Contains the core logic for the Hgcroc trigger calculations. More...

#include <HgcrocTriggerCalculations.h>

Public Member Functions
	HgcrocTriggerCalculations (const conditions::IntegerTableCondition &ict)
	Construct the chip trigger calculator.

void	addDigi (unsigned int id, unsigned int tid, int adc, int tot)
	Determine the linear charge for the given channel, using the calibration information, and add it to the map of trigger channel IDs to linear charge measurements.

void	compressDigis (int cells_per_trig)
	Convert the linear charges to compressed charges, with a division depending on the number of cells summed by HGCROC.

const std::map< unsigned int, uint8_t > &	compressedEnergies () const
	Access the map of trigger ids to compressed energies.

Static Public Member Functions
static unsigned int	singleChannelCharge (int adc, int tot, int adc_ped, int adc_thresh, int tot_ped, int tot_thresh, int tot_gain)
	Calculates the linear trigger charge for a single precision channel (before 2x2 or 3x3 summing)

Private Attributes
HgcrocTriggerConditions	conditions_
	The conditions to be used.

std::map< unsigned int, unsigned int >	linearCharge_
	A map of trigger channel id to linear charge.

std::map< unsigned int, uint8_t >	compressedCharge_
	A map of trigger channel id to compressed charge.

Detailed Description

Contains the core logic for the Hgcroc trigger calculations.

This class is meant to be created once per event along with the conditions for the chip. These chip conditions are wrapped in an HgcrocTriggerConditions class for easier access. These chip conditions may change from event-to-event, so it is best to allow for this object to change from event-to-event.

Definition at line 109 of file HgcrocTriggerCalculations.h.

Constructor & Destructor Documentation

◆ HgcrocTriggerCalculations()

ldmx::HgcrocTriggerCalculations::HgcrocTriggerCalculations ( const conditions::IntegerTableCondition & ict )

Construct the chip trigger calculator.

Here we pass the table of chip conditions that is used to emulate the chip's behavior for all of the different channel IDs.

We also use this opportunity to double check that the column indices in HgcrocTriggerConditions match the column indices imported from the input table.

Parameters

[in] ict table of chip conditions

Definition at line 56 of file HgcrocTriggerCalculations.cxx.

58 : conditions_{ict, true} {}

ldmx::HgcrocTriggerCalculations::conditions_

HgcrocTriggerConditions conditions_

The conditions to be used.

Definition HgcrocTriggerCalculations.h:188

Member Function Documentation

◆ addDigi()

void ldmx::HgcrocTriggerCalculations::addDigi	(	unsigned int	id,
		unsigned int	tid,
		int	adc,
		int	tot
	)

Determine the linear charge for the given channel, using the calibration information, and add it to the map of trigger channel IDs to linear charge measurements.

See also: singleChannelCharge for how the precision channel measurement is converted to a linear trig-digi charge

Parameters

id	Precision channel id (used to lookup in the conditions table)
tid	Trigger channel id
adc	ADC measurement of precision channel if not TOT complete
tot	TOT measurement of precision channel if TOT is complete

Definition at line 60 of file HgcrocTriggerCalculations.cxx.

                                                          {
  unsigned int charge = singleChannelCharge(
      adc, tot, conditions_.adcPedestal(id), conditions_.adcThreshold(id),
      conditions_.totPedestal(id), conditions_.totThreshold(id),
      conditions_.totGain(id));
  if (charge > 0) {
    std::map<unsigned int, unsigned int>::iterator ic = linearCharge_.find(tid);
    if (ic == linearCharge_.end())
      linearCharge_[tid] = charge;
    else
      ic->second += charge;
  }
}

References ldmx::HgcrocTriggerConditions::adcPedestal(), ldmx::HgcrocTriggerConditions::adcThreshold(), conditions_, linearCharge_, singleChannelCharge(), ldmx::HgcrocTriggerConditions::totGain(), ldmx::HgcrocTriggerConditions::totPedestal(), and ldmx::HgcrocTriggerConditions::totThreshold().

