tracking::reco::channelmap Namespace Reference

Central definition of the tracker silicon-strip channel mapping. More...

Functions
constexpr int16_t	pchannel (uint8_t apv_id, uint8_t channel)
	Convert an (APV id, APV channel) pair into the physical strip number (pchannel) within a hybrid, in [0, kChannelsPerHybrid).
constexpr void	apvChannelFromPchannel (int16_t pchannel, uint8_t &apv_id, uint8_t &channel)
	Inverse of pchannel(): recover the (APV id, APV channel) pair from a physical strip number.
constexpr int	stripId (int16_t pchannel, int n_strips, int first_strip, bool reversed)
	Map a physical strip number (pchannel) onto a sensor strip index using a DAQ-map transform: an optional readout reversal plus a per-sensor offset.
std::string	channelKey (uint8_t feb, uint8_t hybrid, uint8_t apv, uint8_t channel)
	Build the per-channel pedestal-map key "feb:hybrid:apv:channel".
constexpr uint32_t	channelId (uint8_t feb, uint8_t hybrid, uint8_t apv, uint8_t channel)
	Pack the full electronics address (feb, hybrid, apv, channel) into a single 32-bit id, used as the row key of the pedestal conditions table.
bool	parseChannelKey (const std::string &key, uint8_t &feb, uint8_t &hybrid, uint8_t &apv, uint8_t &channel)
	Parse a "feb:hybrid:apv:channel" key (as produced by channelKey()) back into its electronics fields.
constexpr uint32_t	groupKey (uint8_t feb, uint8_t hybrid, int16_t pchannel)
	Pack (feb, hybrid, pchannel) into a single 32-bit waveform-grouping key.
constexpr int16_t	pchannelFromGroupKey (uint32_t key)
	Extract the pchannel back out of a key produced by groupKey().

Variables
constexpr int	K_CHANNELS_PER_APV = 128
	Number of readout channels per APV25 chip.
constexpr int	K_APVS_PER_HYBRID = 5
	Number of APV25 chips per hybrid.
constexpr int	K_CHANNELS_PER_HYBRID
	Number of physical strips per hybrid (kApvsPerHybrid * kChannelsPerApv).
constexpr int	K_SAMPLES_PER_APV_TRIGGER = 3
	Number of ADC samples the APV25 reads out per channel per trigger.

Detailed Description

Central definition of the tracker silicon-strip channel mapping.

Every electronics-id <-> physical-strip conversion (and the keys used to group/lookup channels) lives here so the layout only has to change in one place. All functions are header-only constexpr/inline helpers; there is no per-instance state.

Function Documentation

apvChannelFromPchannel()

void tracking::reco::channelmap::apvChannelFromPchannel ( int16_t pchannel, uint8_t & apv_id, uint8_t & channel )

inlineconstexpr

Inverse of pchannel(): recover the (APV id, APV channel) pair from a physical strip number.

Needed because SiStripWaveform stores only the pchannel, but the pedestal table is keyed by the full electronics address.

Round-trips exactly with pchannel() for all valid (apv, channel): apvChannelFromPchannel(pchannel(a, c), a', c') gives a' == a, c' == c.

Definition at line 52 of file SiStripChannelMap.h.

                                                               {
  const int x = (K_CHANNELS_PER_HYBRID - 1) - pchannel;
  apv_id = static_cast<uint8_t>(x / K_CHANNELS_PER_APV);
  channel =
      static_cast<uint8_t>((K_CHANNELS_PER_APV - 1) - (x % K_CHANNELS_PER_APV));
}

References K_CHANNELS_PER_APV, K_CHANNELS_PER_HYBRID, and pchannel().

Referenced by tracking::reco::SiStripWaveformFitProcessor::produce().

channelId()

uint32_t tracking::reco::channelmap::channelId ( uint8_t feb, uint8_t hybrid, uint8_t apv, uint8_t channel )

inlineconstexpr

Pack the full electronics address (feb, hybrid, apv, channel) into a single 32-bit id, used as the row key of the pedestal conditions table.

Definition at line 85 of file SiStripChannelMap.h.

                                                     {
  return (static_cast<uint32_t>(feb) << 24) |
         (static_cast<uint32_t>(hybrid) << 16) |
         (static_cast<uint32_t>(apv) << 8) | static_cast<uint32_t>(channel);
}

Referenced by tracking::reco::TrackerPedestals::add(), and tracking::reco::TrackerPedestals::find().

channelKey()

std::string tracking::reco::channelmap::channelKey ( uint8_t feb, uint8_t hybrid, uint8_t apv, uint8_t channel )

inline

Build the per-channel pedestal-map key "feb:hybrid:apv:channel".

Definition at line 77 of file SiStripChannelMap.h.

                                               {
  return std::to_string(feb) + ":" + std::to_string(hybrid) + ":" +
         std::to_string(apv) + ":" + std::to_string(channel);
}

Referenced by tracking::reco::PedestalCalculator::analyze(), and tracking::reco::PedestalSubtractor::produce().

groupKey()

uint32_t tracking::reco::channelmap::groupKey ( uint8_t feb, uint8_t hybrid, int16_t pchannel )

inlineconstexpr

Pack (feb, hybrid, pchannel) into a single 32-bit waveform-grouping key.

