#include <CSCUpgradeCathodeLCTProcessor.h>

Inheritance diagram for CSCUpgradeCathodeLCTProcessor:

Public Member Functions
	CSCUpgradeCathodeLCTProcessor (unsigned endcap, unsigned station, unsigned sector, unsigned subsector, unsigned chamber, const edm::ParameterSet &conf)

Public Member Functions inherited from CSCCathodeLCTProcessor
void	clear ()

	CSCCathodeLCTProcessor (unsigned endcap, unsigned station, unsigned sector, unsigned subsector, unsigned chamber, const edm::ParameterSet &conf)

CSCCLCTDigi	getBestCLCT (int bx) const

std::vector< CSCCLCTDigi >	getCLCTs () const

unsigned	getInTimeHMT () const

unsigned	getOutTimeHMT () const

CSCCLCTDigi	getSecondCLCT (int bx) const

std::vector< int >	preTriggerBXs () const

std::vector< CSCCLCTPreTriggerDigi >	preTriggerDigis () const

std::vector< CSCCLCTDigi >	readoutCLCTs () const

CSCShowerDigi	readoutShower () const

std::vector< CSCCLCTDigi >	run (const CSCComparatorDigiCollection *compdc)

void	run (const std::vector< int > halfstrip[CSCConstants::NUM_LAYERS][CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER])

void	setConfigParameters (const CSCDBL1TPParameters *conf)

void	setESLookupTables (const CSCL1TPLookupTableCCLUT *conf)

	~CSCCathodeLCTProcessor () override=default

Public Member Functions inherited from CSCBaseboard
	CSCBaseboard (unsigned endcap, unsigned station, unsigned sector, unsigned subsector, unsigned chamber, const edm::ParameterSet &conf)

	CSCBaseboard ()

std::string	getCSCName () const

CSCDetId	id () const

void	setCSCGeometry (const CSCGeometry *g)

virtual	~CSCBaseboard ()=default

Private Member Functions
std::vector< CSCCLCTDigi >	findLCTs (const std::vector< int > halfstrip[CSCConstants::NUM_LAYERS][CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER]) override

void	markBusyZone (const int bx)

void	markPreTriggerZone (bool pretrig_zone[CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER]) const

bool	preTrigger (const int start_bx, int &first_bx) override

Private Attributes
bool	busyMap_ [CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER][CSCConstants::MAX_CLCT_TBINS]

unsigned int	clct_state_machine_zone_

unsigned int	pretrig_trig_zone_

bool	use_dead_time_zoning_

Additional Inherited Members
Protected Member Functions inherited from CSCCathodeLCTProcessor
void	checkConfigParameters ()

void	cleanComparatorContainer (CSCCLCTDigi &lct) const

void	clearPreTriggers ()

CSCCLCTDigi	constructCLCT (const int bx, const unsigned halfstrip_withstagger, const CSCCLCTDigi::ComparatorContainer &hits)

CSCCLCTPreTriggerDigi	constructPreCLCT (const int bx, const unsigned halfstrip, const unsigned index) const

void	dumpConfigParams () const

void	dumpDigis (const std::vector< int > strip[CSCConstants::NUM_LAYERS][CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER]) const

void	encodeHighMultiplicityBits (const std::vector< int > halfstrip[CSCConstants::NUM_LAYERS][CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER])

bool	getDigis (const CSCComparatorDigiCollection *compdc)

void	getDigis (const CSCComparatorDigiCollection *compdc, const CSCDetId &id)

void	markBusyKeys (const int best_hstrip, const int best_patid, int quality[CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER])

bool	patternFinding (const unsigned int bx_time, std::map< int, std::map< int, CSCCLCTDigi::ComparatorContainer > > &hits_in_patterns)

void	pulseExtension (const std::vector< int > time[CSCConstants::NUM_LAYERS][CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER])

void	readComparatorDigis (std::vector< int > halfstrip[CSCConstants::NUM_LAYERS][CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER])

void	setDefaultConfigParameters ()

Protected Member Functions inherited from CSCBaseboard
void	checkConfigParameters (unsigned int &var, const unsigned int var_max, const unsigned int var_def, const std::string &var_str)

Protected Attributes inherited from CSCCathodeLCTProcessor
unsigned int	best_pid [CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER]

