CSCCathodeLCTProcessor.cc

#include "L1Trigger/CSCTriggerPrimitives/interface/CSCCathodeLCTProcessor.h"

#include <iomanip>
#include <iostream>

// Default values of configuration parameters.
const unsigned int CSCCathodeLCTProcessor::def_fifo_tbins = 12;
const unsigned int CSCCathodeLCTProcessor::def_fifo_pretrig = 7;
const unsigned int CSCCathodeLCTProcessor::def_hit_persist = 6;
const unsigned int CSCCathodeLCTProcessor::def_drift_delay = 2;
const unsigned int CSCCathodeLCTProcessor::def_nplanes_hit_pretrig = 2;
const unsigned int CSCCathodeLCTProcessor::def_nplanes_hit_pattern = 4;
const unsigned int CSCCathodeLCTProcessor::def_pid_thresh_pretrig = 2;
const unsigned int CSCCathodeLCTProcessor::def_min_separation = 10;
const unsigned int CSCCathodeLCTProcessor::def_tmb_l1a_window_size = 7;

//----------------
// Constructors --
//----------------

CSCCathodeLCTProcessor::CSCCathodeLCTProcessor(unsigned endcap,
                                               unsigned station,
                                               unsigned sector,
                                               unsigned subsector,
                                               unsigned chamber,
                                               const edm::ParameterSet& conf)
    : CSCBaseboard(endcap, station, sector, subsector, chamber, conf) {
  static std::atomic<bool> config_dumped{false};

  // CLCT configuration parameters.
  fifo_tbins = clctParams_.getParameter<unsigned int>("clctFifoTbins");
  hit_persist = clctParams_.getParameter<unsigned int>("clctHitPersist");
  drift_delay = clctParams_.getParameter<unsigned int>("clctDriftDelay");
  nplanes_hit_pretrig = clctParams_.getParameter<unsigned int>("clctNplanesHitPretrig");
  nplanes_hit_pattern = clctParams_.getParameter<unsigned int>("clctNplanesHitPattern");

  // Not used yet.
  fifo_pretrig = clctParams_.getParameter<unsigned int>("clctFifoPretrig");

  pid_thresh_pretrig = clctParams_.getParameter<unsigned int>("clctPidThreshPretrig");
  min_separation = clctParams_.getParameter<unsigned int>("clctMinSeparation");

  start_bx_shift = clctParams_.getParameter<int>("clctStartBxShift");

  // Motherboard parameters: common for all configurations.
  tmb_l1a_window_size =  // Common to CLCT and TMB
      tmbParams_.getParameter<unsigned int>("tmbL1aWindowSize");

  // separate handle for early time bins
  early_tbins = tmbParams_.getParameter<int>("tmbEarlyTbins");
  if (early_tbins < 0)
    early_tbins = fifo_pretrig - CSCConstants::CLCT_EMUL_TIME_OFFSET;

  // wether to readout only the earliest two LCTs in readout window
  readout_earliest_2 = tmbParams_.getParameter<bool>("tmbReadoutEarliest2");

  // Verbosity level, set to 0 (no print) by default.
  infoV = clctParams_.getParameter<int>("verbosity");

  // Check and print configuration parameters.
  checkConfigParameters();
  if ((infoV > 0) && !config_dumped) {
    dumpConfigParams();
    config_dumped = true;
  }

  numStrips = 0;  // Will be set later.
  // Provisional, but should be OK for all stations except ME1.
  for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++) {
    if ((i_layer + 1) % 2 == 0)
      stagger[i_layer] = 0;
    else
      stagger[i_layer] = 1;
  }

  thePreTriggerDigis.clear();
}

CSCCathodeLCTProcessor::CSCCathodeLCTProcessor() : CSCBaseboard() {
  // constructor for debugging.
  static std::atomic<bool> config_dumped{false};

  // CLCT configuration parameters.
  setDefaultConfigParameters();
  infoV = 2;

  early_tbins = 4;

  start_bx_shift = 0;

  // Check and print configuration parameters.
  checkConfigParameters();
  if (!config_dumped) {
    dumpConfigParams();
    config_dumped = true;
  }

  numStrips = CSCConstants::MAX_NUM_STRIPS;
  // Should be OK for all stations except ME1.
  for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++) {
    if ((i_layer + 1) % 2 == 0)
      stagger[i_layer] = 0;
    else
      stagger[i_layer] = 1;
  }

  thePreTriggerDigis.clear();
}

void CSCCathodeLCTProcessor::setDefaultConfigParameters() {
  // Set default values for configuration parameters.
  fifo_tbins = def_fifo_tbins;
  fifo_pretrig = def_fifo_pretrig;
  hit_persist = def_hit_persist;
  drift_delay = def_drift_delay;
  nplanes_hit_pretrig = def_nplanes_hit_pretrig;
  nplanes_hit_pattern = def_nplanes_hit_pattern;
  pid_thresh_pretrig = def_pid_thresh_pretrig;
  min_separation = def_min_separation;
  tmb_l1a_window_size = def_tmb_l1a_window_size;
}

// Set configuration parameters obtained via EventSetup mechanism.
void CSCCathodeLCTProcessor::setConfigParameters(const CSCDBL1TPParameters* conf) {
  static std::atomic<bool> config_dumped{false};

  fifo_tbins = conf->clctFifoTbins();
  fifo_pretrig = conf->clctFifoPretrig();
  hit_persist = conf->clctHitPersist();
  drift_delay = conf->clctDriftDelay();
  nplanes_hit_pretrig = conf->clctNplanesHitPretrig();
  nplanes_hit_pattern = conf->clctNplanesHitPattern();
  pid_thresh_pretrig = conf->clctPidThreshPretrig();
  min_separation = conf->clctMinSeparation();

  // Check and print configuration parameters.
  checkConfigParameters();
  if (!config_dumped) {
    dumpConfigParams();
    config_dumped = true;
  }
}

void CSCCathodeLCTProcessor::checkConfigParameters() {
  // Make sure that the parameter values are within the allowed range.