Referenced by ecal::EcalTrigPrimDigiProducer::produce(), and hcal::HcalTrigPrimDigiProducer::produce().

◆ compressDigis()

void ldmx::HgcrocTriggerCalculations::compressDigis ( int cells_per_trig )

Convert the linear charges to compressed charges, with a division depending on the number of cells summed by HGCROC.

Fills the map of trigger channel IDs to compressed charge measurements. Some of the lowest order bits are dropped during compression in order to effectively reach the necessary dynamic range. The number of these bits that are dropped depends on the number of cells in each trigger grouping.

9 --> drop 8 lowest order bits --> multiply unpacked charge by 8 to get full amount
4 --> drop 4 lowest order bits --> mutliply unpacked charge by 4 to get full amount

@raises Exception if the input cells_per_trig is not 4 or 9.

Parameters

cells_per_trig Valid values are 4 or 9

Definition at line 75 of file HgcrocTriggerCalculations.cxx.

                                                                {
  int shift;
  if (cells_per_trig == 4)
    shift = 1;
  else if (cells_per_trig == 9)
    shift = 3;
  else {
    EXCEPTION_RAISE("HgcrocTriggerException",
                    "Invalid number of precision cells per trigger cell: " +
                        std::to_string(cells_per_trig));
  }
 
  for (auto ilinear : linearCharge_) {
    unsigned int lcharge = ilinear.second;
    lcharge = lcharge >> shift;
    uint8_t ccharge = ldmx::HgcrocTrigDigi::linear2Compressed(lcharge);
    compressedCharge_[ilinear.first] = ccharge;
  }
}

References compressedCharge_, ldmx::HgcrocTrigDigi::linear2Compressed(), and linearCharge_.

Referenced by ecal::EcalTrigPrimDigiProducer::produce(), and hcal::HcalTrigPrimDigiProducer::produce().

◆ compressedEnergies()

const std::map< unsigned int, uint8_t > & ldmx::HgcrocTriggerCalculations::compressedEnergies ( ) const

inline

Access the map of trigger ids to compressed energies.

Returns: const reference to the map of trigger channel ID to compressed charge measurements

Definition at line 182 of file HgcrocTriggerCalculations.h.

                                                                  {
    return compressedCharge_;
  }

References compressedCharge_.

Referenced by ecal::EcalTrigPrimDigiProducer::produce(), and hcal::HcalTrigPrimDigiProducer::produce().

◆ singleChannelCharge()

unsigned int ldmx::HgcrocTriggerCalculations::singleChannelCharge	(	int	adc,
		int	tot,
		int	adc_ped,
		int	adc_thresh,
		int	tot_ped,
		int	tot_thresh,
		int	tot_gain
	)

static

Calculates the linear trigger charge for a single precision channel (before 2x2 or 3x3 summing)

Parameters

adc	ADC measurement for the channel
tot	TOT measurement for the channel or zero if no TOT
adc_ped	Trigger pedestal to subtract (8 bits, per channel)
adc_thresh	ADC threshold for noise-suppression in the trigger path (5 bits, global for ROC)
tot_ped	TOT pedestal (7 bits, group-of-nine)
tot_thresh	TOT threshold, use this fixed value as "TOT" if the TOT is below this value (8 bits, group-of-nine)
tot_gain	TOT to charge multiplicative factor (5 bits, integer math, global for ROC)

Returns: linear trigger charge from a single precision channel

Definition at line 34 of file HgcrocTriggerCalculations.cxx.

                  {
  unsigned int charge_adc = 0;
 
  if (adc > (adc_ped + adc_thresh))
    charge_adc = adc - adc_ped;  // otherwise zero
 
  unsigned int eff_tot{0};
  if (tot > tot_thresh && tot > tot_ped)
    eff_tot = tot - tot_ped;
  else
    eff_tot = tot_thresh - tot_ped;
 
  unsigned int charge_tot{0};
  charge_tot = eff_tot * tot_gain;
 
  unsigned int charge_final = (tot != 0) ? (charge_tot) : (charge_adc);
 
  return charge_final;
}