CSCCLCTDigi	bestCLCT [CSCConstants::MAX_CLCT_TBINS]

std::unique_ptr< ComparatorCodeLUT >	cclut_

CSCPatternBank::LCTPatterns	clct_pattern_ = {}

std::vector< CSCComparatorDigi >	digiV [CSCConstants::NUM_LAYERS]

unsigned int	drift_delay

int	early_tbins

unsigned int	fifo_pretrig

unsigned int	fifo_tbins

unsigned int	hit_persist

unsigned	inTimeHMT_

bool	ispretrig_ [CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER]

unsigned int	min_separation

unsigned	minLayersCentralTBin_

unsigned int	nhits [CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER]

unsigned int	nplanes_hit_pattern

unsigned int	nplanes_hit_pretrig

int	numCFEBs_

int	numHalfStrips_

int	numStrips_

unsigned	outTimeHMT_

unsigned int	pid_thresh_pretrig

PulseArray	pulse_

std::unique_ptr< LCTQualityControl >	qualityControl_

bool	readout_earliest_2

CSCCLCTDigi	secondCLCT [CSCConstants::MAX_CLCT_TBINS]

CSCShowerDigi	shower_

unsigned	showerMaxInTBin_

unsigned	showerMaxOutTBin_

unsigned	showerMinInTBin_

unsigned	showerMinOutTBin_

int	stagger [CSCConstants::NUM_LAYERS]

int	start_bx_shift

std::vector< int >	thePreTriggerBXs

std::vector< CSCCLCTPreTriggerDigi >	thePreTriggerDigis

std::vector< unsigned >	thresholds_

unsigned int	tmb_l1a_window_size

Protected Attributes inherited from CSCBaseboard
edm::ParameterSet	alctParams_

edm::ParameterSet	clctParams_

edm::ParameterSet	commonParams_

const CSCChamber *	cscChamber_

const CSCGeometry *	cscGeometry_

CSCDetId	cscId_

bool	disableME1a_

bool	enableAlctPhase2_

bool	gangedME1a_

int	infoV

bool	isME11_

bool	isME12_

bool	isME13_

bool	isME21_

bool	isME22_

bool	isME31_

bool	isME32_

bool	isME41_

bool	isME42_

bool	run3_

bool	runCCLUT_

bool	runCCLUT_OTMB_

bool	runCCLUT_TMB_

bool	runME11ILT_

bool	runME11Up_

bool	runME21ILT_

bool	runME21Up_

bool	runME31Up_

bool	runME41Up_

bool	runPhase2_

edm::ParameterSet	showerParams_

unsigned	theChamber

std::string	theCSCName_

const unsigned	theEndcap

int	theRegion

unsigned	theRing

const unsigned	theSector

const unsigned	theStation

const unsigned	theSubsector

const unsigned	theTrigChamber

edm::ParameterSet	tmbParams_

Static Protected Attributes inherited from CSCCathodeLCTProcessor
static const unsigned int	def_drift_delay = 2

static const unsigned int	def_fifo_pretrig = 7

static const unsigned int	def_fifo_tbins = 12

static const unsigned int	def_hit_persist = 6

static const unsigned int	def_min_separation = 10

static const unsigned int	def_nplanes_hit_pattern = 4

static const unsigned int	def_nplanes_hit_pretrig = 2

static const unsigned int	def_pid_thresh_pretrig = 2

static const unsigned int	def_tmb_l1a_window_size = 7

Detailed Description

This class simulates the functionality of the cathode LCT card. It is run by the MotherBoard and returns up to two CathodeLCTs. It can be run either in a test mode, where it is passed arrays of halfstrip times, or in normal mode where it determines the time and comparator information from the comparator digis.

Updates for high pileup running by Vadim Khotilovich (TAMU), December 2012

Updates for integrated local trigger with GEMs by Sven Dildick (TAMU) and Tao Huang (TAMU), April 2015

Removing usage of outdated class CSCTriggerGeometry by Sven Dildick (TAMU)

Definition at line 24 of file CSCUpgradeCathodeLCTProcessor.h.

Constructor & Destructor Documentation

◆ CSCUpgradeCathodeLCTProcessor()

CSCUpgradeCathodeLCTProcessor::CSCUpgradeCathodeLCTProcessor	(	unsigned	endcap,
		unsigned	station,
		unsigned	sector,
		unsigned	subsector,
		unsigned	chamber,
		const edm::ParameterSet &	conf
	)

Normal constructor.