  // Max expected values.
  static const unsigned int max_fifo_tbins = 1 << 5;
  static const unsigned int max_fifo_pretrig = 1 << 5;
  static const unsigned int max_hit_persist = 1 << 4;
  static const unsigned int max_drift_delay = 1 << 2;
  static const unsigned int max_nplanes_hit_pretrig = 1 << 3;
  static const unsigned int max_nplanes_hit_pattern = 1 << 3;
  static const unsigned int max_pid_thresh_pretrig = 1 << 4;
  static const unsigned int max_min_separation = CSCConstants::NUM_HALF_STRIPS_7CFEBS;
  static const unsigned int max_tmb_l1a_window_size = 1 << 4;

  // Checks.
  CSCBaseboard::checkConfigParameters(fifo_tbins, max_fifo_tbins, def_fifo_tbins, "fifo_tbins");
  CSCBaseboard::checkConfigParameters(fifo_pretrig, max_fifo_pretrig, def_fifo_pretrig, "fifo_pretrig");
  CSCBaseboard::checkConfigParameters(hit_persist, max_hit_persist, def_hit_persist, "hit_persist");
  CSCBaseboard::checkConfigParameters(drift_delay, max_drift_delay, def_drift_delay, "drift_delay");
  CSCBaseboard::checkConfigParameters(
      nplanes_hit_pretrig, max_nplanes_hit_pretrig, def_nplanes_hit_pretrig, "nplanes_hit_pretrig");
  CSCBaseboard::checkConfigParameters(
      nplanes_hit_pattern, max_nplanes_hit_pattern, def_nplanes_hit_pattern, "nplanes_hit_pattern");
  CSCBaseboard::checkConfigParameters(
      pid_thresh_pretrig, max_pid_thresh_pretrig, def_pid_thresh_pretrig, "pid_thresh_pretrig");
  CSCBaseboard::checkConfigParameters(min_separation, max_min_separation, def_min_separation, "min_separation");
  CSCBaseboard::checkConfigParameters(
      tmb_l1a_window_size, max_tmb_l1a_window_size, def_tmb_l1a_window_size, "tmb_l1a_window_size");
}

void CSCCathodeLCTProcessor::clear() {
  thePreTriggerDigis.clear();
  thePreTriggerBXs.clear();
  for (int bx = 0; bx < CSCConstants::MAX_CLCT_TBINS; bx++) {
    bestCLCT[bx].clear();
    secondCLCT[bx].clear();
  }
}

std::vector<CSCCLCTDigi> CSCCathodeLCTProcessor::run(const CSCComparatorDigiCollection* compdc) {
  // This is the version of the run() function that is called when running
  // over the entire detector.  It gets the comparator & timing info from the
  // comparator digis and then passes them on to another run() function.

  // clear(); // redundant; called by L1MuCSCMotherboard.

  static std::atomic<bool> config_dumped{false};
  if ((infoV > 0) && !config_dumped) {
    dumpConfigParams();
    config_dumped = true;
  }

  // Get the number of strips and stagger of layers for the given chamber.
  // Do it only once per chamber.
  if (numStrips == 0) {
    if (cscChamber_) {
      numStrips = cscChamber_->layer(1)->geometry()->numberOfStrips();
      // ME1/a is known to the readout hardware as strips 65-80 of ME1/1.
      // Still need to decide whether we do any special adjustments to
      // reconstruct LCTs in this region (3:1 ganged strips); for now, we
      // simply allow for hits in ME1/a and apply standard reconstruction
      // to them.
      // For SLHC ME1/1 is set to have 4 CFEBs in ME1/b and 3 CFEBs in ME1/a
      if (isME11_) {
        if (theRing == 4) {
          if (infoV >= 0) {
            edm::LogError("L1CSCTPEmulatorSetupError")
                << "+++ Invalid ring number for this processor " << theRing << " was set in the config."
                << " +++\n"
                << "+++ CSC geometry looks garbled; no emulation possible +++\n";
          }
        }
        if (!disableME1a_ && theRing == 1 && !gangedME1a_)
          numStrips = CSCConstants::MAX_NUM_STRIPS_7CFEBS;
        if (!disableME1a_ && theRing == 1 && gangedME1a_)
          numStrips = CSCConstants::MAX_NUM_STRIPS;
        if (disableME1a_ && theRing == 1)
          numStrips = CSCConstants::MAX_NUM_STRIPS_ME1B;
      }

      if (numStrips > CSCConstants::MAX_NUM_STRIPS_7CFEBS) {
        if (infoV >= 0)
          edm::LogError("L1CSCTPEmulatorSetupError")
              << "+++ Number of strips, " << numStrips << " found in "
              << CSCDetId::chamberName(theEndcap, theStation, theRing, theChamber) << " (sector " << theSector
              << " subsector " << theSubsector << " trig id. " << theTrigChamber << ")"
              << " exceeds max expected, " << CSCConstants::MAX_NUM_STRIPS_7CFEBS << " +++\n"
              << "+++ CSC geometry looks garbled; no emulation possible +++\n";
        numStrips = -1;
      }
      // The strips for a given layer may be offset from the adjacent layers.
      // This was done in order to improve resolution.  We need to find the
      // 'staggering' for each layer and make necessary conversions in our
      // arrays.  -JM
      // In the TMB-07 firmware, half-strips in odd layers (layers are
      // counted as ly0-ly5) are shifted by -1 half-strip, whereas in
      // the previous firmware versions half-strips in even layers
      // were shifted by +1 half-strip.  This difference is due to a
      // change from ly3 to ly2 in the choice of the key layer, and
      // the intention to keep half-strips in the key layer unchanged.
      // In the emulator, we use the old way for both cases, to avoid
      // negative half-strip numbers.  This will necessitate a
      // subtraction of 1 half-strip for TMB-07 later on. -SV.
      for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++) {
        stagger[i_layer] = (cscChamber_->layer(i_layer + 1)->geometry()->stagger() + 1) / 2;
      }
    } else {
      if (infoV >= 0)
        edm::LogError("L1CSCTPEmulatorConfigError")
            << " " << CSCDetId::chamberName(theEndcap, theStation, theRing, theChamber) << " (sector " << theSector
            << " subsector " << theSubsector << " trig id. " << theTrigChamber << ")"
            << " is not defined in current geometry! +++\n"
            << "+++ CSC geometry looks garbled; no emulation possible +++\n";
      numStrips = -1;
    }
  }

  if (numStrips < 0) {
    if (infoV >= 0)
      edm::LogError("L1CSCTPEmulatorConfigError")
          << " " << CSCDetId::chamberName(theEndcap, theStation, theRing, theChamber) << " (sector " << theSector
          << " subsector " << theSubsector << " trig id. " << theTrigChamber << "):"
          << " numStrips = " << numStrips << "; CLCT emulation skipped! +++";
    std::vector<CSCCLCTDigi> emptyV;
    return emptyV;
  }

  // Get comparator digis in this chamber.
  bool noDigis = getDigis(compdc);

  if (!noDigis) {
    // Get halfstrip times from comparator digis.
    std::vector<int> halfstrip[CSCConstants::NUM_LAYERS][CSCConstants::NUM_HALF_STRIPS_7CFEBS];
    readComparatorDigis(halfstrip);

    // Pass arrays of halfstrips on to another run() doing the
    // LCT search.
    // If the number of layers containing digis is smaller than that
    // required to trigger, quit right away.  (If LCT-based digi suppression
    // is implemented one day, this condition will have to be changed
    // to the number of planes required to pre-trigger.)
    unsigned int layersHit = 0;
    for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++) {
      for (int i_hstrip = 0; i_hstrip < CSCConstants::NUM_HALF_STRIPS_7CFEBS; i_hstrip++) {
        if (!halfstrip[i_layer][i_hstrip].empty()) {
          layersHit++;
          break;
        }
      }
    }
    // Run the algorithm only if the probability for the pre-trigger
    // to fire is not null.  (Pre-trigger decisions are used for the
    // strip read-out conditions in DigiToRaw.)
    if (layersHit >= nplanes_hit_pretrig)
      run(halfstrip);
  }

