SiStripRawToDigiUnpacker.cc

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#include <iostream>
#include <sstream>
#include <iomanip>
#include <ext/algorithm>

#include <fmt/format.h>

#include "CondFormats/SiStripObjects/interface/SiStripFedCabling.h"
#include "DataFormats/Common/interface/DetSet.h"
#include "DataFormats/FEDRawData/interface/FEDHeader.h"
#include "DataFormats/FEDRawData/interface/FEDNumbering.h"
#include "DataFormats/FEDRawData/interface/FEDRawDataCollection.h"
#include "DataFormats/FEDRawData/interface/FEDTrailer.h"
#include "DataFormats/SiStripCommon/interface/SiStripConstants.h"
#include "DataFormats/SiStripCommon/interface/SiStripEventSummary.h"
#include "DataFormats/SiStripDigi/interface/SiStripDigi.h"
#include "DataFormats/SiStripDigi/interface/SiStripRawDigi.h"
#include "EventFilter/SiStripRawToDigi/interface/TFHeaderDescription.h"
#include "FWCore/MessageLogger/interface/MessageLogger.h"
#include "FWCore/Utilities/interface/Exception.h"
#include "FWCore/Utilities/interface/RunningAverage.h"

#include "SiStripRawToDigiUnpacker.h"

namespace sistrip {

  RawToDigiUnpacker::RawToDigiUnpacker(int16_t appended_bytes,
                                       int16_t fed_buffer_dump_freq,
                                       int16_t fed_event_dump_freq,
                                       int16_t trigger_fed_id,
                                       bool using_fed_key,
                                       bool unpack_bad_channels,
                                       bool mark_missing_feds,
                                       const uint32_t errorThreshold)
      : headerBytes_(appended_bytes),
        fedBufferDumpFreq_(fed_buffer_dump_freq),
        fedEventDumpFreq_(fed_event_dump_freq),
        triggerFedId_(trigger_fed_id),
        useFedKey_(using_fed_key),
        unpackBadChannels_(unpack_bad_channels),
        markMissingFeds_(mark_missing_feds),
        event_(0),
        once_(true),
        first_(true),
        useDaqRegister_(false),
        quiet_(true),
        extractCm_(false),
        doFullCorruptBufferChecks_(false),
        doAPVEmulatorCheck_(true),
        errorThreshold_(errorThreshold),
        warnings_(sistrip::mlRawToDigi_, "[sistrip::RawToDigiUnpacker::createDigis]", edm::isDebugEnabled()) {
    if (edm::isDebugEnabled()) {
      LogTrace("SiStripRawToDigi") << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
                                   << " Constructing object...";
    }
    if (unpackBadChannels_) {
      edm::LogWarning("SiStripRawToDigi")
          << "Warning: Unpacking of bad channels enabled. Only enable this if you know what you are doing. "
          << std::endl;
    }
  }

  RawToDigiUnpacker::~RawToDigiUnpacker() {
    if (edm::isDebugEnabled()) {
      LogTrace("SiStripRawToDigi") << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
                                   << " Destructing object...";
    }
  }

  namespace {

    edm::RunningAverage localRA(10000);

    void maskFED(DetIdCollection& maskedModules, SiStripFedCabling::ConnsConstIterRange fedConnections) {
      maskedModules.reserve(maskedModules.size() + fedConnections.size());
      for (const auto& conn : fedConnections) {
        if (conn.detId() && (conn.detId() != sistrip::invalid32_)) {
          maskedModules.push_back(conn.detId());  //@@ Possible multiple entries (ok for Giovanni)
        }
      }
    }
  }  // namespace

  void RawToDigiUnpacker::createDigis(const SiStripFedCabling& cabling,
                                      const FEDRawDataCollection& buffers,
                                      SiStripEventSummary& summary,
                                      RawDigis& scope_mode,
                                      RawDigis& virgin_raw,
                                      RawDigis& proc_raw,
                                      Digis& zero_suppr,
                                      DetIdCollection& detids,
                                      RawDigis& cm_values) {
    // Clear done at the end
    assert(zs_work_digis_.empty());
    zs_work_digis_.reserve(localRA.upper());
    // Reserve space in bad module list
    detids.reserve(100);

    // Check if FEDs found in cabling map and event data
    if (cabling.fedIds().empty()) {
      warnings_.add("No FEDs found in cabling map!");
      if (edm::isDebugEnabled()) {
        // Check which FED ids have non-zero size buffers
        std::vector<uint16_t> feds;
        for (uint16_t ifed = FEDNumbering::MINSiStripFEDID; ifed < FEDNumbering::MAXSiStripFEDID; ifed++) {
          if (ifed != triggerFedId_ && buffers.FEDData(static_cast<int>(ifed)).size()) {
            feds.push_back(ifed);
          }
        }
        LogTrace("SiStripRawToDigi") << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
                                     << " Found " << feds.size() << " FED buffers with non-zero size!";
      }
    }

    // Flag for EventSummary update using DAQ register
    bool first_fed = true;

    // Retrieve FED ids from cabling map and iterate through
    std::vector<uint16_t>::const_iterator ifed = cabling.fedIds().begin();
    for (; ifed != cabling.fedIds().end(); ifed++) {
      // ignore trigger FED
      if (*ifed == triggerFedId_) {
        continue;
      }

      // Retrieve FED raw data for given FED
      const FEDRawData& input = buffers.FEDData(static_cast<int>(*ifed));

