards, if needed
 
  cms_uint16_t activeBoardsGt = activeBoardsGtInitial & m_activeBoardsMaskGt;
 
  if (m_verbosity && m_isDebugEnabled) {
    LogDebug("L1GTEvmDigiToRaw") << "\nActive boards before masking(hex format): " << std::hex
                                 << std::setw(sizeof(activeBoardsGtInitial) * 2) << std::setfill('0')
                                 << activeBoardsGtInitial << std::dec << std::setfill(' ')
                                 << "\nActive boards after masking(hex format):  " << std::hex
                                 << std::setw(sizeof(activeBoardsGt) * 2) << std::setfill('0') << activeBoardsGt
                                 << std::dec << std::setfill(' ') << " \n"
                                 << std::endl;
  }
 
  // get the size of the record
 
  unsigned int gtDataSize = 0;
 
  unsigned int headerSize = 8;
  gtDataSize += headerSize;
 
  for (CItBoardMaps itBoard = boardMaps.begin(); itBoard != boardMaps.end(); ++itBoard) {
    if (itBoard->gtBoardType() == GTFE) {
      gtDataSize += gtfeBlock.getSize();
      continue;
    }
 
    int iActiveBit = itBoard->gtBitEvmActiveBoards();
    bool activeBoardToPack = false;
 
    int altNrBxBoardVal = -1;
 
    if (iActiveBit >= 0) {
      activeBoardToPack = activeBoardsGt & (1 << iActiveBit);
 
      altNrBxBoardVal = (altNrBxBoardInitial & (1 << iActiveBit)) >> iActiveBit;
 
      if (altNrBxBoardVal == 1) {
        m_totalBxInEvent = recordLength1;
      } else if (altNrBxBoardVal == 0) {
        m_totalBxInEvent = recordLength0;
      } else {
        if (m_verbosity) {
          edm::LogWarning("L1GTEvmDigiToRaw")
              << "\n\nWARNING: Wrong value altNrBxBoardVal = " << altNrBxBoardVal << " for board " << std::hex
              << (itBoard->gtBoardId()) << std::dec << "\n  iActiveBit =            " << iActiveBit
              << "\n  altNrBxBoardInitial = 0x" << std::hex << altNrBxBoardInitial << std::dec
              << "\n  activeBoardsGt =      0x" << std::hex << activeBoardsGt << std::dec
              << "\n  activeBoardToPack =   " << activeBoardToPack << "\n Set altNrBxBoardVal tentatively to "
              << recordLength0 << "\n Job may crash or produce wrong results!\n\n"
              << std::endl;
        }
 
        m_totalBxInEvent = recordLength0;
      }
    } else {
      // board not in the ActiveBoards for the record
      continue;
    }
 
    if (activeBoardToPack) {
      switch (itBoard->gtBoardType()) {
        case GTFE: {
          // size already added;
        }
 
        break;
        case FDL: {
          L1GtFdlWord fdlBlock;
          gtDataSize += m_totalBxInEvent * fdlBlock.getSize();
        }
 
        break;
        case TCS: {
          L1TcsWord tcsBlock;
          gtDataSize += tcsBlock.getSize();
        }
 
        break;
        case TIM: {
          // not considered
        }
 
        break;
        default: {
          // do nothing, all blocks are given in GtBoardType enum
        }
 
        break;
      }
    }
  }
 
  unsigned int trailerSize = 8;
  gtDataSize += trailerSize;
 
  // resize, GT raw data record has variable length,
  // depending on active boards (read in GTFE)
  gtRawData.resize(gtDataSize);
 
  // ptrGt: pointer to the beginning of GT record in the raw data
 
  unsigned char* ptrGt = gtRawData.data();
  unsigned char* ptrGtBegin = gtRawData.data();
 
  if (m_verbosity && m_isDebugEnabled) {
    LogDebug("L1GTEvmDigiToRaw") << "\n Size of raw data: " << gtRawData.size() << "\n" << std::endl;
  }
 