  // Return vector of CLCTs.
  std::vector<CSCCLCTDigi> tmpV = getCLCTs();

  // shift the BX from 7 to 8
  // the unpacked real data CLCTs have central BX at bin 7
  // however in simulation the central BX  is bin 8
  // to make a proper comparison with ALCTs we need
  // CLCT and ALCT to have the central BX in the same bin
  // this shift does not affect the readout of the CLCTs
  // emulated CLCTs put in the event should be centered at bin 7 (as in data)
  for (auto& p : tmpV) {
    p.setBX(p.getBX() + alctClctOffset_);
  }

  return tmpV;
}

void CSCCathodeLCTProcessor::run(
    const std::vector<int> halfstrip[CSCConstants::NUM_LAYERS][CSCConstants::NUM_HALF_STRIPS_7CFEBS]) {
  // This version of the run() function can either be called in a standalone
  // test, being passed the halfstrip times, or called by the
  // run() function above.  It uses the findLCTs() method to find vectors
  // of LCT candidates. These candidates are sorted and the best two per bx
  // are returned.
  std::vector<CSCCLCTDigi> CLCTlist = findLCTs(halfstrip);

  // LCT sorting.
  if (CLCTlist.size() > 1)
    sort(CLCTlist.begin(), CLCTlist.end(), std::greater<CSCCLCTDigi>());

  // Take the best two candidates per bx.
  for (const auto& p : CLCTlist) {
    const int bx = p.getBX();
    if (bx >= CSCConstants::MAX_CLCT_TBINS) {
      if (infoV > 0)
        edm::LogWarning("L1CSCTPEmulatorOutOfTimeCLCT")
            << "+++ Bx of CLCT candidate, " << bx << ", exceeds max allowed, " << CSCConstants::MAX_CLCT_TBINS - 1
            << "; skipping it... +++\n";
      continue;
    }

    if (!bestCLCT[bx].isValid()) {
      bestCLCT[bx] = p;
    } else if (!secondCLCT[bx].isValid()) {
      secondCLCT[bx] = p;
    }
  }

  for (int bx = 0; bx < CSCConstants::MAX_CLCT_TBINS; bx++) {
    if (bestCLCT[bx].isValid()) {
      bestCLCT[bx].setTrknmb(1);
      if (infoV > 0)
        LogDebug("CSCCathodeLCTProcessor")
            << bestCLCT[bx] << " found in " << CSCDetId::chamberName(theEndcap, theStation, theRing, theChamber)
            << " (sector " << theSector << " subsector " << theSubsector << " trig id. " << theTrigChamber << ")"
            << "\n";
    }
    if (secondCLCT[bx].isValid()) {
      secondCLCT[bx].setTrknmb(2);
      if (infoV > 0)
        LogDebug("CSCCathodeLCTProcessor")
            << secondCLCT[bx] << " found in " << CSCDetId::chamberName(theEndcap, theStation, theRing, theChamber)
            << " (sector " << theSector << " subsector " << theSubsector << " trig id. " << theTrigChamber << ")"
            << "\n";
    }
  }
  // Now that we have our best CLCTs, they get correlated with the best
  // ALCTs and then get sent to the MotherBoard.  -JM
}

bool CSCCathodeLCTProcessor::getDigis(const CSCComparatorDigiCollection* compdc) {
  bool noDigis = true;

  // Loop over layers and save comparator digis on each one into digiV[layer].
  for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++) {
    digiV[i_layer].clear();

    CSCDetId detid(theEndcap, theStation, theRing, theChamber, i_layer + 1);
    getDigis(compdc, detid);

    if (isME11_ && !disableME1a_) {
      CSCDetId detid_me1a(theEndcap, theStation, 4, theChamber, i_layer + 1);
      getDigis(compdc, detid_me1a);
    }

    if (!digiV[i_layer].empty()) {
      noDigis = false;
      if (infoV > 1) {
        LogTrace("CSCCathodeLCTProcessor") << "found " << digiV[i_layer].size() << " comparator digi(s) in layer "
                                           << i_layer << " of " << detid.chamberName() << " (trig. sector " << theSector
                                           << " subsector " << theSubsector << " id " << theTrigChamber << ")";
      }
    }
  }

  return noDigis;
}

void CSCCathodeLCTProcessor::getDigis(const CSCComparatorDigiCollection* compdc, const CSCDetId& id) {
  const bool me1a = (id.station() == 1) && (id.ring() == 4);
  const CSCComparatorDigiCollection::Range rcompd = compdc->get(id);
  for (CSCComparatorDigiCollection::const_iterator digiIt = rcompd.first; digiIt != rcompd.second; ++digiIt) {
    const unsigned int origStrip = digiIt->getStrip();
    const unsigned int maxStripsME1a =
        gangedME1a_ ? CSCConstants::MAX_NUM_STRIPS_ME1A_GANGED : CSCConstants::MAX_NUM_STRIPS_ME1A_UNGANGED;
    // this special case can only be reached in MC
    // in real data, the comparator digis have always ring==1
    if (me1a && origStrip <= maxStripsME1a && !disableME1a_) {
      // Move ME1/A comparators from CFEB=0 to CFEB=4 if this has not
      // been done already.
      CSCComparatorDigi digi_corr(
          origStrip + CSCConstants::MAX_NUM_STRIPS_ME1B, digiIt->getComparator(), digiIt->getTimeBinWord());
      digiV[id.layer() - 1].push_back(digi_corr);
    } else {
      digiV[id.layer() - 1].push_back(*digiIt);
    }
  }
}

void CSCCathodeLCTProcessor::readComparatorDigis(
    std::vector<int> halfstrip[CSCConstants::NUM_LAYERS][CSCConstants::NUM_HALF_STRIPS_7CFEBS]) {
  for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++) {
    int i_digi = 0;  // digi counter, for dumps.
    for (std::vector<CSCComparatorDigi>::iterator pld = digiV[i_layer].begin(); pld != digiV[i_layer].end();
         pld++, i_digi++) {
      // Dump raw digi info.
      if (infoV > 1) {
        std::ostringstream strstrm;
        strstrm << "Comparator digi: comparator = " << pld->getComparator() << " strip #" << pld->getStrip()
                << " time bins on:";
        std::vector<int> bx_times = pld->getTimeBinsOn();
        for (unsigned int tbin = 0; tbin < bx_times.size(); tbin++)
          strstrm << " " << bx_times[tbin];
        LogTrace("CSCCathodeLCTProcessor") << strstrm.str();
      }

      // Get comparator: 0/1 for left/right halfstrip for each comparator
      // that fired.
      int thisComparator = pld->getComparator();
      if (thisComparator != 0 && thisComparator != 1) {
        if (infoV >= 0)
          edm::LogWarning("L1CSCTPEmulatorWrongInput")
              << "+++ station " << theStation << " ring " << theRing << " chamber " << theChamber
              << " Found comparator digi with wrong comparator value = " << thisComparator << "; skipping it... +++\n";
        continue;
      }