      // Some debug on FED buffer size
      if (edm::isDebugEnabled()) {
        if (first_ && input.data()) {
          std::stringstream ss;
          ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
             << " Found FED id " << std::setw(4) << std::setfill(' ') << *ifed << " in FEDRawDataCollection"
             << " with non-zero pointer 0x" << std::hex << std::setw(8) << std::setfill('0')
             << reinterpret_cast<const uint32_t*>(input.data()) << std::dec << " and size " << std::setw(5)
             << std::setfill(' ') << input.size() << " chars";
          LogTrace("SiStripRawToDigi") << ss.str();
        }
      }

      // Dump of FEDRawData to stdout
      if (edm::isDebugEnabled()) {
        if (fedBufferDumpFreq_ && !(event_ % fedBufferDumpFreq_)) {
          std::stringstream ss;
          dumpRawData(*ifed, input, ss);
          edm::LogVerbatim(sistrip::mlRawToDigi_) << ss.str();
        }
      }

      // get the cabling connections for this FED
      auto conns = cabling.fedConnections(*ifed);
      // check FEDRawData pointer, size, and more
      const auto st_buffer = preconstructCheckFEDBuffer(input);
      // construct FEDBuffer
      if (FEDBufferStatusCode::SUCCESS != st_buffer) {
        if (FEDBufferStatusCode::BUFFER_NULL == st_buffer) {
          warnings_.add("NULL pointer to FEDRawData for FED", fmt::format("id {0}", *ifed));
        } else if (!input.size()) {
          warnings_.add("FEDRawData has zero size for FED", fmt::format("id {0}", *ifed));
        } else {
          warnings_.add("Exception caught when creating FEDBuffer object for FED",
                        fmt::format("id {0}: {1}", *ifed, st_buffer));
        }
        // FED buffer is bad and should not be unpacked. Skip this FED and mark all modules as bad.
        maskFED(detids, conns);
        continue;
      }
      FEDBuffer buffer{input};
      const auto st_chan = buffer.findChannels();
      if (FEDBufferStatusCode::SUCCESS != st_chan) {
        warnings_.add("Exception caught when creating FEDBuffer object for FED",
                      fmt::format("id {0}: {1}", *ifed, st_chan));
        maskFED(detids, conns);
        continue;
      }
      buffer.setLegacyMode(legacy_);
      if ((!buffer.doChecks(true)) && (!unpackBadChannels_ || !buffer.checkNoFEOverflows())) {
        warnings_.add("Exception caught when creating FEDBuffer object for FED",
                      fmt::format("id {0}: FED Buffer check fails for FED ID {0}.", *ifed));
        maskFED(detids, conns);
        continue;
      }
      if (doFullCorruptBufferChecks_ && !buffer.doCorruptBufferChecks()) {
        warnings_.add("Exception caught when creating FEDBuffer object for FED",
                      fmt::format("id {0}: FED corrupt buffer check fails for FED ID {0}.", *ifed));
        maskFED(detids, conns);
        continue;
      }

      // Check if EventSummary ("trigger FED info") needs updating
      if (first_fed && useDaqRegister_) {
        updateEventSummary(buffer, summary);
        first_fed = false;
      }

      // Check to see if EventSummary info is set
      if (!quiet_ && !summary.isSet()) {
        warnings_.add(
            "EventSummary is not set correctly! Missing information from both \"trigger FED\" and \"DAQ registers\"!");
      }

      // Check to see if event is to be analyzed according to EventSummary
      if (!summary.valid()) {
        if (edm::isDebugEnabled()) {
          LogTrace("SiStripRawToDigi") << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
                                       << " EventSummary is not valid: skipping...";
        }
        continue;
      }

      const sistrip::FEDReadoutMode mode = buffer.readoutMode();
      const sistrip::FEDLegacyReadoutMode lmode =
          (legacy_) ? buffer.legacyReadoutMode() : sistrip::READOUT_MODE_LEGACY_INVALID;

      // Retrive run type
      const sistrip::RunType runType_ = summary.runType();
      if (runType_ == sistrip::APV_LATENCY || runType_ == sistrip::FINE_DELAY) {
        useFedKey_ = false;
      }

      // Dump of FED buffer
      if (edm::isDebugEnabled()) {
        if (fedEventDumpFreq_ && !(event_ % fedEventDumpFreq_)) {
          std::stringstream ss;
          buffer.dump(ss);
          edm::LogVerbatim(sistrip::mlRawToDigi_) << ss.str();
        }
      }

      // Iterate through FED channels, extract payload and create Digis
      std::vector<FedChannelConnection>::const_iterator iconn = conns.begin();
      for (; iconn != conns.end(); iconn++) {
        uint16_t chan = iconn->fedCh();

        // Check if fed connection is valid
        if (!iconn->isConnected()) {
          continue;
        }

        // Check DetId is valid (if to be used as key)
        if (!useFedKey_ && (!iconn->detId() || iconn->detId() == sistrip::invalid32_)) {
          continue;
        }

        // Check FED channel
        if (!buffer.channelGood(iconn->fedCh(), doAPVEmulatorCheck_)) {
          if (!unpackBadChannels_ || !(buffer.fePresent(iconn->fedCh() / FEDCH_PER_FEUNIT) &&
                                       buffer.feEnabled(iconn->fedCh() / FEDCH_PER_FEUNIT))) {
            detids.push_back(iconn->detId());  //@@ Possible multiple entries (ok for Giovanni)
            continue;
          }
        }

        // Determine whether FED key is inferred from cabling or channel loop
        const uint32_t fed_key =
            (summary.runType() == sistrip::FED_CABLING)
                ? ((*ifed & sistrip::invalid_) << 16) | (chan & sistrip::invalid_)
                : ((iconn->fedId() & sistrip::invalid_) << 16) | (iconn->fedCh() & sistrip::invalid_);