  // ------- pack boards -------
 
  // pack header
  packHeader(ptrGt, iEvent);
  ptrGt += headerSize;  // advance with header size
 
  // loop over other blocks in the raw record, if they are active
 
  for (CItBoardMaps itBoard = gtRecordMap.begin(); itBoard != gtRecordMap.end(); ++itBoard) {
    if (itBoard->gtBoardType() == GTFE) {
      packGTFE(evSetup, ptrGt, gtfeBlock, activeBoardsGt);
 
      if (m_verbosity && m_isDebugEnabled) {
        std::ostringstream myCoutStream;
        gtfeBlock.print(myCoutStream);
        LogTrace("L1GTEvmDigiToRaw") << myCoutStream.str() << "\n" << std::endl;
      }
 
      ptrGt += gtfeBlock.getSize();  // advance with GTFE block size
 
      continue;
    }
 
    // pack modules other than GTFE if they are active
 
    int iActiveBit = itBoard->gtBitEvmActiveBoards();
    bool activeBoardToPack = false;
 
    int altNrBxBoardVal = -1;
 
    if (iActiveBit >= 0) {
      activeBoardToPack = activeBoardsGt & (1 << iActiveBit);
 
      altNrBxBoardVal = (altNrBxBoardInitial & (1 << iActiveBit)) >> iActiveBit;
 
      if (altNrBxBoardVal == 1) {
        m_totalBxInEvent = recordLength1;
      } else if (altNrBxBoardVal == 0) {
        m_totalBxInEvent = recordLength0;
      } else {
        if (m_verbosity) {
          edm::LogWarning("L1GTEvmDigiToRaw")
              << "\n\nWARNING: Wrong value altNrBxBoardVal = " << altNrBxBoardVal << " for board " << std::hex
              << (itBoard->gtBoardId()) << std::dec << "\n  iActiveBit =            " << iActiveBit
              << "\n  altNrBxBoardInitial = 0x" << std::hex << altNrBxBoardInitial << std::dec
              << "\n  activeBoardsGt =      0x" << std::hex << activeBoardsGt << std::dec
              << "\n  activeBoardToPack =   " << activeBoardToPack << "\n Set altNrBxBoardVal tentatively to "
              << recordLength0 << "\n Job may crash or produce wrong results!\n\n"
              << std::endl;
        }
 
        m_totalBxInEvent = recordLength0;
      }
 
      m_minBxInEvent = (m_totalBxInEvent + 1) / 2 - m_totalBxInEvent;
      m_maxBxInEvent = (m_totalBxInEvent + 1) / 2 - 1;
 
    } else {
      // board not in the ActiveBoards for the record
      continue;
    }
 
    if (activeBoardToPack) {
      if (m_verbosity && m_isDebugEnabled) {
        LogDebug("L1GTEvmDigiToRaw") << "\nBoard " << std::hex << "0x" << (itBoard->gtBoardId()) << std::dec
                                     << "\n  Number of bunch crosses in the record: " << m_totalBxInEvent << " = "
                                     << "[" << m_minBxInEvent << ", " << m_maxBxInEvent << "] BX\n"
                                     << std::endl;
      }
 
      // active board, pack it
      switch (itBoard->gtBoardType()) {
        case TCS: {
          L1TcsWord tcsBlock = gtReadoutRecord->tcsWord();
          packTCS(evSetup, ptrGt, tcsBlock);
 
          if (m_verbosity && m_isDebugEnabled) {
            std::ostringstream myCoutStream;
            tcsBlock.print(myCoutStream);
            LogTrace("L1GTEvmDigiToRaw") << myCoutStream.str() << "\n" << std::endl;
          }
 
