CSCAnodeLCTProcessor.cc

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//-----------------------------------------------------------------------------
//
//   Class: CSCAnodeLCTProcessor
//
//   Description: 
//     This is the simulation for the Anode LCT Processor for the Level-1
//     Trigger.  This processor consists of several stages:
//
//       1. Pulse extension of signals coming from wires.
//       2. Pretrigger for each key-wire.
//       3. Pattern detector if a pretrigger is found for the given key-wire.
//       4. Ghost Cancellation Logic (GCL).
//       5. Best track search and promotion.
//       6. Second best track search and promotion.
//
//     The inputs to the ALCT Processor are wire digis.
//     The output is up to two ALCT digi words.
//
//   Author List: Benn Tannenbaum (1999), Jason Mumford (2002), Slava Valuev.
//                Porting from ORCA by S. Valuev (Slava.Valuev@cern.ch),
//                May 2006.
//
//
//   Modifications: 
//
//-----------------------------------------------------------------------------

#include <L1Trigger/CSCTriggerPrimitives/src/CSCAnodeLCTProcessor.h>
#include <L1Trigger/CSCCommonTrigger/interface/CSCTriggerGeometry.h>
#include <DataFormats/MuonDetId/interface/CSCTriggerNumbering.h>

#include <FWCore/MessageLogger/interface/MessageLogger.h>

#include <set>

//-----------------
// Static variables
//-----------------

/* This is the pattern envelope, which is used to define the collision
   patterns A and B.
   pattern_envelope[0][i]=layer;
   pattern_envelope[1+MEposition][i]=key_wire offset. */
const int CSCAnodeLCTProcessor::pattern_envelope[CSCConstants::NUM_ALCT_PATTERNS][NUM_PATTERN_WIRES] = {
  //Layer
  { 0,  0,  0,
        1,  1,
            2,
            3,  3,
            4,  4,  4,
            5,  5,  5},

  //Keywire offset for ME1 and ME2
  {-2, -1,  0,
       -1,  0,
            0,
            0,  1,
            0,  1,  2,
            0,  1,  2},

  //Keywire offset for ME3 and ME4
  {2,  1,  0,
       1,  0,
           0,
           0, -1,
           0, -1, -2,
           0, -1, -2}
};

// time averaging weights for pattern (used for SLHC version)
const int CSCAnodeLCTProcessor::time_weights[NUM_PATTERN_WIRES] =
  //Layer
  { 0,  1,  1,
        1,  2,
            2,
            2,  1,
            2,  1,  0,
            1,  1,  0};


// These mask the pattern envelope to give the desired accelerator pattern
// and collision patterns A and B.  These masks were meant to be the default
// ones in early 200X, but were never implemented because of limited FPGA
// resources.
const int CSCAnodeLCTProcessor::pattern_mask_slim[CSCConstants::NUM_ALCT_PATTERNS][NUM_PATTERN_WIRES] = {
  // Accelerator pattern
  {0,  0,  1,
       0,  1,
           1,
           1,  0,
           1,  0,  0,
           1,  0,  0},

  // Collision pattern A
  {0,  1,  0,
       1,  1,
           1,
           1,  0,
           0,  1,  0,
           0,  1,  0},

  // Collision pattern B
  {1,  1,  0,
       1,  1,
           1,
           1,  1,
           0,  1,  1,
           0,  0,  1}
};

// Since the test beams in 2003, both collision patterns are "completely
// open".  This is our current default.
const int CSCAnodeLCTProcessor::pattern_mask_open[CSCConstants::NUM_ALCT_PATTERNS][NUM_PATTERN_WIRES] = {
  // Accelerator pattern
  {0,  0,  1,
       0,  1,
           1,
           1,  0,
           1,  0,  0,
           1,  0,  0},

  // Collision pattern A
  {1,  1,  1,
       1,  1,
           1,
           1,  1,
           1,  1,  1,
           1,  1,  1},

  // Collision pattern B
  {1,  1,  1,
       1,  1,
           1,
           1,  1,
           1,  1,  1,
           1,  1,  1}
};

// Special option for narrow pattern for ring 1 stations
const int CSCAnodeLCTProcessor::pattern_mask_r1[CSCConstants::NUM_ALCT_PATTERNS][NUM_PATTERN_WIRES] = {
  // Accelerator pattern
  {0,  0,  1,
       0,  1,
           1,
           1,  0,
           1,  0,  0,
           1,  0,  0},

  // Collision pattern A
  {0,  1,  1,
       1,  1,
           1,
           1,  0,
           1,  1,  0,
           1,  1,  0},

  // Collision pattern B
  {0,  1,  1,
       1,  1,
           1,
           1,  0,
           1,  1,  0,
           1,  1,  0}
};



// Default values of configuration parameters.
const unsigned int CSCAnodeLCTProcessor::def_fifo_tbins   = 16;
const unsigned int CSCAnodeLCTProcessor::def_fifo_pretrig = 10;
const unsigned int CSCAnodeLCTProcessor::def_drift_delay  =  2;
const unsigned int CSCAnodeLCTProcessor::def_nplanes_hit_pretrig =  2;
const unsigned int CSCAnodeLCTProcessor::def_nplanes_hit_pattern =  4;
const unsigned int CSCAnodeLCTProcessor::def_nplanes_hit_accel_pretrig =  2;
const unsigned int CSCAnodeLCTProcessor::def_nplanes_hit_accel_pattern =  4;
const unsigned int CSCAnodeLCTProcessor::def_trig_mode        =  2;  // 3?
const unsigned int CSCAnodeLCTProcessor::def_accel_mode       =  0;  // 1?
const unsigned int CSCAnodeLCTProcessor::def_l1a_window_width =  7;  // 5?

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

CSCAnodeLCTProcessor::CSCAnodeLCTProcessor(unsigned endcap, unsigned station,
                                           unsigned sector, unsigned subsector,
                                           unsigned chamber,
                                           const edm::ParameterSet& conf,
                                           const edm::ParameterSet& comm) : 
                     theEndcap(endcap), theStation(station), theSector(sector),
                     theSubsector(subsector), theTrigChamber(chamber) {
  static bool config_dumped = false;

  // ALCT configuration parameters.
  fifo_tbins   = conf.getParameter<unsigned int>("alctFifoTbins");
  fifo_pretrig = conf.getParameter<unsigned int>("alctFifoPretrig");
  drift_delay  = conf.getParameter<unsigned int>("alctDriftDelay");
  nplanes_hit_pretrig =
    conf.getParameter<unsigned int>("alctNplanesHitPretrig");
  nplanes_hit_pattern =
    conf.getParameter<unsigned int>("alctNplanesHitPattern");
  nplanes_hit_accel_pretrig =
    conf.getParameter<unsigned int>("alctNplanesHitAccelPretrig");
  nplanes_hit_accel_pattern =
    conf.getParameter<unsigned int>("alctNplanesHitAccelPattern");
  trig_mode        = conf.getParameter<unsigned int>("alctTrigMode");
  accel_mode       = conf.getParameter<unsigned int>("alctAccelMode");
  l1a_window_width = conf.getParameter<unsigned int>("alctL1aWindowWidth");

  hit_persist  = conf.getParameter<unsigned int>("alctHitPersist");

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

  // Other parameters.
  // Use open pattern instead of more restrictive (slim) ones.
  isMTCC       = comm.getParameter<bool>("isMTCC");
  // Use TMB07 flag for DAQ-2006 firmware version (implemented in late 2007).
  isTMB07      = comm.getParameter<bool>("isTMB07");

  // Flag for SLHC studies
  isSLHC       = comm.getParameter<bool>("isSLHC");

  // special configuration parameters for ME11 treatment
  disableME1a = comm.getParameter<bool>("disableME1a");

  // separate handle for early time bins
  early_tbins = conf.getParameter<int>("alctEarlyTbins");
  int fpga_latency = 6;
  if (early_tbins<0) early_tbins  = fifo_pretrig - fpga_latency;

  // delta BX time depth for ghostCancellationLogic
  ghost_cancellation_bx_depth = conf.getParameter<int>("alctGhostCancellationBxDepth");

  // whether to consider ALCT candidates' qualities while doing ghostCancellationLogic on +-1 wire groups
  ghost_cancellation_side_quality = conf.getParameter<bool>("alctGhostCancellationSideQuality");

  // deadtime clocks after pretrigger (extra in addition to drift_delay)
  pretrig_extra_deadtime = conf.getParameter<unsigned int>("alctPretrigDeadtime");

  // whether to use narrow pattern mask for the rings close to the beam
  narrow_mask_r1 = conf.getParameter<bool>("alctNarrowMaskForR1");