        // Determine whether DetId or FED key should be used to index digi containers
        const uint32_t key = (useFedKey_ || (!legacy_ && mode == sistrip::READOUT_MODE_SCOPE) ||
                              (legacy_ && lmode == sistrip::READOUT_MODE_LEGACY_SCOPE))
                                 ? fed_key
                                 : iconn->detId();

        // Determine APV std::pair number (needed only when using DetId)
        const uint16_t ipair = (useFedKey_ || (!legacy_ && mode == sistrip::READOUT_MODE_SCOPE) ||
                                (legacy_ && lmode == sistrip::READOUT_MODE_LEGACY_SCOPE))
                                   ? 0
                                   : iconn->apvPairNumber();

        const auto& fedChannel = buffer.channel(iconn->fedCh());

#ifdef EDM_ML_DEBUG
        std::stringstream smode;
        if (!legacy_)
          smode << mode;
        else
          smode << lmode;
        LogDebug("SiStripRawToDigi") << "Unpacking FED " << *ifed << " channel " << iconn->fedCh()
                                     << ((!legacy_) ? " " : " legacy ") << "data in mode " << smode.str()
                                     << " for module " << iconn->detId() << " pair " << ipair;
#endif
        if (fedchannelunpacker::isZeroSuppressed(mode, legacy_, lmode)) {
          Registry regItem(key, 0, zs_work_digis_.size(), 0);
          const auto isNonLite = fedchannelunpacker::isNonLiteZS(mode, legacy_, lmode);
          const uint8_t pCode = (isNonLite ? buffer.packetCode(legacy_, iconn->fedCh()) : 0);
          if (isNonLite)
            LogDebug("SiStripRawToDigi") << "Non-lite zero-suppressed mode. Packet code=0x" << std::hex
                                         << uint16_t(pCode) << std::dec;
          const auto st_ch = fedchannelunpacker::unpackZeroSuppressed(
              fedChannel, std::back_inserter(zs_work_digis_), ipair * 256, isNonLite, mode, legacy_, lmode, pCode);
          if (fedchannelunpacker::StatusCode::ZERO_PACKET_CODE == st_ch ||
              fedchannelunpacker::StatusCode::BAD_PACKET_CODE == st_ch) {
            warnings_.add(fmt::format("Invalid packet code {0:#x} for zero-suppressed data", uint16_t(pCode)),
                          fmt::format("FED {0} channel {1}", *ifed, iconn->fedCh()));
          } else if (fedchannelunpacker::StatusCode::SUCCESS != st_ch) {
            warnings_.add("Clusters are not ordered",
                          fmt::format("FED {0} channel {1}: {2}", *ifed, iconn->fedCh(), toString(st_ch)));
            detids.push_back(iconn->detId());  //@@ Possible multiple entries (ok for Giovanni)
            continue;
          }
          if (regItem.index != zs_work_digis_.size()) {
            regItem.length = zs_work_digis_.size() - regItem.index;
            regItem.first = zs_work_digis_[regItem.index].strip();
            zs_work_registry_.push_back(regItem);
          }
          // Common mode values
          if (isNonLite && extractCm_) {
            if ((pCode == PACKET_CODE_ZERO_SUPPRESSED) || (pCode == PACKET_CODE_ZERO_SUPPRESSED10) ||
                (pCode == PACKET_CODE_ZERO_SUPPRESSED8_BOTBOT) || (pCode == PACKET_CODE_ZERO_SUPPRESSED8_TOPBOT)) {
              Registry regItem2(key, 2 * ipair, cm_work_digis_.size(), 2);
              cm_work_digis_.push_back(SiStripRawDigi(fedChannel.cmMedian(0)));
              cm_work_digis_.push_back(SiStripRawDigi(fedChannel.cmMedian(1)));
              cm_work_registry_.push_back(regItem2);
            } else {
              detids.push_back(iconn->detId());  //@@ Possible multiple entries (ok for Giovanni)
              warnings_.add("Problem extracting common modes",
                            fmt::format("FED {0} channel {1}:\n Request for CM median from channel with non-ZS "
                                        "packet code. Packet code is {2}.",
                                        *ifed,
                                        iconn->fedCh(),
                                        pCode));
            }
          }
        } else {
          auto st_ch = fedchannelunpacker::StatusCode::SUCCESS;
          if (fedchannelunpacker::isVirginRaw(mode, legacy_, lmode)) {
            Registry regItem(key, 256 * ipair, virgin_work_digis_.size(), 0);
            LogDebug("SiStripRawToDigi") << "Virgin raw packet code: 0x" << std::hex
                                         << uint16_t(buffer.packetCode(legacy_)) << "  0x"
                                         << uint16_t(fedChannel.packetCode()) << std::dec;
            st_ch = fedchannelunpacker::unpackVirginRaw(
                fedChannel, std::back_inserter(virgin_work_digis_), buffer.packetCode(legacy_));
            if (regItem.index != virgin_work_digis_.size()) {
              regItem.length = virgin_work_digis_.size() - regItem.index;
              virgin_work_registry_.push_back(regItem);
            }
          } else if (fedchannelunpacker::isProcessedRaw(mode, legacy_, lmode)) {
            Registry regItem(key, 256 * ipair, proc_work_digis_.size(), 0);
            st_ch = fedchannelunpacker::unpackProcessedRaw(fedChannel, std::back_inserter(proc_work_digis_));
            if (regItem.index != proc_work_digis_.size()) {
              regItem.length = proc_work_digis_.size() - regItem.index;
              proc_work_registry_.push_back(regItem);
            }
          } else if (fedchannelunpacker::isScopeMode(mode, legacy_, lmode)) {
            Registry regItem(key, 0, scope_work_digis_.size(), 0);
            st_ch = fedchannelunpacker::unpackScope(fedChannel, std::back_inserter(scope_work_digis_));
            if (regItem.index != scope_work_digis_.size()) {
              regItem.length = scope_work_digis_.size() - regItem.index;
              scope_work_registry_.push_back(regItem);
            }
          } else {  // Unknown readout mode! => assume scope mode
            warnings_.add(fmt::format("Unknown FED readout mode ({0})! Assuming SCOPE MODE...", mode));
            Registry regItem(key, 0, scope_work_digis_.size(), 0);
            st_ch = fedchannelunpacker::unpackScope(fedChannel, std::back_inserter(scope_work_digis_));
            if (regItem.index != scope_work_digis_.size()) {
              regItem.length = scope_work_digis_.size() - regItem.index;
              scope_work_registry_.push_back(regItem);
              if (edm::isDebugEnabled()) {
                std::stringstream ss;
                ss << "Extracted " << regItem.length
                   << " SCOPE MODE digis (samples[0] = " << scope_work_digis_[regItem.index] << ") from FED id/ch "
                   << iconn->fedId() << "/" << iconn->fedCh();
                LogTrace("SiStripRawToDigi") << ss.str();
              }
            } else {
              warnings_.add("No SM digis found!");
            }
          }
          if (fedchannelunpacker::StatusCode::SUCCESS != st_ch) {
            warnings_.add(toString(st_ch), fmt::format("FED {0} channel {1}:", *ifed, iconn->fedCh()));
          }
        }
      }  // channel loop
    }    // fed loop