          ptrGt += tcsBlock.getSize();  // advance with TCS block size
 
        } break;
        case FDL: {
          for (int iBxInEvent = m_minBxInEvent; iBxInEvent <= m_maxBxInEvent; ++iBxInEvent) {
            L1GtFdlWord fdlBlock = gtReadoutRecord->gtFdlWord(iBxInEvent);
            packFDL(evSetup, ptrGt, fdlBlock);
 
            if (m_verbosity && m_isDebugEnabled) {
              std::ostringstream myCoutStream;
              fdlBlock.print(myCoutStream);
              LogTrace("L1GTEvmDigiToRaw") << myCoutStream.str() << "\n" << std::endl;
            }
 
            ptrGt += fdlBlock.getSize();  // advance with FDL block size
          }
 
        } break;
        default: {
          // do nothing, all blocks are given in GtBoardType enum
          break;
        }
      }
    }
  }
 
  // pack trailer
  packTrailer(ptrGt, ptrGtBegin, gtDataSize);
 
  // put the raw data in the event
 
  iEvent.put(std::move(allFedRawData));
}
 
// pack header
void L1GTEvmDigiToRaw::packHeader(unsigned char* ptrGt, edm::Event& iEvent) {
  // TODO FIXME where from to get all numbers?
 
  // Event Trigger type identifier
  int triggerTypeVal = 0;
 
  // Level-1 event number generated by the TTC system
  int lvl1IdVal = iEvent.id().event();
 
  // The bunch crossing number
  int bxCross = iEvent.bunchCrossing();
  cms_uint16_t bxCrossHw = 0;
  if ((bxCross & 0xFFF) == bxCross) {
    bxCrossHw = static_cast<cms_uint16_t>(bxCross);
  } else {
    bxCrossHw = 0;  // Bx number too large, set to 0!
    if (m_verbosity && m_isDebugEnabled) {
      LogDebug("L1GTEvmDigiToRaw") << "\nBunch cross number [hex] = " << std::hex << bxCross
                                   << "\n  larger than 12 bits. Set to 0! \n"
                                   << std::dec << std::endl;
    }
  }
  int bxIdVal = bxCrossHw;
 
  // Identifier of the FED
  int sourceIdVal = m_evmGtFedId;
 
  // Version identifier of the FED data format
  int versionVal = 0;
 
  // 0 -> the current header word is the last one.
  // 1-> other header words can follow
  // (always 1 for ECAL)
  bool moreHeadersVal = false;
 
  FEDHeader gtFEDHeader(ptrGt);
 
  gtFEDHeader.set(ptrGt, triggerTypeVal, lvl1IdVal, bxIdVal, sourceIdVal, versionVal, moreHeadersVal);
}
 
// pack the GTFE block
void L1GTEvmDigiToRaw::packGTFE(const edm::EventSetup& evSetup,
                                unsigned char* ptrGt,
                                L1GtfeExtWord& gtfeBlock,
                                cms_uint16_t activeBoardsGtValue) {
  if (m_verbosity && m_isDebugEnabled) {
    LogDebug("L1GTEvmDigiToRaw") << "\nPacking GTFE \n" << std::endl;
  }
 
  int uLength = L1GlobalTriggerReadoutSetup::UnitLength;
 
  // initialize the required number of word64
  int nrWord64 = gtfeBlock.getSize() / uLength;
  std::vector<cms_uint64_t> tmpWord64;
  tmpWord64.resize(nrWord64);
 
  for (int iWord = 0; iWord < nrWord64; ++iWord) {
    tmpWord64[iWord] = 0x0000000000000000ULL;
  }
 