  // Check and print configuration parameters.
  checkConfigParameters();
  if ((infoV > 0 || isSLHC) && !config_dumped) {
    //std::cout<<"**** ALCT constructor parameters dump ****"<<std::endl;
    dumpConfigParams();
    config_dumped = true;
  }

  numWireGroups = 0;  // Will be set later.
  MESelection   = (theStation < 3) ? 0 : 1;

  theRing = CSCTriggerNumbering::ringFromTriggerLabels(theStation, theTrigChamber);

  theChamber = CSCTriggerNumbering::chamberFromTriggerLabels(theSector, theSubsector,
                                                             theStation, theTrigChamber);

  // trigger numbering doesn't distinguish between ME1a and ME1b chambers:
  isME11 = (theStation == 1 && theRing == 1);

  // whether to calculate bx as corrected_bx instead of pretrigger one
  use_corrected_bx = false;
  if (isSLHC && isME11) {
    use_corrected_bx = conf.getParameter<bool>("alctUseCorrectedBx");
  }

  // run the ALCT processor for the Phase-II ME2/1 integrated local trigger
  runME21ILT_ = conf.existsAs<bool>("runME21ILT")?
    conf.getParameter<bool>("runME21ILT"):false;

  // run the ALCT processor for the Phase-II ME3/1-ME4/1 integrated local trigger
  runME3141ILT_ = conf.existsAs<bool>("runME3141ILT")?
    conf.getParameter<bool>("runME3141ILT"):false;

  //if (theStation==1 && theRing==2) infoV = 3;

  // Load appropriate pattern mask.
  loadPatternMask();
}

CSCAnodeLCTProcessor::CSCAnodeLCTProcessor() :
                       theEndcap(1), theStation(1), theSector(1),
                     theSubsector(1), theTrigChamber(1) {
  // Used for debugging. -JM
  static bool config_dumped = false;

  // ALCT parameters.
  setDefaultConfigParameters();
  infoV = 2;
  isMTCC  = false;
  isTMB07 = true;

  isSLHC = false;
  disableME1a = false;

  early_tbins = 4;

  // Check and print configuration parameters.
  checkConfigParameters();
  if (!config_dumped) {
    //std::cout<<"**** ALCT default constructor parameters dump ****"<<std::endl;
    dumpConfigParams();
    config_dumped = true;
  }

  numWireGroups = CSCConstants::MAX_NUM_WIRES;
  MESelection   = (theStation < 3) ? 0 : 1;

  theRing = CSCTriggerNumbering::ringFromTriggerLabels(theStation, theTrigChamber);
  theChamber = CSCTriggerNumbering::chamberFromTriggerLabels(theSector, theSubsector,
                                                             theStation, theTrigChamber);
  isME11 = (theStation == 1 && theRing == 1);

  // Load pattern mask.
  loadPatternMask();
}


void CSCAnodeLCTProcessor::loadPatternMask() {
  // Load appropriate pattern mask.
  for (int i_patt = 0; i_patt < CSCConstants::NUM_ALCT_PATTERNS; i_patt++) {
    for (int i_wire = 0; i_wire < NUM_PATTERN_WIRES; i_wire++) {
      if (isMTCC || isTMB07) {
        pattern_mask[i_patt][i_wire] = pattern_mask_open[i_patt][i_wire];
        if (narrow_mask_r1 && (theRing == 1 || theRing == 4))
          pattern_mask[i_patt][i_wire] = pattern_mask_r1[i_patt][i_wire];
      }
      else {
        pattern_mask[i_patt][i_wire] = pattern_mask_slim[i_patt][i_wire];
      }
    }
  }
}


void CSCAnodeLCTProcessor::setDefaultConfigParameters() {
  // Set default values for configuration parameters.
  fifo_tbins   = def_fifo_tbins;
  fifo_pretrig = def_fifo_pretrig;
  drift_delay  = def_drift_delay;
  nplanes_hit_pretrig = def_nplanes_hit_pretrig;
  nplanes_hit_pattern = def_nplanes_hit_pattern;
  nplanes_hit_accel_pretrig = def_nplanes_hit_accel_pretrig;
  nplanes_hit_accel_pattern = def_nplanes_hit_accel_pattern;
  trig_mode        = def_trig_mode;
  accel_mode       = def_accel_mode;
  l1a_window_width = def_l1a_window_width;
}

// Set configuration parameters obtained via EventSetup mechanism.
void CSCAnodeLCTProcessor::setConfigParameters(const CSCDBL1TPParameters* conf) {
  static bool config_dumped = false;

  fifo_tbins   = conf->alctFifoTbins();
  fifo_pretrig = conf->alctFifoPretrig();
  drift_delay  = conf->alctDriftDelay();
  nplanes_hit_pretrig = conf->alctNplanesHitPretrig();
  nplanes_hit_pattern = conf->alctNplanesHitPattern();
  nplanes_hit_accel_pretrig = conf->alctNplanesHitAccelPretrig();
  nplanes_hit_accel_pattern = conf->alctNplanesHitAccelPattern();
  trig_mode        = conf->alctTrigMode();
  accel_mode       = conf->alctAccelMode();
  l1a_window_width = conf->alctL1aWindowWidth();

  // Check and print configuration parameters.
  checkConfigParameters();
  if (!config_dumped) {
    //std::cout<<"**** ALCT setConfigParam parameters dump ****"<<std::endl;
    dumpConfigParams();
    config_dumped = true;
  }
}

void CSCAnodeLCTProcessor::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_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_nplanes_hit_accel_pretrig = 1 << 3;
  static const unsigned int max_nplanes_hit_accel_pattern = 1 << 3;
  static const unsigned int max_trig_mode        = 1 << 2;
  static const unsigned int max_accel_mode       = 1 << 2;
  static const unsigned int max_l1a_window_width = MAX_ALCT_BINS; // 4 bits

  // Checks.
  if (fifo_tbins >= max_fifo_tbins) {
    if (infoV >= 0) edm::LogError("L1CSCTPEmulatorConfigError")
      << "+++ Value of fifo_tbins, " << fifo_tbins
      << ", exceeds max allowed, " << max_fifo_tbins-1 << " +++\n"
      << "+++ Try to proceed with the default value, fifo_tbins="
      << def_fifo_tbins << " +++\n";
    fifo_tbins = def_fifo_tbins;
  }
  if (fifo_pretrig >= max_fifo_pretrig) {
    if (infoV >= 0) edm::LogError("L1CSCTPEmulatorConfigError")
      << "+++ Value of fifo_pretrig, " << fifo_pretrig
      << ", exceeds max allowed, " << max_fifo_pretrig-1 << " +++\n"
      << "+++ Try to proceed with the default value, fifo_pretrig="
      << def_fifo_pretrig << " +++\n";
    fifo_pretrig = def_fifo_pretrig;
  }
  if (drift_delay >= max_drift_delay) {
    if (infoV >= 0) edm::LogError("L1CSCTPEmulatorConfigError")
      << "+++ Value of drift_delay, " << drift_delay
      << ", exceeds max allowed, " << max_drift_delay-1 << " +++\n"
      << "+++ Try to proceed with the default value, drift_delay="
      << def_drift_delay << " +++\n";
    drift_delay = def_drift_delay;
  }
  if (nplanes_hit_pretrig >= max_nplanes_hit_pretrig) {
    if (infoV >= 0) edm::LogError("L1CSCTPEmulatorConfigError")
      << "+++ Value of nplanes_hit_pretrig, " << nplanes_hit_pretrig
      << ", exceeds max allowed, " << max_nplanes_hit_pretrig-1 << " +++\n"
      << "+++ Try to proceed with the default value, nplanes_hit_pretrig="
      << nplanes_hit_pretrig << " +++\n";
    nplanes_hit_pretrig = def_nplanes_hit_pretrig;
  }
  if (nplanes_hit_pattern >= max_nplanes_hit_pattern) {
    if (infoV >= 0) edm::LogError("L1CSCTPEmulatorConfigError")
      << "+++ Value of nplanes_hit_pattern, " << nplanes_hit_pattern
      << ", exceeds max allowed, " << max_nplanes_hit_pattern-1 << " +++\n"
      << "+++ Try to proceed with the default value, nplanes_hit_pattern="
      << nplanes_hit_pattern << " +++\n";
    nplanes_hit_pattern = def_nplanes_hit_pattern;
  }
  if (nplanes_hit_accel_pretrig >= max_nplanes_hit_accel_pretrig) {
    if (infoV >= 0) edm::LogError("L1CSCTPEmulatorConfigError")
      << "+++ Value of nplanes_hit_accel_pretrig, "
      << nplanes_hit_accel_pretrig << ", exceeds max allowed, "
      << max_nplanes_hit_accel_pretrig-1 << " +++\n"
      << "+++ Try to proceed with the default value, "
      << "nplanes_hit_accel_pretrig=" << nplanes_hit_accel_pretrig << " +++\n";
    nplanes_hit_accel_pretrig = def_nplanes_hit_accel_pretrig;
  }
  if (nplanes_hit_accel_pattern >= max_nplanes_hit_accel_pattern) {
    if (infoV >= 0) edm::LogError("L1CSCTPEmulatorConfigError")
      << "+++ Value of nplanes_hit_accel_pattern, "
      << nplanes_hit_accel_pattern << ", exceeds max allowed, "
      << max_nplanes_hit_accel_pattern-1 << " +++\n"
      << "+++ Try to proceed with the default value, "
      << "nplanes_hit_accel_pattern=" << nplanes_hit_accel_pattern << " +++\n";
    nplanes_hit_accel_pattern = def_nplanes_hit_accel_pattern;
  }
  if (trig_mode >= max_trig_mode) {
    if (infoV >= 0) edm::LogError("L1CSCTPEmulatorConfigError")
      << "+++ Value of trig_mode, " << trig_mode
      << ", exceeds max allowed, " << max_trig_mode-1 << " +++\n"
      << "+++ Try to proceed with the default value, trig_mode="
      << trig_mode << " +++\n";
    trig_mode = def_trig_mode;
  }
  if (accel_mode >= max_accel_mode) {
    if (infoV >= 0) edm::LogError("L1CSCTPEmulatorConfigError")
      << "+++ Value of accel_mode, " << accel_mode
      << ", exceeds max allowed, " << max_accel_mode-1 << " +++\n"
      << "+++ Try to proceed with the default value, accel_mode="
      << accel_mode << " +++\n";
    accel_mode = def_accel_mode;
  }
  if (l1a_window_width >= max_l1a_window_width) {
    if (infoV >= 0) edm::LogError("L1CSCTPEmulatorConfigError")
      << "+++ Value of l1a_window_width, " << l1a_window_width
      << ", exceeds max allowed, " << max_l1a_window_width-1 << " +++\n"
      << "+++ Try to proceed with the default value, l1a_window_width="
      << l1a_window_width << " +++\n";
    l1a_window_width = def_l1a_window_width;
  }
}