    // bad channels warning
    unsigned int detIdsSize = detids.size();
    if (edm::isDebugEnabled() && detIdsSize) {
      std::ostringstream ss;
      ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
         << " Problems were found in data and " << detIdsSize << " channels could not be unpacked. "
         << "See output of FED Hardware monitoring for more information. ";
      edm::LogWarning(sistrip::mlRawToDigi_) << ss.str();
    }
    if ((errorThreshold_ != 0) && (detIdsSize > errorThreshold_)) {
      edm::LogError("TooManyErrors") << "Total number of errors = " << detIdsSize;
    }

    // update DetSetVectors
    update(scope_mode, virgin_raw, proc_raw, zero_suppr, cm_values);

    // increment event counter
    event_++;

    // no longer first event!
    if (first_) {
      first_ = false;
    }

    // final cleanup, just in case
    cleanupWorkVectors();
  }

  void RawToDigiUnpacker::update(
      RawDigis& scope_mode, RawDigis& virgin_raw, RawDigis& proc_raw, Digis& zero_suppr, RawDigis& common_mode) {
    if (!zs_work_registry_.empty()) {
      std::sort(zs_work_registry_.begin(), zs_work_registry_.end());
      std::vector<edm::DetSet<SiStripDigi> > sorted_and_merged;
      sorted_and_merged.reserve(std::min(zs_work_registry_.size(), size_t(17000)));

      bool errorInData = false;
      std::vector<Registry>::iterator it = zs_work_registry_.begin(), it2 = it + 1, end = zs_work_registry_.end();
      while (it < end) {
        sorted_and_merged.push_back(edm::DetSet<SiStripDigi>(it->detid));
        std::vector<SiStripDigi>& digis = sorted_and_merged.back().data;
        // first count how many digis we have
        size_t len = it->length;
        for (it2 = it + 1; (it2 != end) && (it2->detid == it->detid); ++it2) {
          len += it2->length;
        }
        // reserve memory
        digis.reserve(len);
        // push them in
        for (it2 = it + 0; (it2 != end) && (it2->detid == it->detid); ++it2) {
          digis.insert(digis.end(), &zs_work_digis_[it2->index], &zs_work_digis_[it2->index + it2->length]);
        }
        it = it2;
      }

      // check sorting
      if (!__gnu_cxx::is_sorted(sorted_and_merged.begin(), sorted_and_merged.end())) {
        // this is an error in the code: i DID sort it already!
        throw cms::Exception("Bug Found")
            << "Container must be already sorted!\nat " << __FILE__ << ", line " << __LINE__ << "\n";
      }

      std::vector<edm::DetSet<SiStripDigi> >::iterator iii = sorted_and_merged.begin();
      std::vector<edm::DetSet<SiStripDigi> >::iterator jjj = sorted_and_merged.end();
      for (; iii != jjj; ++iii) {
        if (!__gnu_cxx::is_sorted(iii->begin(), iii->end())) {
          // this might be an error in the data, if the raws from one FED are not sorted
          iii->clear();
          errorInData = true;
        }
      }

      // output error
      if (errorInData)
        edm::LogWarning("CorruptData")
            << "Some modules contained corrupted ZS raw data, and have been skipped in unpacking\n";

      // make output DetSetVector
      edm::DetSetVector<SiStripDigi> zero_suppr_dsv(sorted_and_merged, true);
      zero_suppr.swap(zero_suppr_dsv);
    }