Definition at line 5 of file CSCUpgradeCathodeLCTProcessor.cc.

References clct_state_machine_zone_, CSCBaseboard::clctParams_, edm::ParameterSet::getParameter(), pretrig_trig_zone_, CSCBaseboard::runPhase2_, and use_dead_time_zoning_.

     : CSCCathodeLCTProcessor(endcap, station, sector, subsector, chamber, conf) {
   if (!runPhase2_)
     edm::LogError("CSCUpgradeCathodeLCTProcessor|ConfigError")
         << "+++ Upgrade CSCUpgradeCathodeLCTProcessor constructed while runPhase2_ is not set! +++\n";
 
   // use of localized dead-time zones
   use_dead_time_zoning_ = clctParams_.getParameter<bool>("useDeadTimeZoning");
   clct_state_machine_zone_ = clctParams_.getParameter<unsigned int>("clctStateMachineZone");
 
   // how far away may trigger happen from pretrigger
   pretrig_trig_zone_ = clctParams_.getParameter<unsigned int>("clctPretriggerTriggerZone");
 }

Member Function Documentation

◆ findLCTs()

std::vector< CSCCLCTDigi > CSCUpgradeCathodeLCTProcessor::findLCTs ( const std::vector< int > halfstrip[CSCConstants::NUM_LAYERS][CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER] )

overrideprivatevirtual

Reimplemented from CSCCathodeLCTProcessor.

Definition at line 106 of file CSCUpgradeCathodeLCTProcessor.cc.

                                                                                                           {
   // run the original algorithm in case we do not use dead time zoning
   if (runPhase2_ and !use_dead_time_zoning_) {
     return CSCCathodeLCTProcessor::findLCTs(halfstrip);
   }
 
   std::vector<CSCCLCTDigi> lctList;
 
   // initialize the ispretrig_ before doing pretriggering
   clearPreTriggers();
 
   if (infoV > 1)
     dumpDigis(halfstrip);
 
   // keeps dead-time zones around key halfstrips of triggered CLCTs
   for (int i = 0; i < CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER; i++) {
     for (int j = 0; j < CSCConstants::MAX_CLCT_TBINS; j++) {
       busyMap_[i][j] = false;
     }
   }
 
   // Fire half-strip one-shots for hit_persist bx's (4 bx's by default).
   pulseExtension(halfstrip);
 
   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.
   // Do search in every BX
   while (start_bx < stop_bx) {
     // temp CLCT objects
     CSCCLCTDigi tempBestCLCT;
     CSCCLCTDigi tempSecondCLCT;
 
     // All half-strip pattern envelopes are evaluated simultaneously, on every clock cycle.
     int first_bx = 999;
 
     // Check for a pre-trigger. If so, find the first BX when the pre-trigger occurred
     bool pre_trig = CSCUpgradeCathodeLCTProcessor::preTrigger(start_bx, first_bx);
 
     // If any of half-strip envelopes has enough layers hit in it, TMB
     // will pre-trigger.
     if (pre_trig) {
       if (infoV > 1)
         LogTrace("CSCUpgradeCathodeLCTProcessor")
             << "..... pretrigger at bx = " << first_bx << "; waiting drift delay .....";
 
       // TMB latches LCTs drift_delay clocks after pretrigger.
       int latch_bx = first_bx + drift_delay;
 
       // temporary container to keep track of the hits in the CLCT
       std::map<int, std::map<int, CSCCLCTDigi::ComparatorContainer> > hits_in_patterns;
       hits_in_patterns.clear();
 
       // We check if there is at least one key half strip for which at least
       // one pattern id has at least the minimum number of hits
       bool hits_in_time = patternFinding(latch_bx, hits_in_patterns);
       if (infoV > 1) {
         if (hits_in_time) {
           for (int hstrip = stagger[CSCConstants::KEY_CLCT_LAYER - 1]; hstrip < numHalfStrips_; hstrip++) {
             if (nhits[hstrip] > 0) {
               LogTrace("CSCUpgradeCathodeLCTProcessor")
                   << " bx = " << std::setw(2) << latch_bx << " --->"
                   << " halfstrip = " << std::setw(3) << hstrip << " best pid = " << std::setw(2) << best_pid[hstrip]
                   << " nhits = " << nhits[hstrip];
             }
           }
         }
       }
 