void CSCAnodeLCTProcessor::clear() {
  for (int bx = 0; bx < MAX_ALCT_BINS; bx++) {
    bestALCT[bx].clear();
    secondALCT[bx].clear();
  }
}

void CSCAnodeLCTProcessor::clear(const int wire, const int pattern) {
  /* Clear the data off of selected pattern */
  if (pattern == 0) quality[wire][0] = -999;
  else {
    quality[wire][1] = -999;
    quality[wire][2] = -999;
  }
}

std::vector<CSCALCTDigi>
CSCAnodeLCTProcessor::run(const CSCWireDigiCollection* wiredc) {
  // This is the main routine for normal running.  It gets wire times
  // from the wire digis and then passes them on to another run() function.

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

  static bool config_dumped = false;
  if ((infoV > 0 || isSLHC) && !config_dumped) {
    //std::cout<<"**** ALCT run parameters dump ****"<<std::endl;
    dumpConfigParams();
    config_dumped = true;
  }


  // Get the number of wire groups for the given chamber.  Do it only once
  // per chamber.
  if (numWireGroups == 0) {
    CSCTriggerGeomManager* theGeom = CSCTriggerGeometry::get();
    CSCChamber* chamber = theGeom->chamber(theEndcap, theStation, theSector,
                                           theSubsector, theTrigChamber);
    if (chamber) {
      numWireGroups = chamber->layer(1)->geometry()->numberOfWireGroups();
      if (numWireGroups > CSCConstants::MAX_NUM_WIRES) {
        if (infoV >= 0) edm::LogError("L1CSCTPEmulatorSetupError")
          << "+++ Number of wire groups, " << numWireGroups
          << " found in ME" << ((theEndcap == 1) ? "+" : "-")
          << theStation << "/" << theRing << "/" << theChamber
          << " (sector " << theSector << " subsector " << theSubsector
          << " trig id. " << theTrigChamber << ")"
          << " exceeds max expected, " << CSCConstants::MAX_NUM_WIRES
          << " +++\n" 
          << "+++ CSC geometry looks garbled; no emulation possible +++\n";
        numWireGroups = -1;
      }
    }
    else {
      if (infoV >= 0) edm::LogError("L1CSCTPEmulatorSetupError")
        << "+++ ME" << ((theEndcap == 1) ? "+" : "-")
        << 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";
      numWireGroups = -1;
    }
  }

  if (numWireGroups < 0) {
    if (infoV >= 0) edm::LogError("L1CSCTPEmulatorSetupError")
      << "+++ ME" << ((theEndcap == 1) ? "+" : "-")
      << theStation << "/" << theRing << "/" << theChamber
      << " (sector " << theSector << " subsector " << theSubsector
      << " trig id. " << theTrigChamber << "):"
      << " numWireGroups = " << numWireGroups
      << "; ALCT emulation skipped! +++";
    std::vector<CSCALCTDigi> emptyV;
    return emptyV;
  }

  // Get wire digis in this chamber from wire digi collection.
  bool noDigis = getDigis(wiredc);

  if (!noDigis) {
    // First get wire times from the wire digis.
    std::vector<int>
      wire[CSCConstants::NUM_LAYERS][CSCConstants::MAX_NUM_WIRES];
    readWireDigis(wire);

    // Pass an array of wire times 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.
    const unsigned int min_layers =
      (nplanes_hit_accel_pattern == 0) ? 
        nplanes_hit_pattern :
        ((nplanes_hit_pattern <= nplanes_hit_accel_pattern) ?
           nplanes_hit_pattern :
           nplanes_hit_accel_pattern
        );

    unsigned int layersHit = 0;
    for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++) {
      for (int i_wire = 0; i_wire < numWireGroups; i_wire++) {
        if (!wire[i_layer][i_wire].empty()) {layersHit++; break;}
      }
    }
    if (layersHit >= min_layers) run(wire);
  }

  // Return vector of all found ALCTs.
  std::vector<CSCALCTDigi> tmpV = getALCTs();
  return tmpV;
}

void CSCAnodeLCTProcessor::run(const std::vector<int> wire[CSCConstants::NUM_LAYERS][CSCConstants::MAX_NUM_WIRES]) {
  // This version of the run() function can either be called in a standalone
  // test, being passed the time array, or called by the run() function above.
  // It gets wire times from an input array and then loops over the keywires.
  // All found LCT candidates are sorted and the best two are retained.

  bool trigger = false;

  // Check if there are any in-time hits and do the pulse extension.
  bool chamber_empty = pulseExtension(wire);

  // Only do the rest of the processing if chamber is not empty.
  // 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;
  if (!chamber_empty) {
    for (int i_wire = 0; i_wire < numWireGroups; i_wire++) {
      unsigned int start_bx = 0;
      // Allow for more than one pass over the hits in the time window.
      while (start_bx < stop_bx) {
        if (preTrigger(i_wire, start_bx)) {
          if (infoV > 2) showPatterns(i_wire);
          if (patternDetection(i_wire)) {
            trigger = true;
            break;
          }
          else {
            // Assume that the earliest time when another pre-trigger can
            // occur in case pattern detection failed is bx_pretrigger+4:
            // this seems to match the data.
            start_bx = first_bx[i_wire] + drift_delay + pretrig_extra_deadtime;
          }
        }
        else {
          break;
        }
      }
    }
  }

  // Do the rest only if there is at least one trigger candidate.
  if (trigger) {
    if (isSLHC) ghostCancellationLogicSLHC();
    else ghostCancellationLogic();
    lctSearch();
  }
}

bool CSCAnodeLCTProcessor::getDigis(const CSCWireDigiCollection* wiredc) {
  // Routine for getting digis and filling digiV vector.
  bool noDigis = true;

  // Loop over layers and save wire 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(wiredc, detid);

    // If this is ME1/1, fetch digis in corresponding ME1/A (ring=4) as well.
    if (isME11 && !disableME1a) {
      CSCDetId detid_me1a(theEndcap, theStation, 4, theChamber, i_layer+1);
      getDigis(wiredc, detid_me1a);
    }

    if (!digiV[i_layer].empty()) {
      noDigis = false;
      if (infoV > 1) {
        LogTrace("CSCAnodeLCTProcessor")
          << "found " << digiV[i_layer].size()
          << " wire digi(s) in layer " << i_layer << " of ME"
          << ((theEndcap == 1) ? "+" : "-") << theStation << "/" << theRing
          << "/" << theChamber << " (trig. sector " << theSector
          << " subsector " << theSubsector << " id " << theTrigChamber << ")";
        for (std::vector<CSCWireDigi>::iterator pld = digiV[i_layer].begin();
             pld != digiV[i_layer].end(); pld++) {
          LogTrace("CSCAnodeLCTProcessor") << "   " << (*pld);
        }
      }
    }
  }

  return noDigis;
}

void CSCAnodeLCTProcessor::getDigis(const CSCWireDigiCollection* wiredc,
                                    const CSCDetId& id) {
  const CSCWireDigiCollection::Range rwired = wiredc->get(id);
  for (CSCWireDigiCollection::const_iterator digiIt = rwired.first;
       digiIt != rwired.second; ++digiIt) {
    digiV[id.layer()-1].push_back(*digiIt);
  }
}

void CSCAnodeLCTProcessor::readWireDigis(std::vector<int> wire[CSCConstants::NUM_LAYERS][CSCConstants::MAX_NUM_WIRES]) {
  /* Gets wire times from the wire digis and fills wire[][] vector */