    // Populate final DetSetVector container with VR data
    if (!virgin_work_registry_.empty()) {
      std::sort(virgin_work_registry_.begin(), virgin_work_registry_.end());

      std::vector<edm::DetSet<SiStripRawDigi> > sorted_and_merged;
      sorted_and_merged.reserve(std::min(virgin_work_registry_.size(), size_t(17000)));

      bool errorInData = false;
      std::vector<Registry>::iterator it = virgin_work_registry_.begin(), it2, end = virgin_work_registry_.end();
      while (it < end) {
        sorted_and_merged.push_back(edm::DetSet<SiStripRawDigi>(it->detid));
        std::vector<SiStripRawDigi>& digis = sorted_and_merged.back().data;

        bool isDetOk = true;
        // first count how many digis we have
        int maxFirstStrip = it->first;
        for (it2 = it + 1; (it2 != end) && (it2->detid == it->detid); ++it2) {
          // duplicated APV or data corruption. DO NOT 'break' here!
          if (it2->first <= maxFirstStrip) {
            isDetOk = false;
            continue;
          }
          maxFirstStrip = it2->first;
        }
        if (!isDetOk) {
          errorInData = true;
          it = it2;
          continue;
        }  // skip whole det

        // make room for 256 * (max_apv_pair + 1) Raw Digis
        digis.resize(maxFirstStrip + 256);
        // push them in
        for (it2 = it + 0; (it2 != end) && (it2->detid == it->detid); ++it2) {
          // data corruption. DO NOT 'break' here
          if (it->length != 256) {
            isDetOk = false;
            continue;
          }
          std::copy(&virgin_work_digis_[it2->index], &virgin_work_digis_[it2->index + it2->length], &digis[it2->first]);
        }
        if (!isDetOk) {
          errorInData = true;
          digis.clear();
          it = it2;
          continue;
        }  // skip whole det
        it = it2;
      }

      // output error
      if (errorInData)
        edm::LogWarning("CorruptData")
            << "Some modules contained corrupted virgin raw data, and have been skipped in unpacking\n";

      // check sorting
      if (!__gnu_cxx::is_sorted(sorted_and_merged.begin(), sorted_and_merged.end())) {
        // this is an error in the code: i DID sort it already!
        throw cms::Exception("Bug Found")
            << "Container must be already sorted!\nat " << __FILE__ << ", line " << __LINE__ << "\n";
      }

      // make output DetSetVector
      edm::DetSetVector<SiStripRawDigi> virgin_raw_dsv(sorted_and_merged, true);
      virgin_raw.swap(virgin_raw_dsv);
    }

    // Populate final DetSetVector container with VR data
    if (!proc_work_registry_.empty()) {
      std::sort(proc_work_registry_.begin(), proc_work_registry_.end());

      std::vector<edm::DetSet<SiStripRawDigi> > sorted_and_merged;
      sorted_and_merged.reserve(std::min(proc_work_registry_.size(), size_t(17000)));

      bool errorInData = false;
      std::vector<Registry>::iterator it = proc_work_registry_.begin(), it2, end = proc_work_registry_.end();
      while (it < end) {
        sorted_and_merged.push_back(edm::DetSet<SiStripRawDigi>(it->detid));
        std::vector<SiStripRawDigi>& digis = sorted_and_merged.back().data;

        bool isDetOk = true;
        // first count how many digis we have
        int maxFirstStrip = it->first;
        for (it2 = it + 1; (it2 != end) && (it2->detid == it->detid); ++it2) {
          // duplicated APV or data corruption. DO NOT 'break' here!
          if (it2->first <= maxFirstStrip) {
            isDetOk = false;
            continue;
          }
          maxFirstStrip = it2->first;
        }
        // skip whole det
        if (!isDetOk) {
          errorInData = true;
          it = it2;
          continue;
        }

        // make room for 256 * (max_apv_pair + 1) Raw Digis
        digis.resize(maxFirstStrip + 256);
        // push them in
        for (it2 = it + 0; (it2 != end) && (it2->detid == it->detid); ++it2) {
          // data corruption. DO NOT 'break' here
          if (it->length != 256) {
            isDetOk = false;
            continue;
          }
          std::copy(&proc_work_digis_[it2->index], &proc_work_digis_[it2->index + it2->length], &digis[it2->first]);
        }
        // skip whole det
        if (!isDetOk) {
          errorInData = true;
          digis.clear();
          it = it2;
          continue;
        }
        it = it2;
      }

      // output error
      if (errorInData)
        edm::LogWarning("CorruptData")
            << "Some modules contained corrupted proc raw data, and have been skipped in unpacking\n";

      // check sorting
      if (!__gnu_cxx::is_sorted(sorted_and_merged.begin(), sorted_and_merged.end())) {
        // this is an error in the code: i DID sort it already!
        throw cms::Exception("Bug Found")
            << "Container must be already sorted!\nat " << __FILE__ << ", line " << __LINE__ << "\n";
      }

      // make output DetSetVector
      edm::DetSetVector<SiStripRawDigi> proc_raw_dsv(sorted_and_merged, true);
      proc_raw.swap(proc_raw_dsv);
    }

    // Populate final DetSetVector container with SM data
    if (!scope_work_registry_.empty()) {
      std::sort(scope_work_registry_.begin(), scope_work_registry_.end());

      std::vector<edm::DetSet<SiStripRawDigi> > sorted_and_merged;
      sorted_and_merged.reserve(scope_work_registry_.size());

      bool errorInData = false;
      std::vector<Registry>::iterator it, end;
      for (it = scope_work_registry_.begin(), end = scope_work_registry_.end(); it != end; ++it) {
        sorted_and_merged.push_back(edm::DetSet<SiStripRawDigi>(it->detid));
        std::vector<SiStripRawDigi>& digis = sorted_and_merged.back().data;
        digis.insert(digis.end(), &scope_work_digis_[it->index], &scope_work_digis_[it->index + it->length]);

        if ((it + 1 != end) && (it->detid == (it + 1)->detid)) {
          errorInData = true;
          // let's skip *all* the detsets for that key, as we don't know which is the correct one!
          do {
            ++it;
          } while ((it + 1 != end) && (it->detid == (it + 1)->detid));
        }
      }