      // Get strip number.
      int thisStrip = pld->getStrip() - 1;  // count from 0
      if (thisStrip < 0 || thisStrip >= numStrips) {
        if (infoV >= 0)
          edm::LogWarning("L1CSCTPEmulatorWrongInput")
              << "+++ station " << theStation << " ring " << theRing << " chamber " << theChamber
              << " Found comparator digi with wrong strip number = " << thisStrip << " (max strips = " << numStrips
              << "); skipping it... +++\n";
        continue;
      }
      // 2*strip: convert strip to 1/2 strip
      // comp   : comparator output
      // stagger: stagger for this layer
      int thisHalfstrip = 2 * thisStrip + thisComparator + stagger[i_layer];
      if (thisHalfstrip >= 2 * numStrips + 1) {
        if (infoV >= 0)
          edm::LogWarning("L1CSCTPEmulatorWrongInput")
              << "+++ station " << theStation << " ring " << theRing << " chamber " << theChamber
              << " Found wrong halfstrip number = " << thisHalfstrip << "; skipping this digi... +++\n";
        continue;
      }

      // Get bx times on this digi and check that they are within the bounds.
      std::vector<int> bx_times = pld->getTimeBinsOn();
      for (unsigned int i = 0; i < bx_times.size(); i++) {
        // Total number of time bins in DAQ readout is given by fifo_tbins,
        // which thus determines the maximum length of time interval.
        //
        // In data, only the CLCT in the time bin that was matched with L1A are read out
        // while comparator digi is read out by 12 time bin, which includes 12 time bin info
        // in other word, CLCTs emulated from comparator digis usually showed the OTMB behavior in 12 time bin
        // while CLCT from data only showed 1 time bin OTMB behavior
        // the CLCT emulated from comparator digis usually is centering at time bin 7 (BX7) and
        // it is definitly safe to ignore any CLCTs in bx 0 or 1 and those CLCTs will never impacts on any triggers
        if (bx_times[i] > 1 && bx_times[i] < static_cast<int>(fifo_tbins)) {
          if (i == 0 || (i > 0 && bx_times[i] - bx_times[i - 1] >= static_cast<int>(hit_persist))) {
            // A later hit on the same strip is ignored during the
            // number of clocks defined by the "hit_persist" parameter
            // (i.e., 6 bx's by default).
            if (infoV > 1)
              LogTrace("CSCCathodeLCTProcessor")
                  << "Comp digi: layer " << i_layer + 1 << " digi #" << i_digi + 1 << " strip " << thisStrip
                  << " halfstrip " << thisHalfstrip << " time " << bx_times[i] << " comparator " << thisComparator
                  << " stagger " << stagger[i_layer];
            halfstrip[i_layer][thisHalfstrip].push_back(bx_times[i]);
          } else if (i > 0) {
            if (infoV > 1)
              LogTrace("CSCCathodeLCTProcessor")
                  << "+++ station " << theStation << " ring " << theRing << " chamber " << theChamber
                  << " Skipping comparator digi: strip = " << thisStrip << ", layer = " << i_layer + 1
                  << ", bx = " << bx_times[i] << ", bx of previous hit = " << bx_times[i - 1];
          }
        } else {
          if (infoV > 1)
            LogTrace("CSCCathodeLCTProcessor") << "+++ station " << theStation << " ring " << theRing << " chamber "
                                               << theChamber << "+++ Skipping comparator digi: strip = " << thisStrip
                                               << ", layer = " << i_layer + 1 << ", bx = " << bx_times[i] << " +++";
        }
      }
    }
  }
}

// TMB-07 version.
std::vector<CSCCLCTDigi> CSCCathodeLCTProcessor::findLCTs(
    const std::vector<int> halfstrip[CSCConstants::NUM_LAYERS][CSCConstants::NUM_HALF_STRIPS_7CFEBS]) {
  std::vector<CSCCLCTDigi> lctList;

  // Max. number of half-strips for this chamber.
  const int maxHalfStrips = 2 * numStrips + 1;

  if (infoV > 1)
    dumpDigis(halfstrip, maxHalfStrips);

  // 2 possible LCTs per CSC x 7 LCT quantities
  int keystrip_data[CSCConstants::MAX_CLCTS_PER_PROCESSOR][CLCT_NUM_QUANTITIES] = {{0}};
  unsigned int pulse[CSCConstants::NUM_LAYERS][CSCConstants::NUM_HALF_STRIPS_7CFEBS];

  // Fire half-strip one-shots for hit_persist bx's (4 bx's by default).
  pulseExtension(halfstrip, maxHalfStrips, pulse);

  unsigned int start_bx = start_bx_shift;
  // Stop drift_delay bx's short of fifo_tbins since at later bx's we will
  // not have a full set of hits to start pattern search anyway.
  unsigned int stop_bx = fifo_tbins - drift_delay;
  // Allow for more than one pass over the hits in the time window.
  while (start_bx < stop_bx) {
    // All half-strip pattern envelopes are evaluated simultaneously, on every
    // clock cycle.
    int first_bx = 999;
    bool pre_trig = preTrigger(pulse, start_bx, first_bx);

    // If any of half-strip envelopes has enough layers hit in it, TMB
    // will pre-trigger.
    if (pre_trig) {
      thePreTriggerBXs.push_back(first_bx);
      if (infoV > 1)
        LogTrace("CSCCathodeLCTProcessor") << "..... pretrigger at bx = " << first_bx << "; waiting drift delay .....";

      // TMB latches LCTs drift_delay clocks after pretrigger.
      int latch_bx = first_bx + drift_delay;
      bool hits_in_time = patternFinding(pulse, maxHalfStrips, latch_bx);
      if (infoV > 1) {
        if (hits_in_time) {
          for (int hstrip = stagger[CSCConstants::KEY_CLCT_LAYER - 1]; hstrip < maxHalfStrips; hstrip++) {
            if (nhits[hstrip] > 0) {
              LogTrace("CSCCathodeLCTProcessor")
                  << " bx = " << std::setw(2) << latch_bx << " --->"
                  << " halfstrip = " << std::setw(3) << hstrip << " best pid = " << std::setw(2) << best_pid[hstrip]
                  << " nhits = " << nhits[hstrip];
            }
          }
        }
      }
      // The pattern finder runs continuously, so another pre-trigger
      // could occur already at the next bx.
      //start_bx = first_bx + 1;

      // Quality for sorting.
      int quality[CSCConstants::NUM_HALF_STRIPS_7CFEBS];
      int best_halfstrip[CSCConstants::MAX_CLCTS_PER_PROCESSOR], best_quality[CSCConstants::MAX_CLCTS_PER_PROCESSOR];
      for (int ilct = 0; ilct < CSCConstants::MAX_CLCTS_PER_PROCESSOR; ilct++) {
        best_halfstrip[ilct] = -1;
        best_quality[ilct] = 0;
      }