  // Loop over all 6 layers.
  for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++) {
    // Loop over all digis in the layer and find the wireGroup and bx
    // time for each.
    for (std::vector<CSCWireDigi>::iterator pld = digiV[i_layer].begin();
         pld != digiV[i_layer].end(); pld++) {
      int i_wire  = pld->getWireGroup()-1;
      std::vector<int> bx_times = pld->getTimeBinsOn();

      // Check that the wires and times are appropriate.
      if (i_wire < 0 || i_wire >= numWireGroups) {
        if (infoV >= 0) edm::LogWarning("L1CSCTPEmulatorWrongInput")
          << "+++ Found wire digi with wrong wire number = " << i_wire
          << " (max wires = " << numWireGroups << "); skipping it... +++\n";
        continue;
      }
      // Accept digis in expected time window.  Total number of time
      // bins in DAQ readout is given by fifo_tbins, which thus
      // determines the maximum length of time interval.  Anode raw
      // hits in DAQ readout start (fifo_pretrig - 6) clocks before
      // L1Accept.  If times earlier than L1Accept were recorded, we
      // use them since they can modify the ALCTs found later, via
      // ghost-cancellation logic.
      int last_time = -999;
      if (bx_times.size() == fifo_tbins) {
        wire[i_layer][i_wire].push_back(0);        
        wire[i_layer][i_wire].push_back(6);
      }
      else {
        for (unsigned int i = 0; i < bx_times.size(); i++) {
          // Find rising edge change
          if (i > 0 && bx_times[i] == (bx_times[i-1]+1)) continue;
          if (bx_times[i] < static_cast<int>(fifo_tbins)) {
            if (infoV > 2) LogTrace("CSCAnodeLCTProcessor")
                             << "Digi on layer " << i_layer << " wire " << i_wire
                             << " at time " << bx_times[i];

            // Finally save times of hit wires.  One shot module will
            // not restart if a new pulse comes before the expiration
            // of the 6-bx period.
            if (last_time < 0 || ((bx_times[i]-last_time) >= 6) ) {
              wire[i_layer][i_wire].push_back(bx_times[i]);
              last_time = bx_times[i];
            }
          }
          else {
            if (infoV > 1) LogTrace("CSCAnodeLCTProcessor")
                             << "+++ Skipping wire digi: wire = " << i_wire
                             << " layer = " << i_layer << ", bx = " << bx_times[i] << " +++";
          }
        }
      }
    }
  }
}

bool CSCAnodeLCTProcessor::pulseExtension(const std::vector<int> wire[CSCConstants::NUM_LAYERS][CSCConstants::MAX_NUM_WIRES]){
  /* A pulse array will be used as a bit representation of hit times.
     For example: if a keywire has a bx_time of 3, then 1 shifted
     left 3 will be bit pattern 0000000000001000.  Bits are then added to
     signify the duration of a signal (hit_persist, formerly bx_width).  So
     for the pulse with a hit_persist of 6 will look like 0000000111111000. */

  bool chamber_empty = true;
  int i_wire, i_layer, digi_num;
  static unsigned int bits_in_pulse = 8*sizeof(pulse[0][0]);

  for (i_wire = 0; i_wire < numWireGroups; i_wire++) {
    for (i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++) {
      pulse[i_layer][i_wire] = 0;
    }
    first_bx[i_wire] = -999;
    first_bx_corrected[i_wire] = -999;
    for (int j = 0; j < 3; j++) quality[i_wire][j] = -999;
  }

  for (i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++){
    digi_num = 0;
    for (i_wire = 0; i_wire < numWireGroups; i_wire++) {
      if (wire[i_layer][i_wire].size() > 0) {
        std::vector<int> bx_times = wire[i_layer][i_wire];
        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 wire digi (wire = " << i_wire
              << " 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;
          }

          // Found at least one in-time digi; set chamber_empty to false
          if (chamber_empty) chamber_empty = false;

          // make the pulse
          for (unsigned int bx = bx_times[i];
               bx < (bx_times[i] + hit_persist); bx++)
          pulse[i_layer][i_wire] = pulse[i_layer][i_wire] | (1 << bx);

          // Debug information.
          if (infoV > 1) {
            LogTrace("CSCAnodeLCTProcessor")
              << "Wire digi: layer " << i_layer
              << " digi #" << ++digi_num << " wire group " << i_wire
              << " time " << bx_times[i];
            if (infoV > 2) {
              std::ostringstream strstrm;
              for (int i = 1; i <= 32; i++) {
                strstrm << ((pulse[i_layer][i_wire]>>(32-i)) & 1);
              }
              LogTrace("CSCAnodeLCTProcessor") << "  Pulse: " << strstrm.str();
            }
          }
        }
      }
    }
  }

  if (infoV > 1 && !chamber_empty) {
    dumpDigis(wire);
  }

  return chamber_empty;
}

bool CSCAnodeLCTProcessor::preTrigger(const int key_wire, const int start_bx) {
  /* Check that there are nplanes_hit_pretrig or more layers hit in collision
     or accelerator patterns for a particular key_wire.  If so, return
     true and the PatternDetection process will start. */

  unsigned int layers_hit;
  bool hit_layer[CSCConstants::NUM_LAYERS];
  int this_layer, this_wire;
  // If nplanes_hit_accel_pretrig is 0, the firmware uses the value
  // of nplanes_hit_pretrig instead.
  const unsigned int nplanes_hit_pretrig_acc =
    (nplanes_hit_accel_pretrig != 0) ? nplanes_hit_accel_pretrig :
    nplanes_hit_pretrig;
  const unsigned int pretrig_thresh[CSCConstants::NUM_ALCT_PATTERNS] = {
    nplanes_hit_pretrig_acc, nplanes_hit_pretrig, nplanes_hit_pretrig
  };

  // Loop over bx times, accelerator and collision patterns to 
  // look for pretrigger.
  // 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;
  for (unsigned int bx_time = start_bx; bx_time < stop_bx; bx_time++) {
    for (int i_pattern = 0; i_pattern < CSCConstants::NUM_ALCT_PATTERNS; i_pattern++) {
      for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++)
        hit_layer[i_layer] = false;
      layers_hit = 0;

      for (int i_wire = 0; i_wire < NUM_PATTERN_WIRES; i_wire++){
        if (pattern_mask[i_pattern][i_wire] != 0){
          this_layer = pattern_envelope[0][i_wire];
          this_wire  = pattern_envelope[1+MESelection][i_wire]+key_wire;
          if ((this_wire >= 0) && (this_wire < numWireGroups)){
            // Perform bit operation to see if pulse is 1 at a certain bx_time.
            if (((pulse[this_layer][this_wire] >> bx_time) & 1) == 1) {
              // Store number of layers hit.
              if (hit_layer[this_layer] == false){
                hit_layer[this_layer] = true;
                layers_hit++;
              }

              // See if number of layers hit is greater than or equal to
              // pretrig_thresh.
              if (layers_hit >= pretrig_thresh[i_pattern]) {
                first_bx[key_wire] = bx_time;
                if (infoV > 1) {
                  LogTrace("CSCAnodeLCTProcessor")
                    << "Pretrigger was satisfied for wire: " << key_wire
                    << " pattern: " << i_pattern
                    << " bx_time: " << bx_time;
                }
                return true;
              }
            }
          }
        }
      }
    }
  }
  // If the pretrigger was never satisfied, then return false.
  return false;
}

bool CSCAnodeLCTProcessor::patternDetection(const int key_wire) {
  /* See if there is a pattern that satisfies nplanes_hit_pattern number of
     layers hit for either the accelerator or collision patterns.  Use
     the pattern with the best quality. */

  bool trigger = false;
  bool hit_layer[CSCConstants::NUM_LAYERS];
  unsigned int temp_quality;
  int this_layer, this_wire, delta_wire;
  // If nplanes_hit_accel_pattern is 0, the firmware uses the value
  // of nplanes_hit_pattern instead.
  const unsigned int nplanes_hit_pattern_acc =
    (nplanes_hit_accel_pattern != 0) ? nplanes_hit_accel_pattern :
    nplanes_hit_pattern;
  const unsigned int pattern_thresh[CSCConstants::NUM_ALCT_PATTERNS] = {
    nplanes_hit_pattern_acc, nplanes_hit_pattern, nplanes_hit_pattern
  };
  const std::string ptn_label[] = {"Accelerator", "CollisionA", "CollisionB"};

  for (int i_pattern = 0; i_pattern < CSCConstants::NUM_ALCT_PATTERNS; i_pattern++){
    temp_quality = 0;
    for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++)
      hit_layer[i_layer] = false;