  // fill the values in the words
  for (int iWord = 0; iWord < nrWord64; ++iWord) {
    gtfeBlock.setBoardIdWord64(tmpWord64[iWord], iWord);
    gtfeBlock.setRecordLength1Word64(tmpWord64[iWord], iWord);
    gtfeBlock.setRecordLengthWord64(tmpWord64[iWord], iWord);
    gtfeBlock.setBxNrWord64(tmpWord64[iWord], iWord);
    gtfeBlock.setSetupVersionWord64(tmpWord64[iWord], iWord);
    gtfeBlock.setActiveBoardsWord64(tmpWord64[iWord], iWord, activeBoardsGtValue);
    gtfeBlock.setAltNrBxBoardWord64(tmpWord64[iWord], iWord);
    gtfeBlock.setTotalTriggerNrWord64(tmpWord64[iWord], iWord);
 
    for (int iBst = 0; iBst < m_bstLengthBytes; ++iBst) {
      gtfeBlock.setBstWord64(tmpWord64[iWord], iBst, iWord);
    }
  }
 
  // put the words in the FED record
 
  cms_uint64_t* pw = reinterpret_cast<cms_uint64_t*>(const_cast<unsigned char*>(ptrGt));
 
  for (int iWord = 0; iWord < nrWord64; ++iWord) {
    *pw++ = tmpWord64[iWord];
 
    if (m_verbosity && m_isDebugEnabled) {
      LogTrace("L1GTEvmDigiToRaw") << std::setw(4) << iWord << "  " << std::hex << std::setfill('0') << std::setw(16)
                                   << tmpWord64[iWord] << std::dec << std::setfill(' ') << std::endl;
    }
  }
}
 
// pack the TCS block
void L1GTEvmDigiToRaw::packTCS(const edm::EventSetup& evSetup, unsigned char* ptrGt, L1TcsWord& tcsBlock) {
  if (m_verbosity && m_isDebugEnabled) {
    LogDebug("L1GTEvmDigiToRaw") << "\nPacking TCS \n" << std::endl;
  }
 
  int uLength = L1GlobalTriggerReadoutSetup::UnitLength;
 
  // initialize the required number of word64
  int nrWord64 = tcsBlock.getSize() / uLength;
  std::vector<cms_uint64_t> tmpWord64;
  tmpWord64.resize(nrWord64);
 
  for (int iWord = 0; iWord < nrWord64; ++iWord) {
    tmpWord64[iWord] = 0x0000000000000000ULL;
  }
 
  // fill the values in the words
  for (int iWord = 0; iWord < nrWord64; ++iWord) {
    tcsBlock.setBoardIdWord64(tmpWord64[iWord], iWord);
    tcsBlock.setBxNrWord64(tmpWord64[iWord], iWord);
    tcsBlock.setDaqNrWord64(tmpWord64[iWord], iWord);
    tcsBlock.setTriggerTypeWord64(tmpWord64[iWord], iWord);
    tcsBlock.setStatusWord64(tmpWord64[iWord], iWord);
    tcsBlock.setLuminositySegmentNrWord64(tmpWord64[iWord], iWord);
 
    tcsBlock.setPartRunNrWord64(tmpWord64[iWord], iWord);
    tcsBlock.setAssignedPartitionsWord64(tmpWord64[iWord], iWord);
 
    tcsBlock.setPartTrigNrWord64(tmpWord64[iWord], iWord);
    tcsBlock.setEventNrWord64(tmpWord64[iWord], iWord);
 
    tcsBlock.setOrbitNrWord64(tmpWord64[iWord], iWord);
  }
 
  // put the words in the FED record
 
  cms_uint64_t* pw = reinterpret_cast<cms_uint64_t*>(const_cast<unsigned char*>(ptrGt));
 
  for (int iWord = 0; iWord < nrWord64; ++iWord) {
    *pw++ = tmpWord64[iWord];
 
    if (m_verbosity && m_isDebugEnabled) {
      LogTrace("L1GTEvmDigiToRaw") << std::setw(4) << iWord << "  " << std::hex << std::setfill('0') << std::setw(16)
                                   << tmpWord64[iWord] << std::dec << std::setfill(' ') << std::endl;
    }
  }
}
 