      // Calculate quality from pattern id and number of hits, and
      // simultaneously select best-quality LCT.
      if (hits_in_time) {
        for (int hstrip = stagger[CSCConstants::KEY_CLCT_LAYER - 1]; hstrip < maxHalfStrips; hstrip++) {
          // The bend-direction bit pid[0] is ignored (left and right
          // bends have equal quality).
          quality[hstrip] = (best_pid[hstrip] & 14) | (nhits[hstrip] << 5);
          if (quality[hstrip] > best_quality[0]) {
            best_halfstrip[0] = hstrip;
            best_quality[0] = quality[hstrip];
          }
          if (infoV > 1 && quality[hstrip] > 0) {
            LogTrace("CSCCathodeLCTProcessor")
                << " 1st CLCT: halfstrip = " << std::setw(3) << hstrip << " quality = " << std::setw(3)
                << quality[hstrip] << " nhits = " << std::setw(3) << nhits[hstrip] << " pid = " << std::setw(3)
                << best_pid[hstrip] << " best halfstrip = " << std::setw(3) << best_halfstrip[0]
                << " best quality = " << std::setw(3) << best_quality[0];
          }
        }
      }

      // If 1st best CLCT is found, look for the 2nd best.
      if (best_halfstrip[0] >= 0) {
        // Mark keys near best CLCT as busy by setting their quality to
        // zero, and repeat the search.
        markBusyKeys(best_halfstrip[0], best_pid[best_halfstrip[0]], quality);

        for (int hstrip = stagger[CSCConstants::KEY_CLCT_LAYER - 1]; hstrip < maxHalfStrips; hstrip++) {
          if (quality[hstrip] > best_quality[1]) {
            best_halfstrip[1] = hstrip;
            best_quality[1] = quality[hstrip];
          }
          if (infoV > 1 && quality[hstrip] > 0) {
            LogTrace("CSCCathodeLCTProcessor")
                << " 2nd CLCT: halfstrip = " << std::setw(3) << hstrip << " quality = " << std::setw(3)
                << quality[hstrip] << " nhits = " << std::setw(3) << nhits[hstrip] << " pid = " << std::setw(3)
                << best_pid[hstrip] << " best halfstrip = " << std::setw(3) << best_halfstrip[1]
                << " best quality = " << std::setw(3) << best_quality[1];
          }
        }

        // Pattern finder.
        //bool ptn_trig = false;
        for (int ilct = 0; ilct < CSCConstants::MAX_CLCTS_PER_PROCESSOR; ilct++) {
          int best_hs = best_halfstrip[ilct];
          if (best_hs >= 0 && nhits[best_hs] >= nplanes_hit_pattern) {
            //ptn_trig = true;
            keystrip_data[ilct][CLCT_PATTERN] = best_pid[best_hs];
            keystrip_data[ilct][CLCT_BEND] =
                CSCPatternBank::clct_pattern[best_pid[best_hs]][CSCConstants::MAX_HALFSTRIPS_IN_PATTERN];
            // Remove stagger if any.
            keystrip_data[ilct][CLCT_STRIP] = best_hs - stagger[CSCConstants::KEY_CLCT_LAYER - 1];
            keystrip_data[ilct][CLCT_BX] = first_bx;
            keystrip_data[ilct][CLCT_STRIP_TYPE] = 1;  // obsolete
            keystrip_data[ilct][CLCT_QUALITY] = nhits[best_hs];
            keystrip_data[ilct][CLCT_CFEB] = keystrip_data[ilct][CLCT_STRIP] / CSCConstants::NUM_HALF_STRIPS_PER_CFEB;
            int halfstrip_in_cfeb = keystrip_data[ilct][CLCT_STRIP] -
                                    CSCConstants::NUM_HALF_STRIPS_PER_CFEB * keystrip_data[ilct][CLCT_CFEB];

            if (infoV > 1)
              LogTrace("CSCCathodeLCTProcessor")
                  << " Final selection: ilct " << ilct << " key halfstrip " << keystrip_data[ilct][CLCT_STRIP]
                  << " quality " << keystrip_data[ilct][CLCT_QUALITY] << " pattern "
                  << keystrip_data[ilct][CLCT_PATTERN] << " bx " << keystrip_data[ilct][CLCT_BX];

            CSCCLCTDigi thisLCT(1,
                                keystrip_data[ilct][CLCT_QUALITY],
                                keystrip_data[ilct][CLCT_PATTERN],
                                keystrip_data[ilct][CLCT_STRIP_TYPE],
                                keystrip_data[ilct][CLCT_BEND],
                                halfstrip_in_cfeb,
                                keystrip_data[ilct][CLCT_CFEB],
                                keystrip_data[ilct][CLCT_BX]);
            lctList.push_back(thisLCT);
          }
        }
      }  //find CLCT, end of best_halfstrip[0] >= 0

      //if (ptn_trig) {
      // Once there was a trigger, CLCT pre-trigger state machine
      // checks the number of hits that lie on a pattern template
      // at every bx, and waits for it to drop below threshold.
      // The search for CLCTs resumes only when the number of hits
      // drops below threshold.
      start_bx = fifo_tbins;
      // Stop checking drift_delay bx's short of fifo_tbins since
      // at later bx's we won't have a full set of hits for a
      // pattern search anyway.
      unsigned int stop_time = fifo_tbins - drift_delay;
      for (unsigned int bx = latch_bx + 1; bx < stop_time; bx++) {
        bool return_to_idle = true;
        bool hits_in_time = patternFinding(pulse, maxHalfStrips, bx);
        if (hits_in_time) {
          for (int hstrip = stagger[CSCConstants::KEY_CLCT_LAYER - 1]; hstrip < maxHalfStrips; hstrip++) {
            //if (nhits[hstrip] >= nplanes_hit_pattern) {
            if (nhits[hstrip] >= nplanes_hit_pretrig) {  //Tao, move dead time to pretrigger level
              if (infoV > 1)
                LogTrace("CSCCathodeLCTProcessor") << " State machine busy at bx = " << bx;
              return_to_idle = false;
              break;
            }
          }
        }
        if (return_to_idle) {
          if (infoV > 1)
            LogTrace("CSCCathodeLCTProcessor") << " State machine returns to idle state at bx = " << bx;
          start_bx = bx;
          break;
        }
      }
      //}
    }  //pre_trig
    else {
      start_bx = first_bx + 1;  // no dead time
    }
  }

  return lctList;
}  // findLCTs -- TMB-07 version.