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

    for (int i_wire = 0; i_wire < NUM_PATTERN_WIRES; i_wire++){
      if (pattern_mask[i_pattern][i_wire] != 0){
        this_layer = pattern_envelope[0][i_wire];
        delta_wire = pattern_envelope[1+MESelection][i_wire];
        this_wire  = delta_wire + key_wire;
        if ((this_wire >= 0) && (this_wire < numWireGroups)){

          // Wait a drift_delay time later and look for layers hit in
          // the pattern.
          if ( ( (pulse[this_layer][this_wire] >> 
                 (first_bx[key_wire] + drift_delay)) & 1) == 1) {

            // If layer has never had a hit before, then increment number
            // of layer hits.
            if (hit_layer[this_layer] == false){
              temp_quality++;
              // keep track of which layers already had hits.
              hit_layer[this_layer] = true;
              if (infoV > 1)
                LogTrace("CSCAnodeLCTProcessor")
                  << "bx_time: " << first_bx[key_wire]
                  << " pattern: " << i_pattern << " keywire: " << key_wire
                  << " layer: "     << this_layer
                  << " quality: "   << temp_quality;
            }
            
            // for averaged time use only the closest WGs around the key WG
            if (abs(delta_wire)<2) {
              // find at what bx did pulse on this wire&layer start
              // use hit_pesrist constraint on how far back we can go
              int first_bx_layer = first_bx[key_wire] + drift_delay;
              for (unsigned int dbx=0; dbx<hit_persist; dbx++) {
                if (((pulse[this_layer][this_wire] >> (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("CSCAnodeLCTProcessor")
                  <<" 1st bx in layer: "<<first_bx_layer
                  <<" sum bx: "<<times_sum
                  <<" #pat. hits: "<<num_pattern_hits;
            }
          }
        }
      }
    }

    // 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_wire] = *im;
      else if ((sz % 2) == 1) first_bx_corrected[key_wire] = *(++im);
      else first_bx_corrected[key_wire] = ((*im) + (*(++im)))/2;
    
      if (infoV > 1) {
        char bxs[300]="";
        for (im = mset_for_median.begin(); im != mset_for_median.end(); im++) 
          sprintf(bxs,"%s %d", bxs, *im);
        LogTrace("CSCAnodeLCTProcessor")
          <<"bx="<<first_bx[key_wire]<<" bx_cor="<< first_bx_corrected[key_wire]<<"  bxset="<<bxs;
      }
    }

    if (temp_quality >= pattern_thresh[i_pattern]) {
      trigger = true;

      if (!isTMB07) {
        // Quality reported by the pattern detector is defined as the number
        // of the layers hit in a pattern minus (pattern_thresh-1) value.
        temp_quality -= (pattern_thresh[i_pattern]-1);
      }
      else {
        // Quality definition changed on 22 June 2007: it no longer depends
        // on pattern_thresh.
        int Q;
        // hack to run the Phase-II ME2/1, ME3/1 and ME4/1 ILT
        if (temp_quality == 3 and (runME21ILT_ or runME3141ILT_)) Q = 4;
        else if (temp_quality > 3) Q = temp_quality - 3;
        else                  Q = 0; // quality code 0 is valid!
        temp_quality = Q;
      }

      if (i_pattern == 0) {
        // Accelerator pattern
        quality[key_wire][0] = temp_quality;
      }
      else {
        // Only one collision pattern (of the best quality) is reported
        if (static_cast<int>(temp_quality) > quality[key_wire][1]) {
          quality[key_wire][1] = temp_quality;
          quality[key_wire][2] = i_pattern-1;
        }
      }
      if (infoV > 1) {
        LogTrace("CSCAnodeLCTProcessor")
          << "Pattern found; keywire: "  << key_wire
          << " type: " << ptn_label[i_pattern]
          << " quality: " << temp_quality << "\n";
      }
    }
  }
  if (infoV > 1 && quality[key_wire][1] > 0) {
    if (quality[key_wire][2] == 0)
      LogTrace("CSCAnodeLCTProcessor")
        << "Collision Pattern A is chosen" << "\n";
    else if (quality[key_wire][2] == 1)
      LogTrace("CSCAnodeLCTProcessor")
        << "Collision Pattern B is chosen" << "\n";
  }
  return trigger;
}

void CSCAnodeLCTProcessor::ghostCancellationLogic() {
  /* This function looks for LCTs on the previous and next wires.  If one
     exists and it has a better quality and a bx_time up to 4 clocks earlier
     than the present, then the present LCT is cancelled.  The present LCT
     also gets cancelled if it has the same quality as the one on the
     previous wire (this has not been done in 2003 test beam).  The
     cancellation is done separately for collision and accelerator patterns. */

  int ghost_cleared[CSCConstants::MAX_NUM_WIRES][2];

  for (int key_wire = 0; key_wire < numWireGroups; key_wire++) {
    for (int i_pattern = 0; i_pattern < 2; i_pattern++) {
      ghost_cleared[key_wire][i_pattern] = 0;

      // Non-empty wire group.
      int qual_this = quality[key_wire][i_pattern];
      if (qual_this > 0) {

        // Previous wire.
        int qual_prev = (key_wire > 0) ? quality[key_wire-1][i_pattern] : 0;
        if (qual_prev > 0) {
          int dt = first_bx[key_wire] - first_bx[key_wire-1];
          // Cancel this wire
          //   1) If the candidate at the previous wire is at the same bx
          //      clock and has better quality (or equal quality - this has
          //      been implemented only in 2004).
          //   2) If the candidate at the previous wire is up to 4 clocks
          //      earlier, regardless of quality.
          if (dt == 0) {
            if (qual_prev >= qual_this) ghost_cleared[key_wire][i_pattern] = 1;
          }
          else if (dt > 0 && dt <= ghost_cancellation_bx_depth ) {
            // Next "if" check accounts for firmware bug and should be
            // removed once the next firmware version is used.
            // The bug is fixed in 5/5/2008 version of ALCT firmware,
            // which is used in all chambers starting with 26/05/2008.
            if ((!ghost_cancellation_side_quality) ||
                (qual_prev > qual_this) )
              ghost_cleared[key_wire][i_pattern] = 1;
          }
        }

        // Next wire.
        // Skip this step if this wire is already declared "ghost".
        if (ghost_cleared[key_wire][i_pattern] == 1) {
          if (infoV > 1) LogTrace("CSCAnodeLCTProcessor")
            << ((i_pattern == 0) ? "Accelerator" : "Collision")
            << " pattern ghost cancelled on key_wire " << key_wire <<" q="<<qual_this
            << "  by wire " << key_wire-1<<" q="<<qual_prev;
          continue;
        }

        int qual_next =
          (key_wire < numWireGroups-1) ? quality[key_wire+1][i_pattern] : 0;
        if (qual_next > 0) {
          int dt = first_bx[key_wire] - first_bx[key_wire+1];
          // Same cancellation logic as for the previous wire.
          if (dt == 0) {
            if (qual_next > qual_this) ghost_cleared[key_wire][i_pattern] = 1;
          }
          else if (dt > 0 && dt <= ghost_cancellation_bx_depth ) {
            // Next "if" check accounts for firmware bug and should be
            // removed once the next firmware version is used.
            // The bug is fixed in 5/5/2008 version of ALCT firmware,
            // which is used in all chambers starting with 26/05/2008.
            if ((!ghost_cancellation_side_quality) ||
                (qual_next >= qual_this) )
              ghost_cleared[key_wire][i_pattern] = 1;
          }
        }
        if (ghost_cleared[key_wire][i_pattern] == 1) {
          if (infoV > 1) LogTrace("CSCAnodeLCTProcessor")
            << ((i_pattern == 0) ? "Accelerator" : "Collision")
            << " pattern ghost cancelled on key_wire " << key_wire <<" q="<<qual_this
            << "  by wire " << key_wire+1<<" q="<<qual_next;
          continue;
        }
      }
    }
  }

  // All cancellation is done in parallel, so wiregroups do not know what
  // their neighbors are cancelling.
  for (int key_wire = 0; key_wire < numWireGroups; key_wire++) {
    for (int i_pattern = 0; i_pattern < 2; i_pattern++) {
      if (ghost_cleared[key_wire][i_pattern] > 0) {
        clear(key_wire, i_pattern);
      }
    }
  }
}


void CSCAnodeLCTProcessor::ghostCancellationLogicSLHC() {
  /* This function looks for LCTs on the previous and next wires.  If one
     exists and it has a better quality and a bx_time up to
     ghost_cancellation_bx_depth clocks earlier than the present,
     then the present LCT is cancelled.  The present LCT
     also gets cancelled if it has the same quality as the one on the
     previous wire (this has not been done in 2003 test beam).  The
     cancellation is done separately for collision and accelerator patterns. */

  int ghost_cleared[CSCConstants::MAX_NUM_WIRES][2];

  for (int key_wire = 0; key_wire < numWireGroups; key_wire++) {
    for (int i_pattern = 0; i_pattern < 2; i_pattern++) {
      ghost_cleared[key_wire][i_pattern] = 0;