Definition at line 107 of file SiStripChannelMap.h.

                                                     {
  return (static_cast<uint32_t>(feb) << 24) |
         (static_cast<uint32_t>(hybrid) << 16) |
         static_cast<uint32_t>(static_cast<uint16_t>(pchannel));
}

References pchannel().

Referenced by tracking::reco::SiStripWaveformBuilder::produce().

parseChannelKey()

bool tracking::reco::channelmap::parseChannelKey ( const std::string & key, uint8_t & feb, uint8_t & hybrid, uint8_t & apv, uint8_t & channel )

inline

Parse a "feb:hybrid:apv:channel" key (as produced by channelKey()) back into its electronics fields.

Returns false if the string is malformed.

Definition at line 94 of file SiStripChannelMap.h.

                                                                             {
  unsigned f, h, a, c;
  if (std::sscanf(key.c_str(), "%u:%u:%u:%u", &f, &h, &a, &c) != 4)
    return false;
  feb = static_cast<uint8_t>(f);
  hybrid = static_cast<uint8_t>(h);
  apv = static_cast<uint8_t>(a);
  channel = static_cast<uint8_t>(c);
  return true;
}

pchannel()

int16_t tracking::reco::channelmap::pchannel ( uint8_t apv_id, uint8_t channel )

inlineconstexpr

Convert an (APV id, APV channel) pair into the physical strip number (pchannel) within a hybrid, in [0, kChannelsPerHybrid).

The APV readout order is reversed relative to the physical strip order, and the APVs are laid out back-to-front along the hybrid, hence the double reversal.

Definition at line 38 of file SiStripChannelMap.h.

                                                                   {
  return static_cast<int16_t>(
      (K_CHANNELS_PER_HYBRID - 1) -
      (apv_id * K_CHANNELS_PER_APV + (K_CHANNELS_PER_APV - 1) - channel));
}

References K_CHANNELS_PER_APV, and K_CHANNELS_PER_HYBRID.

Referenced by apvChannelFromPchannel(), groupKey(), tracking::reco::SiStripWaveformBuilder::produce(), and stripId().

pchannelFromGroupKey()

int16_t tracking::reco::channelmap::pchannelFromGroupKey ( uint32_t key )

inlineconstexpr

Extract the pchannel back out of a key produced by groupKey().

Definition at line 115 of file SiStripChannelMap.h.

                                                            {
  return static_cast<int16_t>(key & 0xFFFF);
}

Referenced by tracking::reco::SiStripWaveformBuilder::produce().

stripId()

int tracking::reco::channelmap::stripId ( int16_t pchannel, int n_strips, int first_strip, bool reversed )

inlineconstexpr

Map a physical strip number (pchannel) onto a sensor strip index using a DAQ-map transform: an optional readout reversal plus a per-sensor offset.

Parameters

pchannel	physical strip within the hybrid, [0, kChannelsPerHybrid).
n_strips	number of bonded strips on the sensor.
first_strip	sensor strip index that pchannel 0 (or the reversed end) maps to.
reversed	true if the hybrid reads the sensor in descending order.

Definition at line 70 of file SiStripChannelMap.h.

                                            {
  return reversed ? first_strip + n_strips - 1 - pchannel
                  : first_strip + pchannel;
}

References pchannel().

Referenced by tracking::reco::SiStripWaveformFitProcessor::produce().

Variable Documentation

K_APVS_PER_HYBRID

int tracking::reco::channelmap::K_APVS_PER_HYBRID = 5

inlineconstexpr

Number of APV25 chips per hybrid.

Definition at line 23 of file SiStripChannelMap.h.

K_CHANNELS_PER_APV

int tracking::reco::channelmap::K_CHANNELS_PER_APV = 128

inlineconstexpr

Number of readout channels per APV25 chip.

Definition at line 21 of file SiStripChannelMap.h.

Referenced by apvChannelFromPchannel(), and pchannel().

K_CHANNELS_PER_HYBRID

int tracking::reco::channelmap::K_CHANNELS_PER_HYBRID

inlineconstexpr

Initial value:

=
    K_APVS_PER_HYBRID * K_CHANNELS_PER_APV

Number of physical strips per hybrid (kApvsPerHybrid * kChannelsPerApv).

Definition at line 25 of file SiStripChannelMap.h.

Referenced by apvChannelFromPchannel(), and pchannel().

K_SAMPLES_PER_APV_TRIGGER

int tracking::reco::channelmap::K_SAMPLES_PER_APV_TRIGGER = 3

inlineconstexpr

Number of ADC samples the APV25 reads out per channel per trigger.

Definition at line 28 of file SiStripChannelMap.h.

Referenced by tracking::reco::PedestalCalculator::analyze(), tracking::reco::PedestalSubtractor::produce(), tracking::reco::SiStripWaveformBuilder::produce(), and tracking::reco::PedestalCalculator::writePedestalsJson().