// Common to all versions.
void CSCCathodeLCTProcessor::pulseExtension(
    const std::vector<int> time[CSCConstants::NUM_LAYERS][CSCConstants::NUM_HALF_STRIPS_7CFEBS],
    const int nStrips,
    unsigned int pulse[CSCConstants::NUM_LAYERS][CSCConstants::NUM_HALF_STRIPS_7CFEBS]) {
  static const unsigned int bits_in_pulse = 8 * sizeof(pulse[0][0]);

  // Clear pulse array.  This array will be used as a bit representation of
  // hit times.  For example: if strip[1][2] has a value of 3, then 1 shifted
  // left 3 will be bit pattern of pulse[1][2].  This would make the pattern
  // look like 0000000000001000.  Then add on additional bits to signify
  // the duration of a signal (hit_persist, formerly bx_width) to simulate
  // the TMB's drift delay.  So for the same pulse[1][2] with a hit_persist
  // of 3 would look like 0000000000111000.  This is similating the digital
  // one-shot in the TMB.
  for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++)
    for (int i_strip = 0; i_strip < nStrips; i_strip++)
      pulse[i_layer][i_strip] = 0;

  // Loop over all layers and halfstrips.
  for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++) {
    for (int i_strip = 0; i_strip < nStrips; i_strip++) {
      // If there is a hit, simulate digital one-shot persistence starting
      // in the bx of the initial hit.  Fill this into pulse[][].
      if (!time[i_layer][i_strip].empty()) {
        std::vector<int> bx_times = time[i_layer][i_strip];
        for (unsigned int i = 0; i < bx_times.size(); i++) {
          // Check that min and max times are within the allowed range.
          if (bx_times[i] < 0 || bx_times[i] + hit_persist >= bits_in_pulse) {
            if (infoV > 0)
              edm::LogWarning("L1CSCTPEmulatorOutOfTimeDigi")
                  << "+++ BX time of comparator digi (halfstrip = " << i_strip << " layer = " << i_layer
                  << ") bx = " << bx_times[i] << " is not within the range (0-" << bits_in_pulse
                  << "] allowed for pulse extension.  Skip this digi! +++\n";
            continue;
          }
          if (bx_times[i] >= start_bx_shift) {
            for (unsigned int bx = bx_times[i]; bx < bx_times[i] + hit_persist; ++bx)
              pulse[i_layer][i_strip] = pulse[i_layer][i_strip] | (1 << bx);
          }
        }
      }
    }
  }
}  // pulseExtension.

// TMB-07 version.
bool CSCCathodeLCTProcessor::preTrigger(
    const unsigned int pulse[CSCConstants::NUM_LAYERS][CSCConstants::NUM_HALF_STRIPS_7CFEBS],
    const int start_bx,
    int& first_bx) {
  if (infoV > 1)
    LogTrace("CSCCathodeLCTProcessor") << "....................PreTrigger...........................";

  // Max. number of half-strips for this chamber.
  const int nStrips = 2 * numStrips + 1;

  int nPreTriggers = 0;

  bool pre_trig = false;
  // Now do a loop over bx times to see (if/when) track goes over threshold
  for (unsigned int bx_time = start_bx; bx_time < fifo_tbins; bx_time++) {
    // For any given bunch-crossing, start at the lowest keystrip and look for
    // the number of separate layers in the pattern for that keystrip that have
    // pulses at that bunch-crossing time.  Do the same for the next keystrip,
    // etc.  Then do the entire process again for the next bunch-crossing, etc
    // until you find a pre-trigger.
    bool hits_in_time = patternFinding(pulse, nStrips, bx_time);
    if (hits_in_time) {
      for (int hstrip = stagger[CSCConstants::KEY_CLCT_LAYER - 1]; hstrip < nStrips; hstrip++) {
        if (infoV > 1) {
          if (nhits[hstrip] > 0) {
            LogTrace("CSCCathodeLCTProcessor")
                << " bx = " << std::setw(2) << bx_time << " --->"
                << " halfstrip = " << std::setw(3) << hstrip << " best pid = " << std::setw(2) << best_pid[hstrip]
                << " nhits = " << nhits[hstrip];
          }
        }
        ispretrig[hstrip] = false;
        if (nhits[hstrip] >= nplanes_hit_pretrig && best_pid[hstrip] >= pid_thresh_pretrig) {
          pre_trig = true;
          ispretrig[hstrip] = true;

          // write each pre-trigger to output
          nPreTriggers++;
          const int bend = CSCPatternBank::clct_pattern[best_pid[hstrip]][CSCConstants::MAX_HALFSTRIPS_IN_PATTERN];
          const int halfstrip = hstrip % CSCConstants::NUM_HALF_STRIPS_PER_CFEB;
          const int cfeb = hstrip / CSCConstants::NUM_HALF_STRIPS_PER_CFEB;
          thePreTriggerDigis.push_back(CSCCLCTPreTriggerDigi(
              1, nhits[hstrip], best_pid[hstrip], 1, bend, halfstrip, cfeb, bx_time, nPreTriggers, 0));
        }
      }

      if (pre_trig) {
        first_bx = bx_time;  // bx at time of pretrigger
        return true;
      }
    }
  }  // end loop over bx times

  if (infoV > 1)
    LogTrace("CSCCathodeLCTProcessor") << "no pretrigger, returning \n";
  first_bx = fifo_tbins;
  return false;
}  // preTrigger -- TMB-07 version.

// TMB-07 version.
bool CSCCathodeLCTProcessor::patternFinding(
    const unsigned int pulse[CSCConstants::NUM_LAYERS][CSCConstants::NUM_HALF_STRIPS_7CFEBS],
    const int nStrips,
    const unsigned int bx_time) {
  if (bx_time >= fifo_tbins)
    return false;

  // This loop is a quick check of a number of layers hit at bx_time: since
  // most of the time it is 0, this check helps to speed-up the execution
  // substantially.
  unsigned int layers_hit = 0;
  for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++) {
    for (int i_hstrip = 0; i_hstrip < nStrips; i_hstrip++) {
      if (((pulse[i_layer][i_hstrip] >> bx_time) & 1) == 1) {
        layers_hit++;
        break;
      }
    }
  }
  if (layers_hit < nplanes_hit_pretrig)
    return false;

  for (int key_hstrip = 0; key_hstrip < nStrips; key_hstrip++) {
    best_pid[key_hstrip] = 0;
    nhits[key_hstrip] = 0;
    first_bx_corrected[key_hstrip] = -999;
  }

  // Loop over candidate key strips.
  bool hit_layer[CSCConstants::NUM_LAYERS];
  for (int key_hstrip = stagger[CSCConstants::KEY_CLCT_LAYER - 1]; key_hstrip < nStrips; key_hstrip++) {
    // Loop over patterns and look for hits matching each pattern.
    for (unsigned int pid = CSCConstants::NUM_CLCT_PATTERNS - 1; pid >= pid_thresh_pretrig; pid--) {
      layers_hit = 0;
      for (int ilayer = 0; ilayer < CSCConstants::NUM_LAYERS; ilayer++)
        hit_layer[ilayer] = false;

      double num_pattern_hits = 0., times_sum = 0.;
      std::multiset<int> mset_for_median;
      mset_for_median.clear();