      // output error
      if (errorInData)
        edm::LogWarning("CorruptData")
            << "Some fed keys contained corrupted scope mode data, and have been skipped in unpacking\n";

      // check sorting
      if (!__gnu_cxx::is_sorted(sorted_and_merged.begin(), sorted_and_merged.end())) {
        // this is an error in the code: i DID sort it already!
        throw cms::Exception("Bug Found")
            << "Container must be already sorted!\nat " << __FILE__ << ", line " << __LINE__ << "\n";
      }

      // make output DetSetVector
      edm::DetSetVector<SiStripRawDigi> scope_mode_dsv(sorted_and_merged, true);
      scope_mode.swap(scope_mode_dsv);
    }

    // Populate DetSetVector with Common Mode values
    if (extractCm_) {
      // Populate final DetSetVector container with VR data
      if (!cm_work_registry_.empty()) {
        std::sort(cm_work_registry_.begin(), cm_work_registry_.end());

        std::vector<edm::DetSet<SiStripRawDigi> > sorted_and_merged;
        sorted_and_merged.reserve(std::min(cm_work_registry_.size(), size_t(17000)));

        bool errorInData = false;
        std::vector<Registry>::iterator it = cm_work_registry_.begin(), it2, end = cm_work_registry_.end();
        while (it < end) {
          sorted_and_merged.push_back(edm::DetSet<SiStripRawDigi>(it->detid));
          std::vector<SiStripRawDigi>& digis = sorted_and_merged.back().data;

          bool isDetOk = true;
          // first count how many digis we have
          int maxFirstStrip = it->first;
          for (it2 = it + 1; (it2 != end) && (it2->detid == it->detid); ++it2) {
            // duplicated APV or data corruption. DO NOT 'break' here!
            if (it2->first <= maxFirstStrip) {
              isDetOk = false;
              continue;
            }
            maxFirstStrip = it2->first;
          }
          if (!isDetOk) {
            errorInData = true;
            it = it2;
            continue;
          }  // skip whole det

          // make room for 2 * (max_apv_pair + 1) Common mode values
          digis.resize(maxFirstStrip + 2);
          // push them in
          for (it2 = it + 0; (it2 != end) && (it2->detid == it->detid); ++it2) {
            // data corruption. DO NOT 'break' here
            if (it->length != 2) {
              isDetOk = false;
              continue;
            }
            std::copy(&cm_work_digis_[it2->index], &cm_work_digis_[it2->index + it2->length], &digis[it2->first]);
          }
          if (!isDetOk) {
            errorInData = true;
            digis.clear();
            it = it2;
            continue;
          }  // skip whole det
          it = it2;
        }

        // output error
        if (errorInData)
          edm::LogWarning("CorruptData")
              << "Some modules contained corrupted common mode data, and have been skipped in unpacking\n";

        // check sorting
        if (!__gnu_cxx::is_sorted(sorted_and_merged.begin(), sorted_and_merged.end())) {
          // this is an error in the code: i DID sort it already!
          throw cms::Exception("Bug Found")
              << "Container must be already sorted!\nat " << __FILE__ << ", line " << __LINE__ << "\n";
        }

        // make output DetSetVector
        edm::DetSetVector<SiStripRawDigi> common_mode_dsv(sorted_and_merged, true);
        common_mode.swap(common_mode_dsv);
      }
    }
  }

  void RawToDigiUnpacker::cleanupWorkVectors() {
    // Clear working areas and registries

    localRA.update(zs_work_digis_.size());
    zs_work_registry_.clear();
    zs_work_digis_.clear();
    zs_work_digis_.shrink_to_fit();
    assert(zs_work_digis_.capacity() == 0);
    virgin_work_registry_.clear();
    virgin_work_digis_.clear();
    proc_work_registry_.clear();
    proc_work_digis_.clear();
    scope_work_registry_.clear();
    scope_work_digis_.clear();
    cm_work_registry_.clear();
    cm_work_digis_.clear();
  }

  void RawToDigiUnpacker::triggerFed(const FEDRawDataCollection& buffers,
                                     SiStripEventSummary& summary,
                                     const uint32_t& event) {
    // Pointer to data (recast as 32-bit words) and number of 32-bit words
    const uint32_t* data_u32 = nullptr;
    uint32_t size_u32 = 0;

    // Search mode
    if (triggerFedId_ < 0) {
      uint16_t ifed = 0;
      while (triggerFedId_ < 0 && ifed < 1 + FEDNumbering::lastFEDId()) {
        const FEDRawData& trigger_fed = buffers.FEDData(ifed);
        if (trigger_fed.data() && trigger_fed.size()) {
          const uint8_t* temp = trigger_fed.data();
          data_u32 = reinterpret_cast<const uint32_t*>(temp) + FEDHeader::length / sizeof(uint32_t) + 1;
          size_u32 = trigger_fed.size() / sizeof(uint32_t) - FEDHeader::length / sizeof(uint32_t) - 1;
          const FEDTrailer fedTrailer(temp + trigger_fed.size() - FEDTrailer::length);
          if (fedTrailer.conscheck() == 0xDEADFACE) {
            triggerFedId_ = ifed;
            if (edm::isDebugEnabled()) {
              std::stringstream ss;
              ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
                 << " Search mode for 'trigger FED' activated!"
                 << " Found 'trigger FED' info with id " << triggerFedId_;
              LogTrace("SiStripRawToDigi") << ss.str();
            }
          }
        }
        ifed++;
      }
      if (triggerFedId_ < 0) {
        triggerFedId_ = 0;
        if (edm::isDebugEnabled()) {
          std::stringstream ss;
          ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
             << " Search mode for 'trigger FED' activated!"
             << " 'Trigger FED' info not found!";
          edm::LogWarning(sistrip::mlRawToDigi_) << ss.str();
        }
      }
    }