      // Non-empty wire group.
      int qual_this = quality[key_wire][i_pattern];
      if (qual_this > 0) {

    if (runME21ILT_ or runME3141ILT_) qual_this = (qual_this & 0x03); 
        // Previous wire.
        int dt = -1;
        int qual_prev = (key_wire > 0) ? quality[key_wire-1][i_pattern] : 0;
        if (qual_prev > 0) {
          if (use_corrected_bx)
            dt = first_bx_corrected[key_wire] - first_bx_corrected[key_wire-1];
          else
            dt = first_bx[key_wire] - first_bx[key_wire-1];
          // hack to run the Phase-II ME2/1, ME3/1 and ME4/1 ILT
          if (runME21ILT_ or runME3141ILT_) qual_prev = (qual_prev & 0x03); 

          // Cancel this wire
          //   1) If the candidate at the previous wire is at the same bx
          //      clock and has better quality (or equal? quality - this has
          //      been implemented only in 2004).
          //   2) If the candidate at the previous wire is up to 4 clocks
          //      earlier, regardless of quality.
          if (dt == 0) {
            if (qual_prev > qual_this) ghost_cleared[key_wire][i_pattern] = 1;
          }
          else if (dt > 0 && dt <= ghost_cancellation_bx_depth ) {
            // Next "if" check accounts for firmware bug and should be
            // removed once the next firmware version is used.
            // The bug is fixed in 5/5/2008 version of ALCT firmware,
            // which is used in all chambers starting with 26/05/2008.
            if ((!ghost_cancellation_side_quality) ||
                (qual_prev > qual_this) )
              ghost_cleared[key_wire][i_pattern] = 1;
          }
        }

        // Next wire.
        // Skip this step if this wire is already declared "ghost".
        if (ghost_cleared[key_wire][i_pattern] == 1) {
          if (infoV > 1) LogTrace("CSCAnodeLCTProcessor")
            << ((i_pattern == 0) ? "Accelerator" : "Collision")
            << " pattern ghost cancelled on key_wire " << key_wire <<" q="<<qual_this
            << "  by wire " << key_wire-1<<" q="<<qual_prev<<"  dt="<<dt;
          continue;
        }

        dt = -1;
        int qual_next =
          (key_wire < numWireGroups-1) ? quality[key_wire+1][i_pattern] : 0;
        if (qual_next > 0) {
          if (use_corrected_bx)
            dt = first_bx_corrected[key_wire] - first_bx_corrected[key_wire+1];
          else
            dt = first_bx[key_wire] - first_bx[key_wire+1];
          // hack to run the Phase-II ME2/1, ME3/1 and ME4/1 ILT
          if (runME21ILT_ or runME3141ILT_)
            qual_next = (qual_next & 0x03);
          // Same cancellation logic as for the previous wire.
          if (dt == 0) {
            if (qual_next >= qual_this) ghost_cleared[key_wire][i_pattern] = 1;
          }
          else if (dt > 0 && dt <= ghost_cancellation_bx_depth ) {
            // Next "if" check accounts for firmware bug and should be
            // removed once the next firmware version is used.
            // The bug is fixed in 5/5/2008 version of ALCT firmware,
            // which is used in all chambers starting with 26/05/2008.
            if ((!ghost_cancellation_side_quality) ||
                (qual_next >= qual_this) )
              ghost_cleared[key_wire][i_pattern] = 1;
          }
        }
        if (ghost_cleared[key_wire][i_pattern] == 1) {
          if (infoV > 1) LogTrace("CSCAnodeLCTProcessor")
            << ((i_pattern == 0) ? "Accelerator" : "Collision")
            << " pattern ghost cancelled on key_wire " << key_wire <<" q="<<qual_this
            << "  by wire " << key_wire+1<<" q="<<qual_next<<"  dt="<<dt;
          continue;
        }
      }
    }
  }

  // All cancellation is done in parallel, so wiregroups do not know what
  // their neighbors are cancelling.
  for (int key_wire = 0; key_wire < numWireGroups; key_wire++) {
    for (int i_pattern = 0; i_pattern < 2; i_pattern++) {
      if (ghost_cleared[key_wire][i_pattern] > 0) {
        clear(key_wire, i_pattern);
      }
    }
  }
}


void CSCAnodeLCTProcessor::lctSearch() {
  // First modify the quality according accel_mode, then store all
  // of the valid LCTs in an array.
  std::vector<CSCALCTDigi> lct_list;

  for (int i_wire = 0; i_wire < numWireGroups; i_wire++) {
    // If there is either accelerator or collision, perform trigMode
    // function before storing and sorting.
    if (quality[i_wire][0] > 0 || quality[i_wire][1] > 0) {
      trigMode(i_wire);

      int bx  = first_bx[i_wire];
      int fbx = first_bx_corrected[i_wire];
      if (infoV>1) LogTrace("CSCAnodeLCTProcessor")<<" bx="<<bx<<" fbx="<<fbx;
      if (use_corrected_bx) {
        bx  = fbx;
        fbx = first_bx[i_wire];
      }
      if (infoV>1) LogTrace("CSCAnodeLCTProcessor")<<" bx="<<bx<<" fbx="<<fbx;
      // Store any valid accelerator pattern LCTs.
      if (quality[i_wire][0] > 0) {
        int qual = (quality[i_wire][0] & 0x03); // 2 LSBs
        CSCALCTDigi lct_info(1, qual, 1, 0, i_wire, bx);
        lct_info.setFullBX(fbx);
        lct_list.push_back(lct_info);
      }

      // Store any valid collision pattern LCTs.
      if (quality[i_wire][1] > 0) {
        int qual = (quality[i_wire][1] & 0x03); // 2 LSBs
        CSCALCTDigi lct_info(1, qual, 0, quality[i_wire][2], i_wire, bx);
        //lct_info.setFullBX(fbx); // uncomment if one wants, e.g., to keep corrected time here
        lct_list.push_back(lct_info);
        if (infoV>1) LogTrace("CSCAnodeLCTProcessor")<<" got lct_info: "<<lct_info;
      }

      // Modify qualities according to accel_mode parameter.
      accelMode(i_wire);
    }
  }

  // Best track selector selects two collision and two accelerator ALCTs
  // with the best quality per time bin.
  std::vector<CSCALCTDigi> fourBest = bestTrackSelector(lct_list);

  if (infoV > 0) {
    int n_alct_all=0, n_alct=0;
    for (std::vector <CSCALCTDigi>::const_iterator plct = lct_list.begin(); plct != lct_list.end(); plct++)
      if (plct->isValid() && plct->getBX()==6) n_alct_all++;
    for (std::vector <CSCALCTDigi>::const_iterator plct = fourBest.begin(); plct != fourBest.end(); plct++)
      if (plct->isValid() && plct->getBX()==6) n_alct++;

    LogTrace("CSCAnodeLCTProcessor")<<"alct_count E:"<<theEndcap<<"S:"<<theStation<<"R:"<<theRing<<"C:"<<theChamber
      <<"  all "<<n_alct_all<<"  found "<<n_alct;
  }
  
  // Select two best of four per time bin, based on quality and
  // accel_mode parameter.
  for (std::vector<CSCALCTDigi>::const_iterator plct = fourBest.begin();
       plct != fourBest.end(); plct++) {

    int bx = plct->getBX();
    if (bx >= MAX_ALCT_BINS) {
      if (infoV > 0) edm::LogWarning("L1CSCTPEmulatorOutOfTimeALCT")
        << "+++ Bx of ALCT candidate, " << bx << ", exceeds max allowed, "
        << MAX_ALCT_BINS-1 << "; skipping it... +++\n";
      continue;
    }

    if (isBetterALCT(*plct, bestALCT[bx])) {
      if (isBetterALCT(bestALCT[bx], secondALCT[bx])) {
        secondALCT[bx] = bestALCT[bx];
      }
      bestALCT[bx] = *plct;
    }
    else if (isBetterALCT(*plct, secondALCT[bx])) {
      secondALCT[bx] = *plct;
    }
  }

  if (!isTMB07) {
    // Prior to DAQ-2006 format, only ALCTs at the earliest bx were reported.
    int first_bx = MAX_ALCT_BINS;
    for (int bx = 0; bx < MAX_ALCT_BINS; bx++) {
      if (bestALCT[bx].isValid()) {
        first_bx = bx;
        break;
      }
    }
    if (first_bx < MAX_ALCT_BINS) {
      for (int bx = first_bx + 1; bx < MAX_ALCT_BINS; bx++) {
        if (bestALCT[bx].isValid())   bestALCT[bx].clear();
        if (secondALCT[bx].isValid()) secondALCT[bx].clear();
      }
    }
  }