      // Loop over halfstrips in trigger pattern mask and calculate the
      // "absolute" halfstrip number for each.
      for (int strip_num = 0; strip_num < CSCConstants::MAX_HALFSTRIPS_IN_PATTERN; strip_num++) {
        int this_layer = CSCPatternBank::clct_pattern[pid][strip_num];
        if (this_layer >= 0 && this_layer < CSCConstants::NUM_LAYERS) {
          int this_strip = CSCPatternBank::clct_pattern_offset[strip_num] + key_hstrip;
          if (this_strip >= 0 && this_strip < nStrips) {
            if (infoV > 3)
              LogTrace("CSCCathodeLCTProcessor")
                  << " In patternFinding: key_strip = " << key_hstrip << " pid = " << pid
                  << " strip_num = " << strip_num << " layer = " << this_layer << " strip = " << this_strip;
            // Determine if "one shot" is high at this bx_time
            if (((pulse[this_layer][this_strip] >> bx_time) & 1) == 1) {
              if (hit_layer[this_layer] == false) {
                hit_layer[this_layer] = true;
                layers_hit++;  // determines number of layers hit
              }

              // find at what bx did pulse on this halsfstrip&layer have started
              // use hit_pesrist constraint on how far back we can go
              int first_bx_layer = bx_time;
              for (unsigned int dbx = 0; dbx < hit_persist; dbx++) {
                if (((pulse[this_layer][this_strip] >> (first_bx_layer - 1)) & 1) == 1)
                  first_bx_layer--;
                else
                  break;
              }
              times_sum += (double)first_bx_layer;
              num_pattern_hits += 1.;
              mset_for_median.insert(first_bx_layer);
              if (infoV > 2)
                LogTrace("CSCCathodeLCTProcessor") << " 1st bx in layer: " << first_bx_layer << " sum bx: " << times_sum
                                                   << " #pat. hits: " << num_pattern_hits;
            }
          }
        }
      }  // end loop over strips in pretrigger pattern

      if (layers_hit > nhits[key_hstrip]) {
        best_pid[key_hstrip] = pid;
        nhits[key_hstrip] = layers_hit;

        // calculate median
        const int sz = mset_for_median.size();
        if (sz > 0) {
          std::multiset<int>::iterator im = mset_for_median.begin();
          if (sz > 1)
            std::advance(im, sz / 2 - 1);
          if (sz == 1)
            first_bx_corrected[key_hstrip] = *im;
          else if ((sz % 2) == 1)
            first_bx_corrected[key_hstrip] = *(++im);
          else
            first_bx_corrected[key_hstrip] = ((*im) + (*(++im))) / 2;

#if defined(EDM_ML_DEBUG)
          //LogTrace only ever prints if EDM_ML_DEBUG is defined
          if (infoV > 1) {
            auto lt = LogTrace("CSCCathodeLCTProcessor")
                      << "bx=" << bx_time << " bx_cor=" << first_bx_corrected[key_hstrip] << "  bxset=";
            for (im = mset_for_median.begin(); im != mset_for_median.end(); im++) {
              lt << " " << *im;
            }
          }
#endif
        }
        // Do not loop over the other (worse) patterns if max. numbers of
        // hits is found.
        if (nhits[key_hstrip] == CSCConstants::NUM_LAYERS)
          break;
      }
    }  // end loop over pid
  }    // end loop over candidate key strips
  return true;
}  // patternFinding -- TMB-07 version.

// TMB-07 version.
void CSCCathodeLCTProcessor::markBusyKeys(const int best_hstrip,
                                          const int best_patid,
                                          int quality[CSCConstants::NUM_HALF_STRIPS_7CFEBS]) {
  int nspan = min_separation;
  int pspan = min_separation;

  for (int hstrip = best_hstrip - nspan; hstrip <= best_hstrip + pspan; hstrip++) {
    if (hstrip >= 0 && hstrip < CSCConstants::NUM_HALF_STRIPS_7CFEBS) {
      quality[hstrip] = 0;
    }
  }
}  // markBusyKeys -- TMB-07 version.

// --------------------------------------------------------------------------
// Auxiliary code.
// --------------------------------------------------------------------------
// Dump of configuration parameters.
void CSCCathodeLCTProcessor::dumpConfigParams() const {
  std::ostringstream strm;
  strm << "\n";
  strm << "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n";
  strm << "+                  CLCT configuration parameters:                  +\n";
  strm << "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n";
  strm << " fifo_tbins   [total number of time bins in DAQ readout] = " << fifo_tbins << "\n";
  strm << " fifo_pretrig [start time of cathode raw hits in DAQ readout] = " << fifo_pretrig << "\n";
  strm << " hit_persist  [duration of signal pulse, in 25 ns bins] = " << hit_persist << "\n";
  strm << " drift_delay  [time after pre-trigger before TMB latches LCTs] = " << drift_delay << "\n";
  strm << " nplanes_hit_pretrig [min. number of layers hit for pre-trigger] = " << nplanes_hit_pretrig << "\n";
  strm << " nplanes_hit_pattern [min. number of layers hit for trigger] = " << nplanes_hit_pattern << "\n";
  strm << " pid_thresh_pretrig [lower threshold on pattern id] = " << pid_thresh_pretrig << "\n";
  strm << " min_separation     [region of busy key strips] = " << min_separation << "\n";
  strm << "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n";
  LogDebug("CSCCathodeLCTProcessor") << strm.str();
}

// Reasonably nice dump of digis on half-strips.
void CSCCathodeLCTProcessor::dumpDigis(
    const std::vector<int> strip[CSCConstants::NUM_LAYERS][CSCConstants::NUM_HALF_STRIPS_7CFEBS],
    const int nStrips) const {
  LogDebug("CSCCathodeLCTProcessor") << CSCDetId::chamberName(theEndcap, theStation, theRing, theChamber)
                                     << " strip type: half-strip,  nStrips " << nStrips;

  std::ostringstream strstrm;
  for (int i_strip = 0; i_strip < nStrips; i_strip++) {
    if (i_strip % 10 == 0) {
      if (i_strip < 100)
        strstrm << i_strip / 10;
      else
        strstrm << (i_strip - 100) / 10;
    } else
      strstrm << " ";
    if ((i_strip + 1) % CSCConstants::NUM_HALF_STRIPS_PER_CFEB == 0)
      strstrm << " ";
  }
  strstrm << "\n";
  for (int i_strip = 0; i_strip < nStrips; i_strip++) {
    strstrm << i_strip % 10;
    if ((i_strip + 1) % CSCConstants::NUM_HALF_STRIPS_PER_CFEB == 0)
      strstrm << " ";
  }
  for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++) {
    strstrm << "\n";
    for (int i_strip = 0; i_strip < nStrips; i_strip++) {
      if (!strip[i_layer][i_strip].empty()) {
        std::vector<int> bx_times = strip[i_layer][i_strip];
        // Dump only the first in time.
        strstrm << std::hex << bx_times[0] << std::dec;
      } else {
        strstrm << "-";
      }
      if ((i_strip + 1) % CSCConstants::NUM_HALF_STRIPS_PER_CFEB == 0)
        strstrm << " ";
    }
  }
  LogTrace("CSCCathodeLCTProcessor") << strstrm.str();
}

// Returns vector of read-out CLCTs, if any.  Starts with the vector
// of all found CLCTs and selects the ones in the read-out time window.
std::vector<CSCCLCTDigi> CSCCathodeLCTProcessor::readoutCLCTs() const {
  std::vector<CSCCLCTDigi> tmpV;

  // The start time of the L1A*CLCT coincidence window should be
  // related to the fifo_pretrig parameter, but I am not completely
  // sure how.  For now, just choose it such that the window is
  // centered at bx=7.  This may need further tweaking if the value of
  // tmb_l1a_window_size changes.