       // Quality for sorting.
       int quality[CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER];
       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;
       }
 
       bool pretrig_zone[CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER];
 
       // Calculate quality from pattern id and number of hits, and
       // simultaneously select best-quality CLCT.
       if (hits_in_time) {
         // first, mark half-strip zones around pretriggers
         // that happened at the current first_bx
         markPreTriggerZone(pretrig_zone);
 
         for (int hstrip = stagger[CSCConstants::KEY_CLCT_LAYER - 1]; hstrip < numHalfStrips_; hstrip++) {
           /* The bend-direction bit pid[0] is ignored (left and right bends have equal quality).
            This works both for the Run-2 patterns
            - PID 2,3: 2 & 14 == 2, 3 & 14 == 2
            - PID 4,5: 4 & 14 == 4, 3 & 14 == 4
            - PID 6,7: 6 & 14 == 6, 3 & 14 == 6
            - PID 8,9: 8 & 14 == 8, 3 & 14 == 8
            - PID 10: 10 & 14 == 10
            It also works for the Run-3 patterns:
            - PID 0,1: 0 & 14 == 0, 1 & 14 == 0
            - PID 2,3: 2 & 14 == 2, 3 & 14 == 2
            - PID  4:  4 & 14 == 4
           */
           quality[hstrip] = (best_pid[hstrip] & 14) | (nhits[hstrip] << 5);
           // do not consider halfstrips:
           // - out of pretrigger-trigger zones
           // - in busy zones from previous trigger
           if (quality[hstrip] > best_quality[0] && pretrig_zone[hstrip] && !busyMap_[hstrip][first_bx]) {
             best_halfstrip[0] = hstrip;
             best_quality[0] = quality[hstrip];
             // temporary alias
             const int best_hs(best_halfstrip[0]);
             const int best_pat(best_pid[best_hs]);
             // construct a CLCT if the trigger condition has been met
             if (best_hs >= 0 && nhits[best_hs] >= nplanes_hit_pattern) {
               // overwrite the current best CLCT
               tempBestCLCT = constructCLCT(first_bx, best_hs, hits_in_patterns[best_hs][best_pat]);
             }
           }
         }
       }
 
       // If 1st best CLCT is found, look for the 2nd best.
       if (best_halfstrip[0] >= 0) {
         // Get the half-strip of the best CLCT in this BX that was put into the list.
         // You do need to re-add the any stagger, because the busy keys are based on
         // the pulse array which takes into account strip stagger!!!
         const unsigned halfStripBestCLCT(tempBestCLCT.getKeyStrip() + stagger[CSCConstants::KEY_CLCT_LAYER - 1]);
 
         // 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);
         markBusyKeys(halfStripBestCLCT, best_pid[halfStripBestCLCT], quality);
 
         for (int hstrip = stagger[CSCConstants::KEY_CLCT_LAYER - 1]; hstrip < numHalfStrips_; hstrip++) {
           // we don't have to recalculate the quality for each half-strip
           if (quality[hstrip] > best_quality[1] && pretrig_zone[hstrip] && !busyMap_[hstrip][first_bx]) {
             best_halfstrip[1] = hstrip;
             best_quality[1] = quality[hstrip];
             // temporary alias
             const int best_hs(best_halfstrip[1]);
             const int best_pat(best_pid[best_hs]);
             // construct a CLCT if the trigger condition has been met
             if (best_hs >= 0 && nhits[best_hs] >= nplanes_hit_pattern) {
               // overwrite the current second best CLCT
               tempSecondCLCT = constructCLCT(first_bx, best_hs, hits_in_patterns[best_hs][best_pat]);
             }
           }
         }
 