  for (int bx = 0; bx < MAX_ALCT_BINS; bx++) {
    if (bestALCT[bx].isValid()) {
      bestALCT[bx].setTrknmb(1);
      if (infoV > 0) {
        LogDebug("CSCAnodeLCTProcessor")
          << "\n" << bestALCT[bx] << " fullBX = "<<bestALCT[bx].getFullBX()
          << " found in ME"
          << ((theEndcap == 1) ? "+" : "-")
          << theStation << "/" << theRing << "/" << theChamber
          << " (sector " << theSector << " subsector " << theSubsector
          << " trig id. " << theTrigChamber << ")" << "\n";
      }
      if (secondALCT[bx].isValid()) {
        secondALCT[bx].setTrknmb(2);
        if (infoV > 0) {
          LogDebug("CSCAnodeLCTProcessor")
            << secondALCT[bx] << " fullBX = "<<secondALCT[bx].getFullBX()
            << " found in ME"
            << ((theEndcap == 1) ? "+" : "-")
            << theStation << "/" << theRing << "/" << theChamber
            << " (sector " << theSector << " subsector " << theSubsector
            << " trig id. " << theTrigChamber << ")" << "\n";
        }
      }
    }
  }
}

std::vector<CSCALCTDigi> CSCAnodeLCTProcessor::bestTrackSelector(
                                 const std::vector<CSCALCTDigi>& all_alcts) {
  /* Selects two collision and two accelerator ALCTs per time bin with
     the best quality. */
  CSCALCTDigi bestALCTs[MAX_ALCT_BINS][2], secondALCTs[MAX_ALCT_BINS][2];

  if (infoV > 1) {
    LogTrace("CSCAnodeLCTProcessor") << all_alcts.size() <<
      " ALCTs at the input of best-track selector: ";
    for (std::vector <CSCALCTDigi>::const_iterator plct = all_alcts.begin();
         plct != all_alcts.end(); plct++) {
      if (!plct->isValid()) continue;
      LogTrace("CSCAnodeLCTProcessor") << (*plct);
    }
  }

  CSCALCTDigi tA[MAX_ALCT_BINS][2], tB[MAX_ALCT_BINS][2];
  for (std::vector <CSCALCTDigi>::const_iterator plct = all_alcts.begin();
       plct != all_alcts.end(); plct++) {
    if (!plct->isValid()) continue;

    // Select two collision and two accelerator ALCTs with the highest
    // quality at every bx.  The search for best ALCTs is done in parallel
    // for collision and accelerator patterns, and simultaneously for
    // two ALCTs, tA and tB.  If two or more ALCTs have equal qualities,
    // the priority is given to the ALCT with larger wiregroup number
    // in the search for tA (collision and accelerator), and to the ALCT
    // with smaller wiregroup number in the search for tB.
    int bx    = (*plct).getBX();
    int accel = (*plct).getAccelerator();
    int qual  = (*plct).getQuality();
    int wire  = (*plct).getKeyWG();
    bool vA = tA[bx][accel].isValid();
    bool vB = tB[bx][accel].isValid();
    int qA  = tA[bx][accel].getQuality();
    int qB  = tB[bx][accel].getQuality();
    int wA  = tA[bx][accel].getKeyWG();
    int wB  = tB[bx][accel].getKeyWG();
    if (!vA || qual > qA || (qual == qA && wire > wA)) {
      tA[bx][accel] = *plct;
    }
    if (!vB || qual > qB || (qual == qB && wire < wB)) {
      tB[bx][accel] = *plct;
    }
  }

  for (int bx = 0; bx < MAX_ALCT_BINS; bx++) {
    for (int accel = 0; accel <= 1; accel++) {
      // Best ALCT is always tA.
      if (tA[bx][accel].isValid()) {
        if (infoV > 2) {
          LogTrace("CSCAnodeLCTProcessor") << "tA: " << tA[bx][accel];
          LogTrace("CSCAnodeLCTProcessor") << "tB: " << tB[bx][accel];
        }
        bestALCTs[bx][accel] = tA[bx][accel];

        // If tA exists, tB exists too.
        if (tA[bx][accel] != tB[bx][accel] &&
            tA[bx][accel].getQuality() == tB[bx][accel].getQuality()) {
          secondALCTs[bx][accel] = tB[bx][accel];
        }
        else {
          // Funny part: if tA and tB are the same, or the quality of tB
          // is inferior to the quality of tA, the second best ALCT is
          // not tB.  Instead it is the largest-wiregroup ALCT among those
          // ALCT whose qualities are lower than the quality of the best one.
          for (std::vector <CSCALCTDigi>::const_iterator plct =
                 all_alcts.begin(); plct != all_alcts.end(); plct++) {
            if ((*plct).isValid() && 
                (*plct).getAccelerator() == accel && (*plct).getBX() == bx &&
                (*plct).getQuality() <  bestALCTs[bx][accel].getQuality() && 
                (*plct).getQuality() >= secondALCTs[bx][accel].getQuality() &&
                (*plct).getKeyWG()   >= secondALCTs[bx][accel].getKeyWG()) {
              secondALCTs[bx][accel] = *plct;
            }
          }
        }
      }
    }
  }

  // Fill the vector with up to four best ALCTs per bx and return it.
  std::vector<CSCALCTDigi> fourBest;
  for (int bx = 0; bx < MAX_ALCT_BINS; bx++) {
    for (int i = 0; i < 2; i++) {
      if (bestALCTs[bx][i].isValid())   fourBest.push_back(bestALCTs[bx][i]);
    }
    for (int i = 0; i < 2; i++) {
      if (secondALCTs[bx][i].isValid()) fourBest.push_back(secondALCTs[bx][i]);
    }
  }

  if (infoV > 1) {
    LogTrace("CSCAnodeLCTProcessor") << fourBest.size() << " ALCTs selected: ";
    for (std::vector<CSCALCTDigi>::const_iterator plct = fourBest.begin();
         plct != fourBest.end(); plct++) {
      LogTrace("CSCAnodeLCTProcessor") << (*plct);
    }
  }

  return fourBest;
}

bool CSCAnodeLCTProcessor::isBetterALCT(const CSCALCTDigi& lhsALCT,
                                        const CSCALCTDigi& rhsALCT) {
  /* This method should have been an overloaded > operator, but we
     have to keep it here since need to check values in quality[][]
     array modified according to accel_mode parameter. */
  bool returnValue = false;

  if (lhsALCT.isValid() && !rhsALCT.isValid()) {return true;}

  // ALCTs found at earlier bx times are ranked higher than ALCTs found at
  // later bx times regardless of the quality.
  if (lhsALCT.getBX()  < rhsALCT.getBX()) {returnValue = true;}
  if (lhsALCT.getBX() != rhsALCT.getBX()) {return returnValue;}

  // First check the quality of ALCTs.
  int qual1 = lhsALCT.getQuality();
  int qual2 = rhsALCT.getQuality();
  if (qual1 >  qual2) {returnValue = true;}
  // If qualities are the same, check accelerator bits of both ALCTs.
  // If they are not the same, rank according to accel_mode value.
  // If they are the same, keep the track selector assignment.
  else if (qual1 == qual2 && 
           lhsALCT.getAccelerator() != rhsALCT.getAccelerator() &&
           quality[lhsALCT.getKeyWG()][1-lhsALCT.getAccelerator()] >
           quality[rhsALCT.getKeyWG()][1-rhsALCT.getAccelerator()])
    {returnValue = true;}

  return returnValue;
}

void CSCAnodeLCTProcessor::trigMode(const int key_wire) {
  /* Function which enables/disables either collision or accelerator tracks.
     The function uses the trig_mode parameter to decide. */

  switch(trig_mode) {
  default:
  case 0:
    // Enables both collision and accelerator tracks
    break;
  case 1:
    // Disables collision tracks
    if (quality[key_wire][1] > 0) {
      quality[key_wire][1] = 0;
      if (infoV > 1) LogTrace("CSCAnodeLCTProcessor")
        << "trigMode(): collision track " << key_wire << " disabled" << "\n";
    }
    break;
  case 2:
    // Disables accelerator tracks
    if (quality[key_wire][0] > 0) {
      quality[key_wire][0] = 0;
      if (infoV > 1) LogTrace("CSCAnodeLCTProcessor")
        << "trigMode(): accelerator track " << key_wire << " disabled" << "\n";
    }
    break;
  case 3:
    // Disables collision track if there is an accelerator track found
    // in the same wire group at the same time
    if (quality[key_wire][0] > 0 && quality[key_wire][1] > 0) {
      quality[key_wire][1] = 0;
      if (infoV > 1) LogTrace("CSCAnodeLCTProcessor")
        << "trigMode(): collision track " << key_wire << " disabled" << "\n";
    }
    break;
  }
}