  // The number of CLCT bins in the read-out is given by the
  // tmb_l1a_window_size parameter, but made even by setting the LSB
  // of tmb_l1a_window_size to 0.
  //
  static std::atomic<int> lct_bins;
  lct_bins = (tmb_l1a_window_size % 2 == 0) ? tmb_l1a_window_size : tmb_l1a_window_size - 1;
  static std::atomic<int> late_tbins;
  late_tbins = early_tbins + lct_bins;

  static std::atomic<int> ifois{0};
  if (ifois == 0) {
    if (infoV >= 0 && early_tbins < 0) {
      edm::LogWarning("L1CSCTPEmulatorSuspiciousParameters")
          << "+++ early_tbins = " << early_tbins << "; in-time CLCTs are not getting read-out!!! +++"
          << "\n";
    }

    if (late_tbins > CSCConstants::MAX_CLCT_TBINS - 1) {
      if (infoV >= 0)
        edm::LogWarning("L1CSCTPEmulatorSuspiciousParameters")
            << "+++ Allowed range of time bins, [0-" << late_tbins << "] exceeds max allowed, "
            << CSCConstants::MAX_CLCT_TBINS - 1 << " +++\n"
            << "+++ Set late_tbins to max allowed +++\n";
      late_tbins = CSCConstants::MAX_CLCT_TBINS - 1;
    }
    ifois = 1;
  }

  // Start from the vector of all found CLCTs and select those within
  // the CLCT*L1A coincidence window.
  int bx_readout = -1;
  const std::vector<CSCCLCTDigi>& all_lcts = getCLCTs();
  for (const auto& p : all_lcts) {
    if (!p.isValid())
      continue;

    const int bx = p.getBX();
    // Skip CLCTs found too early relative to L1Accept.
    if (bx <= early_tbins) {
      if (infoV > 1)
        LogDebug("CSCCathodeLCTProcessor")
            << " Do not report CLCT on key halfstrip " << p.getKeyStrip() << ": found at bx " << bx
            << ", whereas the earliest allowed bx is " << early_tbins + 1;
      continue;
    }

    // Skip CLCTs found too late relative to L1Accept.
    if (bx > late_tbins) {
      if (infoV > 1)
        LogDebug("CSCCathodeLCTProcessor")
            << " Do not report CLCT on key halfstrip " << p.getKeyStrip() << ": found at bx " << bx
            << ", whereas the latest allowed bx is " << late_tbins;
      continue;
    }

    // If (readout_earliest_2) take only CLCTs in the earliest bx in the read-out window:
    // in digi->raw step, LCTs have to be packed into the TMB header, and
    // currently there is room just for two.
    if (readout_earliest_2) {
      if (bx_readout == -1 || bx == bx_readout) {
        tmpV.push_back(p);
        if (bx_readout == -1)
          bx_readout = bx;
      }
    } else
      tmpV.push_back(p);
  }
  return tmpV;
}

// Returns vector of read-out CLCTs, if any.  Starts with the vector
// of all found CLCTs and selects the ones in the read-out time window.
std::vector<CSCCLCTDigi> CSCCathodeLCTProcessor::readoutCLCTsME1a() const {
  std::vector<CSCCLCTDigi> tmpV;
  if (not(theStation == 1 and (theRing == 1 or theRing == 4)))
    return tmpV;
  const std::vector<CSCCLCTDigi>& allCLCTs = readoutCLCTs();
  for (const auto& clct : allCLCTs)
    if (clct.getCFEB() >= 4)
      tmpV.push_back(clct);
  return tmpV;
}

// Returns vector of read-out CLCTs, if any.  Starts with the vector
// of all found CLCTs and selects the ones in the read-out time window.
std::vector<CSCCLCTDigi> CSCCathodeLCTProcessor::readoutCLCTsME1b() const {
  std::vector<CSCCLCTDigi> tmpV;
  if (not(theStation == 1 and (theRing == 1 or theRing == 4)))
    return tmpV;
  const std::vector<CSCCLCTDigi>& allCLCTs = readoutCLCTs();
  for (const auto& clct : allCLCTs)
    if (clct.getCFEB() < 4)
      tmpV.push_back(clct);
  return tmpV;
}

std::vector<CSCCLCTPreTriggerDigi> CSCCathodeLCTProcessor::preTriggerDigisME1a() const {
  std::vector<CSCCLCTPreTriggerDigi> tmpV;
  if (not(theStation == 1 and (theRing == 1 or theRing == 4)))
    return tmpV;
  const std::vector<CSCCLCTPreTriggerDigi>& allPretriggerdigis = preTriggerDigis();
  for (const auto& preclct : allPretriggerdigis)
    if (preclct.getCFEB() >= 4)
      tmpV.push_back(preclct);
  return tmpV;
}

std::vector<CSCCLCTPreTriggerDigi> CSCCathodeLCTProcessor::preTriggerDigisME1b() const {
  std::vector<CSCCLCTPreTriggerDigi> tmpV;
  if (not(theStation == 1 and (theRing == 1 or theRing == 4)))
    return tmpV;
  const std::vector<CSCCLCTPreTriggerDigi>& allPretriggerdigis = preTriggerDigis();
  for (const auto& preclct : allPretriggerdigis)
    if (preclct.getCFEB() < 4)
      tmpV.push_back(preclct);
  return tmpV;
}

// Returns vector of all found CLCTs, if any.  Used for ALCT-CLCT matching.
std::vector<CSCCLCTDigi> CSCCathodeLCTProcessor::getCLCTs() const {
  std::vector<CSCCLCTDigi> tmpV;
  for (int bx = 0; bx < CSCConstants::MAX_CLCT_TBINS; bx++) {
    if (bestCLCT[bx].isValid())
      tmpV.push_back(bestCLCT[bx]);
    if (secondCLCT[bx].isValid())
      tmpV.push_back(secondCLCT[bx]);
  }
  return tmpV;
}

// shift the BX from 7 to 8
// the unpacked real data CLCTs have central BX at bin 7
// however in simulation the central BX  is bin 8
// to make a proper comparison with ALCTs we need
// CLCT and ALCT to have the central BX in the same bin
CSCCLCTDigi CSCCathodeLCTProcessor::getBestCLCT(int bx) const {
  CSCCLCTDigi lct = bestCLCT[bx];
  lct.setBX(lct.getBX() + alctClctOffset_);
  return lct;
}

CSCCLCTDigi CSCCathodeLCTProcessor::getSecondCLCT(int bx) const {
  CSCCLCTDigi lct = secondCLCT[bx];
  lct.setBX(lct.getBX() + alctClctOffset_);
  return lct;
}