// pack the FDL block
void L1GTEvmDigiToRaw::packFDL(const edm::EventSetup& evSetup, unsigned char* ptrGt, L1GtFdlWord& fdlBlock) {
  if (m_verbosity && m_isDebugEnabled) {
    LogDebug("L1GTEvmDigiToRaw") << "\nPacking FDL \n" << std::endl;
  }
 
  int uLength = L1GlobalTriggerReadoutSetup::UnitLength;
 
  // initialize the required number of word64
  int nrWord64 = fdlBlock.getSize() / uLength;
  std::vector<cms_uint64_t> tmpWord64;
  tmpWord64.resize(nrWord64);
 
  for (int iWord = 0; iWord < nrWord64; ++iWord) {
    tmpWord64[iWord] = 0x0000000000000000ULL;
  }
 
  // fill the values in the words
  for (int iWord = 0; iWord < nrWord64; ++iWord) {
    fdlBlock.setBoardIdWord64(tmpWord64[iWord], iWord);
    fdlBlock.setBxInEventWord64(tmpWord64[iWord], iWord);
    fdlBlock.setBxNrWord64(tmpWord64[iWord], iWord);
    fdlBlock.setEventNrWord64(tmpWord64[iWord], iWord);
 
    fdlBlock.setGtTechnicalTriggerWordWord64(tmpWord64[iWord], iWord);
 
    fdlBlock.setGtDecisionWordAWord64(tmpWord64[iWord], iWord);
    fdlBlock.setGtDecisionWordBWord64(tmpWord64[iWord], iWord);
 
    fdlBlock.setGtDecisionWordExtendedWord64(tmpWord64[iWord], iWord);
 
    fdlBlock.setPhysicsDeclaredWord64(tmpWord64[iWord], iWord);
    fdlBlock.setGtPrescaleFactorIndexTechWord64(tmpWord64[iWord], iWord);
    fdlBlock.setGtPrescaleFactorIndexAlgoWord64(tmpWord64[iWord], iWord);
    fdlBlock.setNoAlgoWord64(tmpWord64[iWord], iWord);
    fdlBlock.setFinalORWord64(tmpWord64[iWord], iWord);
 
    fdlBlock.setOrbitNrWord64(tmpWord64[iWord], iWord);
    fdlBlock.setLumiSegmentNrWord64(tmpWord64[iWord], iWord);
    fdlBlock.setLocalBxNrWord64(tmpWord64[iWord], iWord);
  }
 
  // put the words in the FED record
 
  cms_uint64_t* pw = reinterpret_cast<cms_uint64_t*>(const_cast<unsigned char*>(ptrGt));
 
  for (int iWord = 0; iWord < nrWord64; ++iWord) {
    *pw++ = tmpWord64[iWord];
 
    if (m_verbosity && m_isDebugEnabled) {
      LogTrace("L1GTEvmDigiToRaw") << std::setw(4) << iWord << "  " << std::hex << std::setfill('0') << std::setw(16)
                                   << tmpWord64[iWord] << std::dec << std::setfill(' ') << std::endl;
    }
  }
}
 
// pack trailer
void L1GTEvmDigiToRaw::packTrailer(unsigned char* ptrGt, unsigned char* ptrGtBegin, int dataSize) {
  // TODO FIXME where from to get all numbers?
 
  // The length of the event fragment counted in 64-bit words including header and trailer
  int lengthVal = dataSize / 8;
 
  // Cyclic Redundancy Code of the event fragment including header and trailer
  int crcVal = evf::compute_crc(ptrGtBegin, dataSize);
 
  // Event fragment status information
  int evtStatusVal = 0;
 
  // Current value of the Trigger Throttling System bits.
  int ttsBitsVal = 0;
 
  // 0 -> the current trailer word is the last one.
  // 1-> other trailer words can follow
  // (always 0 for ECAL)
  bool moreTrailersVal = false;
 
  FEDTrailer gtFEDTrailer(ptrGt);
  gtFEDTrailer.set(ptrGt, lengthVal, crcVal, evtStatusVal, ttsBitsVal, moreTrailersVal);
}
 
// static class members