         // Sort bestCLCT and secondALCT by quality
         // if qualities are the same, sort by run-2 or run-3 pattern
         // if qualities and patterns are the same, sort by half strip number
         bool changeOrder = false;
 
         unsigned qualityBest = 0, qualitySecond = 0;
         unsigned patternBest = 0, patternSecond = 0;
         unsigned halfStripBest = 0, halfStripSecond = 0;
 
         if (tempBestCLCT.isValid() and tempSecondCLCT.isValid()) {
           qualityBest = tempBestCLCT.getQuality();
           qualitySecond = tempSecondCLCT.getQuality();
           if (!run3_) {
             patternBest = tempBestCLCT.getPattern();
             patternSecond = tempSecondCLCT.getPattern();
           } else {
             patternBest = tempBestCLCT.getRun3Pattern();
             patternSecond = tempSecondCLCT.getRun3Pattern();
           }
           halfStripBest = tempBestCLCT.getKeyStrip();
           halfStripSecond = tempSecondCLCT.getKeyStrip();
 
           if (qualitySecond > qualityBest)
             changeOrder = true;
           else if ((qualitySecond == qualityBest) and (int(patternSecond / 2) > int(patternBest / 2)))
             changeOrder = true;
           else if ((qualitySecond == qualityBest) and (int(patternSecond / 2) == int(patternBest / 2)) and
                    (halfStripSecond < halfStripBest))
             changeOrder = true;
         }
 
         CSCCLCTDigi tempCLCT;
         if (changeOrder) {
           tempCLCT = tempBestCLCT;
           tempBestCLCT = tempSecondCLCT;
           tempSecondCLCT = tempCLCT;
         }
 
         // add the CLCTs to the collection
         if (tempBestCLCT.isValid()) {
           lctList.push_back(tempBestCLCT);
         }
         if (tempSecondCLCT.isValid()) {
           lctList.push_back(tempSecondCLCT);
         }
       }  //find CLCT, end of best_halfstrip[0] >= 0
     }    //pre_trig
     // The pattern finder runs continuously, so another pre-trigger
     // could occur already at the next bx.
     start_bx = first_bx + 1;
   }
   return lctList;
 }  // findLCTs -- Phase2 version.

◆ markBusyZone()

void CSCUpgradeCathodeLCTProcessor::markBusyZone ( const int bx )

private

Definition at line 337 of file CSCUpgradeCathodeLCTProcessor.cc.

References busyMap_, simKBmtfDigis_cfi::bx, clct_state_machine_zone_, CSCBaseboard::infoV, CSCCathodeLCTProcessor::ispretrig_, CSCConstants::KEY_CLCT_LAYER, LogTrace, CSCCathodeLCTProcessor::numHalfStrips_, and CSCCathodeLCTProcessor::stagger.

Referenced by preTrigger().

                                                              {
   for (int hstrip = stagger[CSCConstants::KEY_CLCT_LAYER - 1]; hstrip < numHalfStrips_; hstrip++) {
     // check if this halfstrip has a pretrigger
     if (ispretrig_[hstrip]) {
       // only fixed localized dead time zone is implemented in firmware
       int min_hstrip = hstrip - clct_state_machine_zone_;
       int max_hstrip = hstrip + clct_state_machine_zone_;
       // set the minimum strip
       if (min_hstrip < stagger[CSCConstants::KEY_CLCT_LAYER - 1])
         min_hstrip = stagger[CSCConstants::KEY_CLCT_LAYER - 1];
       // set the maximum strip
       if (max_hstrip >= numHalfStrips_)
         max_hstrip = numHalfStrips_ - 1;
       // mask the busy half-strips for 1 BX after the pretrigger
       for (int hs = min_hstrip; hs <= max_hstrip; hs++)
         busyMap_[hs][bx + 1] = true;
       if (infoV > 1)
         LogTrace("CSCUpgradeCathodeLCTProcessor")
             << " marked zone around pretriggerred halfstrip " << hstrip << " as dead zone for pretriggering at bx"
             << bx + 1 << " halfstrip: [" << min_hstrip << "," << max_hstrip << "]";
     }
   }
 }

◆ markPreTriggerZone()

void CSCUpgradeCathodeLCTProcessor::markPreTriggerZone ( bool pretrig_zone[CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER] ) const

private

Definition at line 310 of file CSCUpgradeCathodeLCTProcessor.cc.

References CSCBaseboard::infoV, CSCCathodeLCTProcessor::ispretrig_, LogTrace, CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER, and pretrig_trig_zone_.

Referenced by findLCTs().