    // "Trigger FED" id given in .cfg file
    else if (triggerFedId_ > 0) {
      const FEDRawData& trigger_fed = buffers.FEDData(triggerFedId_);
      if (trigger_fed.data() && trigger_fed.size()) {
        const uint8_t* temp = trigger_fed.data();
        data_u32 = reinterpret_cast<const uint32_t*>(temp) + FEDHeader::length / sizeof(uint32_t) + 1;
        size_u32 = trigger_fed.size() / sizeof(uint32_t) - FEDHeader::length / sizeof(uint32_t) - 1;
        const FEDTrailer fedTrailer(temp + trigger_fed.size() - FEDTrailer::length);
        if (fedTrailer.conscheck() != 0xDEADFACE) {
          if (edm::isDebugEnabled()) {
            edm::LogWarning(sistrip::mlRawToDigi_) << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
                                                   << " Unexpected stamp found in DAQ trailer (ie, not 0xDEADFACE)!"
                                                   << " Buffer appears not to contain 'trigger FED' data!";
          }
          triggerFedId_ = 0;
        }
      }

    } else {
      triggerFedId_ = 0;
      data_u32 = nullptr;
      size_u32 = 0;
    }

    // Populate summary object with commissioning information
    if (triggerFedId_ > 0) {
      // Some checks
      if (!data_u32) {
        if (edm::isDebugEnabled()) {
          std::stringstream ss;
          ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
             << " NULL pointer to 'trigger FED' data";
          edm::LogWarning(sistrip::mlRawToDigi_) << ss.str();
        }
        return;
      }
      if (size_u32 < sizeof(TFHeaderDescription) / sizeof(uint32_t)) {
        if (edm::isDebugEnabled()) {
          std::stringstream ss;
          ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
             << " Unexpected 'Trigger FED' data size [32-bit words]: " << size_u32;
          edm::LogWarning(sistrip::mlRawToDigi_) << ss.str();
        }
        return;
      }

      // Write event-specific data to event
      const TFHeaderDescription* header = (const TFHeaderDescription*)data_u32;
      summary.event(static_cast<uint32_t>(header->getFedEventNumber()));
      summary.bx(static_cast<uint32_t>(header->getBunchCrossing()));

      // Write commissioning information to event
      uint32_t hsize = sizeof(TFHeaderDescription) / sizeof(uint32_t);
      const uint32_t* head = &data_u32[hsize];
      summary.commissioningInfo(head, event);
      summary.triggerFed(triggerFedId_);
    }

    // Some debug
    if (summary.isSet() && once_) {
      if (edm::isDebugEnabled()) {
        std::stringstream ss;
        ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
           << " EventSummary built from \"trigger FED\":" << std::endl
           << summary;
        LogTrace("SiStripRawToDigi") << ss.str();
      }
      once_ = false;
    }
  }

  void RawToDigiUnpacker::locateStartOfFedBuffer(const uint16_t& fed_id, const FEDRawData& input, FEDRawData& output) {
    // Check size of input buffer
    if (input.size() < 24) {
      output.resize(input.size());  // Return UNadjusted buffer start position and size
      memcpy(output.data(), input.data(), input.size());
      if (edm::isDebugEnabled()) {
        std::stringstream ss;
        ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "] "
           << "Input FEDRawData with FED id " << fed_id << " has size " << input.size();
        edm::LogWarning(sistrip::mlRawToDigi_) << ss.str();
      }
      return;
    }

    // Iterator through buffer to find DAQ header
    bool found = false;
    uint16_t ichar = 0;
    while (ichar < input.size() - 16 && !found) {
      uint16_t offset =
          headerBytes_ < 0 ? ichar : headerBytes_;  // Negative value means use "search mode" to find DAQ header
      const uint32_t* input_u32 = reinterpret_cast<const uint32_t*>(input.data() + offset);
      const uint32_t* fed_trailer = reinterpret_cast<const uint32_t*>(input.data() + input.size() - 8);

      // see info on FED 32-bit swapping at end-of-file

      bool old_vme_header = (input_u32[0] & 0xF0000000) == 0x50000000 && (fed_trailer[0] & 0xF0000000) == 0xA0000000 &&
                            ((fed_trailer[0] & 0x00FFFFFF) * 0x8) == (input.size() - offset);

      bool old_slink_header = (input_u32[1] & 0xF0000000) == 0x50000000 &&
                              (fed_trailer[1] & 0xF0000000) == 0xA0000000 &&
                              ((fed_trailer[1] & 0x00FFFFFF) * 0x8) == (input.size() - offset);

      bool old_slink_payload = (input_u32[3] & 0xFF000000) == 0xED000000;

      bool new_buffer_format = (input_u32[2] & 0xFF000000) == 0xC5000000;

      if (old_vme_header) {
        // Found DAQ header at byte position 'offset'
        found = true;
        output.resize(input.size() - offset);
        memcpy(output.data(),           // target
               input.data() + offset,   // source
               input.size() - offset);  // nbytes
        if (headerBytes_ < 0) {
          if (edm::isDebugEnabled()) {
            std::stringstream ss;
            ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
               << " Buffer for FED id " << fed_id << " has been found at byte position " << offset << " with a size of "
               << input.size() - offset << " bytes."
               << " Adjust the configurable 'AppendedBytes' to " << offset;
            LogTrace("SiStripRawToDigi") << ss.str();
          }
        }