void CSCAnodeLCTProcessor::accelMode(const int key_wire) {
  /* Function which gives a preference either to the collision patterns
     or accelerator patterns.  The function uses the accel_mode parameter
     to decide. */
  int promotionBit = 1 << 2;

  switch(accel_mode) {
  default:
  case 0:
    // Ignore accelerator muons.
    if (quality[key_wire][0] > 0) {
      quality[key_wire][0] = 0;
      if (infoV > 1) LogTrace("CSCAnodeLCTProcessor")
        << "alctMode(): accelerator track " << key_wire << " ignored" << "\n";
    }
    break;
  case 1:
    // Prefer collision muons by adding promotion bit.
    if (quality[key_wire][1] > 0) {
      quality[key_wire][1] += promotionBit;
      if (infoV > 1) LogTrace("CSCAnodeLCTProcessor")
        << "alctMode(): collision track " << key_wire << " promoted" << "\n";
    }
    break;
  case 2:
    // Prefer accelerator muons by adding promotion bit.
    if (quality[key_wire][0] > 0) {
      quality[key_wire][0] += promotionBit;
      if (infoV > 1) LogTrace("CSCAnodeLCTProcessor")
        << "alctMode(): accelerator track " << key_wire << " promoted"<< "\n";
    }
    break;
  case 3:
    // Ignore collision muons.
    if (quality[key_wire][1] > 0) {
      quality[key_wire][1] = 0;
      if (infoV > 1) LogTrace("CSCAnodeLCTProcessor")
        << "alctMode(): collision track " << key_wire << " ignored" << "\n";
    }
    break;
  }
}

// Dump of configuration parameters.
void CSCAnodeLCTProcessor::dumpConfigParams() const {
  std::ostringstream strm;
  strm << "\n";
  strm << "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n";
  strm << "+                  ALCT 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 anode raw hits in DAQ readout] = "
       << fifo_pretrig << "\n";
  strm << " drift_delay  [drift delay after pre-trigger, in 25 ns bins] = "
       << 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 << " nplanes_hit_accel_pretrig [min. number of layers hit for accel."
       << " pre-trig.] = " << nplanes_hit_accel_pretrig << "\n";
  strm << " nplanes_hit_accel_pattern [min. number of layers hit for accel."
       << " trigger] = "   << nplanes_hit_accel_pattern << "\n";
  strm << " trig_mode  [enabling/disabling collision/accelerator tracks] = "
       << trig_mode << "\n";
  strm << " accel_mode [preference to collision/accelerator tracks] = "
       << accel_mode << "\n";
  strm << " l1a_window_width [L1Accept window width, in 25 ns bins] = "
       << l1a_window_width << "\n";
  strm << "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n";
  LogDebug("CSCAnodeLCTProcessor") << strm.str();
  //std::cout<<strm.str()<<std::endl;
}

// Dump of digis on wire groups.
void CSCAnodeLCTProcessor::dumpDigis(const std::vector<int> wire[CSCConstants::NUM_LAYERS][CSCConstants::MAX_NUM_WIRES]) const {
  LogDebug("CSCAnodeLCTProcessor")
    << "ME" << ((theEndcap == 1) ? "+" : "-")
    << theStation << "/" << theRing << "/" << theChamber
    << " nWiregroups " << numWireGroups;

  std::ostringstream strstrm;
  for (int i_wire = 0; i_wire < numWireGroups; i_wire++) {
    if (i_wire%10 == 0) {
      if (i_wire < 100) strstrm << i_wire/10;
      else              strstrm << (i_wire-100)/10;
    }
    else                strstrm << " ";
  }
  strstrm << "\n";
  for (int i_wire = 0; i_wire < numWireGroups; i_wire++) {
    strstrm << i_wire%10;
  }
  for (int i_layer = 0; i_layer < CSCConstants::NUM_LAYERS; i_layer++) {
    strstrm << "\n";
    for (int i_wire = 0; i_wire < numWireGroups; i_wire++) {
      if (wire[i_layer][i_wire].size() > 0) {
        std::vector<int> bx_times = wire[i_layer][i_wire];
        strstrm << std::hex << bx_times[0] << std::dec;
      }
      else {
        strstrm << ".";
      }
    }
  }
  LogTrace("CSCAnodeLCTProcessor") << strstrm.str();
}

// Returns vector of read-out ALCTs, if any.  Starts with the vector of
// all found ALCTs and selects the ones in the read-out time window.
std::vector<CSCALCTDigi> CSCAnodeLCTProcessor::readoutALCTs() {
  std::vector<CSCALCTDigi> tmpV;

  // The number of LCT bins in the read-out is given by the
  // l1a_window_width parameter, but made even by setting the LSB of
  // l1a_window_width to 0.
  static int lct_bins   = 
    //    (l1a_window_width%2 == 0) ? l1a_window_width : l1a_window_width-1;
    l1a_window_width;
  static int late_tbins = early_tbins + lct_bins;

  static int ifois = 0;
  if (ifois == 0) {

    //std::cout<<"ALCT early_tbins="<<early_tbins<<"  lct_bins="<<lct_bins<<"  l1a_window_width="<<l1a_window_width<<"  late_tbins="<<late_tbins<<std::endl;
    //std::cout<<"**** ALCT readoutALCTs config dump ****"<<std::endl;
    //dumpConfigParams();

    if (infoV >= 0 && early_tbins < 0) {
      edm::LogWarning("L1CSCTPEmulatorSuspiciousParameters")
        << "+++ fifo_pretrig = " << fifo_pretrig
        << "; in-time ALCTs are not getting read-out!!! +++" << "\n";
    }

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

  // Start from the vector of all found ALCTs and select those within
  // the ALCT*L1A coincidence window.
  std::vector<CSCALCTDigi> all_alcts = getALCTs();
  for (std::vector <CSCALCTDigi>::const_iterator plct = all_alcts.begin();
       plct != all_alcts.end(); plct++) {
    if (!plct->isValid()) continue;

    int bx = (*plct).getBX();
    // Skip ALCTs found too early relative to L1Accept.
    if (bx <= early_tbins) {
      if (infoV > 1) LogDebug("CSCAnodeLCTProcessor")
        << " Do not report ALCT on keywire " << plct->getKeyWG()
        << ": found at bx " << bx << ", whereas the earliest allowed bx is "
        << early_tbins+1;
      continue;
    }

    // Skip ALCTs found too late relative to L1Accept.
    if (bx > late_tbins) {
      if (infoV > 1) LogDebug("CSCAnodeLCTProcessor")
        << " Do not report ALCT on keywire " << plct->getKeyWG()
        << ": found at bx " << bx << ", whereas the latest allowed bx is "
        << late_tbins;
      continue;
    }

    tmpV.push_back(*plct);
  }
  return tmpV;
}

// Returns vector of all found ALCTs, if any.  Used in ALCT-CLCT matching.
std::vector<CSCALCTDigi> CSCAnodeLCTProcessor::getALCTs() {
  std::vector<CSCALCTDigi> tmpV;
  for (int bx = 0; bx < MAX_ALCT_BINS; bx++) {
    if (bestALCT[bx].isValid())   tmpV.push_back(bestALCT[bx]);
    if (secondALCT[bx].isValid()) tmpV.push_back(secondALCT[bx]);
  }
  return tmpV;
}


void CSCAnodeLCTProcessor::showPatterns(const int key_wire) {
  /* Method to test the pretrigger */
  for (int i_pattern = 0; i_pattern < CSCConstants::NUM_ALCT_PATTERNS;
       i_pattern++) {
    std::ostringstream strstrm_header;
    LogTrace("CSCAnodeLCTProcessor")
      << "\n" << "Pattern: " << i_pattern << " Key wire: " << key_wire;
    for (int i = 1; i <= 32; i++) {
      strstrm_header << ((32-i)%10);
    }
    LogTrace("CSCAnodeLCTProcessor") << strstrm_header.str();
    for (int i_wire = 0; i_wire < NUM_PATTERN_WIRES; i_wire++) {
      if (pattern_mask[i_pattern][i_wire] != 0) {
        std::ostringstream strstrm_pulse;
        int this_layer = pattern_envelope[0][i_wire];
        int this_wire  = pattern_envelope[1+MESelection][i_wire]+key_wire;
        if (this_wire >= 0 && this_wire < numWireGroups) {
          for (int i = 1; i <= 32; i++) {
            strstrm_pulse << ((pulse[this_layer][this_wire]>>(32-i)) & 1);
          }
          LogTrace("CSCAnodeLCTProcessor")
            << strstrm_pulse.str() << " on layer " << this_layer;
        }
      }
    }
    LogTrace("CSCAnodeLCTProcessor")
      << "-------------------------------------------";
  }
}