                                                                            {
   // first reset the pretrigger zone (no pretriggers anywhere in this BX
   for (int hstrip = 0; hstrip < CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER; hstrip++) {
     pretrig_zone[hstrip] = false;
   }
   // then set the pretrigger zone according to the ispretrig_ array
   for (int hstrip = 0; hstrip < CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER; hstrip++) {
     if (ispretrig_[hstrip]) {
       int min_hs = hstrip - pretrig_trig_zone_;
       int max_hs = hstrip + pretrig_trig_zone_;
       // set the minimum strip
       if (min_hs < 0)
         min_hs = 0;
       // set the maximum strip
       if (max_hs > CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER - 1)
         max_hs = CSCConstants::MAX_NUM_HALF_STRIPS_RUN2_TRIGGER - 1;
       // mark the pre-trigger zone
       for (int hs = min_hs; hs <= max_hs; hs++)
         pretrig_zone[hs] = true;
       if (infoV > 1)
         LogTrace("CSCUpgradeCathodeLCTProcessor")
             << " marked pretrigger halfstrip zone [" << min_hs << "," << max_hs << "]";
     }
   }
 }

◆ preTrigger()

bool CSCUpgradeCathodeLCTProcessor::preTrigger	(	const int	start_bx,
		int &	first_bx
	)

overrideprivatevirtual

Reimplemented from CSCCathodeLCTProcessor.

Definition at line 29 of file CSCUpgradeCathodeLCTProcessor.cc.

Referenced by findLCTs().

                                                                                 {
   if (runPhase2_ and !use_dead_time_zoning_) {
     return CSCCathodeLCTProcessor::preTrigger(start_bx, first_bx);
   }
 
   if (infoV > 1)
     LogTrace("CSCUpgradeCathodeLCTProcessor")
         << "....................PreTrigger, Phase2 version with localized dead time zone...........................";
 
   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.
     std::map<int, std::map<int, CSCCLCTDigi::ComparatorContainer> > hits_in_patterns;
     hits_in_patterns.clear();
 
     bool hits_in_time = patternFinding(bx_time, hits_in_patterns);
     if (hits_in_time) {
       for (int hstrip = stagger[CSCConstants::KEY_CLCT_LAYER - 1]; hstrip < numHalfStrips_; hstrip++) {
         if (infoV > 1) {
           if (nhits[hstrip] > 0) {
             LogTrace("CSCUpgradeCathodeLCTProcessor")
                 << " bx = " << std::setw(2) << bx_time << " --->"
                 << " halfstrip = " << std::setw(3) << hstrip << " best pid = " << std::setw(2) << best_pid[hstrip]
                 << " nhits = " << nhits[hstrip];
           }
         }
         // note that ispretrig_ is initialized in findLCT function
         if (nhits[hstrip] >= nplanes_hit_pretrig && best_pid[hstrip] >= pid_thresh_pretrig &&
             !busyMap_[hstrip][bx_time]) {
           pre_trig = true;
           ispretrig_[hstrip] = true;
 
           // write each pre-trigger to output
           nPreTriggers++;
           thePreTriggerDigis.push_back(constructPreCLCT(bx_time, hstrip, nPreTriggers));
         }
         // busy zone, keep pretriggering, ignore this
         else if (nhits[hstrip] >= nplanes_hit_pretrig && best_pid[hstrip] >= pid_thresh_pretrig) {
           ispretrig_[hstrip] = true;
           if (infoV > 1)
             LogTrace("CSCUpgradeCathodeLCTProcessor")
                 << " halfstrip " << std::setw(3) << hstrip << " in dead zone and is pretriggerred";
         }
         // no pretrigger on this halfstrip, release dead zone
         else if (nhits[hstrip] < nplanes_hit_pretrig || best_pid[hstrip] < pid_thresh_pretrig) {
           ispretrig_[hstrip] = false;
         }
       }  // find all pretriggers
 
       // update dead zone
       markBusyZone(bx_time);
 
       if (pre_trig) {
         first_bx = bx_time;  // bx at time of pretrigger
         return true;
       }
     } else {
       // no pattern found, remove all dead zone
       clearPreTriggers();
     }
   }  // end loop over bx times
 
   if (infoV > 1)
     LogTrace("CSCUpgradeCathodeLCTProcessor") << "no pretrigger, returning \n";
   first_bx = fifo_tbins;
   return false;
 }  // preTrigger -- Phase2 version.