      } else if (old_slink_header) {
        if (old_slink_payload) {
          // Found DAQ header (with MSB and LSB 32-bit words swapped) at byte position 'offset'
          found = true;
          output.resize(input.size() - offset);
          uint32_t* output_u32 = reinterpret_cast<uint32_t*>(output.data());
          uint16_t iter = offset;
          while (iter < output.size() / sizeof(uint32_t)) {
            output_u32[iter] = input_u32[iter + 1];
            output_u32[iter + 1] = input_u32[iter];
            iter += 2;
          }
          if (headerBytes_ < 0) {
            if (edm::isDebugEnabled()) {
              std::stringstream ss;
              ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
                 << " Buffer (with MSB and LSB 32-bit words swapped) for FED id " << fed_id
                 << " has been found at byte position " << offset << " with a size of " << output.size() << " bytes."
                 << " Adjust the configurable 'AppendedBytes' to " << offset;
              LogTrace("SiStripRawToDigi") << ss.str();
            }
          }

        } else if (new_buffer_format) {
          // Found DAQ header at byte position 'offset'
          found = true;
          output.resize(input.size() - offset);
          memcpy(output.data(),           // target
                 input.data() + offset,   // source
                 input.size() - offset);  // nbytes
          if (headerBytes_ < 0) {
            if (edm::isDebugEnabled()) {
              std::stringstream ss;
              ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
                 << " Buffer for FED id " << fed_id << " has been found at byte position " << offset
                 << " with a size of " << input.size() - offset << " bytes."
                 << " Adjust the configurable 'AppendedBytes' to " << offset;
              LogTrace("SiStripRawToDigi") << ss.str();
            }
          }

        } else {
          headerBytes_ < 0 ? found = false : found = true;
        }
      } else {
        headerBytes_ < 0 ? found = false : found = true;
      }
      ichar++;
    }

    // Check size of output buffer
    if (output.size() == 0) {
      // Did not find DAQ header after search => return buffer with null size
      output.resize(0);                        //@@ NULL SIZE
      memcpy(output.data(), input.data(), 0);  //@@ NULL SIZE
      if (edm::isDebugEnabled()) {
        std::stringstream ss;
        if (headerBytes_ < 0) {
          ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
             << " DAQ header not found within buffer for FED id: " << fed_id;
        } else {
          const uint32_t* input_u32 = reinterpret_cast<const uint32_t*>(input.data());
          ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
             << " DAQ header not found at expected location for FED id: " << fed_id << std::endl
             << " First 64-bit word of buffer is 0x" << std::hex << std::setfill('0') << std::setw(8) << input_u32[0]
             << std::setfill('0') << std::setw(8) << input_u32[1] << std::dec << std::endl
             << " Adjust 'AppendedBytes' configurable to '-1' to activate 'search mode'";
        }
        edm::LogWarning(sistrip::mlRawToDigi_) << ss.str();
      }

    } else if (output.size() < 24) {  // Found DAQ header after search, but too few words

      if (edm::isDebugEnabled()) {
        std::stringstream ss;
        ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
           << " Unexpected buffer size! FEDRawData with FED id " << fed_id << " has size " << output.size();
        edm::LogWarning(sistrip::mlRawToDigi_) << ss.str();
      }
    }
  }

  void RawToDigiUnpacker::updateEventSummary(const sistrip::FEDBuffer& fed, SiStripEventSummary& summary) {
    summary.event(fed.daqHeader().l1ID());
    summary.bx(fed.daqHeader().bxID());

    // Retrieve contents of DAQ registers

    sistrip::FEDDAQEventType readout_mode = fed.daqEventType();
    uint32_t daq1 = sistrip::invalid32_;
    uint32_t daq2 = sistrip::invalid32_;

    if (fed.headerType() == sistrip::HEADER_TYPE_FULL_DEBUG) {
      const sistrip::FEDFullDebugHeader* header = nullptr;
      header = dynamic_cast<const sistrip::FEDFullDebugHeader*>(fed.feHeader());
      daq1 = static_cast<uint32_t>(header->daqRegister());
      daq2 = static_cast<uint32_t>(header->daqRegister2());
    }

    // If FED DAQ registers contain info, update (and possibly overwrite) EventSummary
    if (daq1 != 0 && daq1 != sistrip::invalid32_) {
      summary.triggerFed(triggerFedId_);
      summary.fedReadoutMode(readout_mode);
      summary.commissioningInfo(daq1, daq2);

      if (summary.isSet() && once_) {
        if (edm::isDebugEnabled()) {
          std::stringstream ss;
          ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
             << " EventSummary built from FED DAQ registers:" << std::endl
             << summary;
          LogTrace("SiStripRawToDigi") << ss.str();
        }
        once_ = false;
      }
    }
  }

  void RawToDigiUnpacker::dumpRawData(uint16_t fed_id, const FEDRawData& buffer, std::stringstream& ss) {
    ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
       << " Dump of buffer for FED id " << fed_id << std::endl
       << " Buffer contains " << buffer.size() << " bytes (NB: payload is byte-swapped)" << std::endl;

    if (false) {
      const uint32_t* buffer_u32 = reinterpret_cast<const uint32_t*>(buffer.data());
      unsigned int empty = 0;

      ss << "Byte->   4 5 6 7 0 1 2 3\n";
      for (uint32_t i = 0; i < buffer.size() / 8; i++) {
        unsigned int temp0 = buffer_u32[i * 2] & sistrip::invalid32_;
        unsigned int temp1 = buffer_u32[i * 2 + 1] & sistrip::invalid32_;
        if (!temp0 && !temp1) {
          empty++;
        } else {
          if (empty) {
            ss << "        [ empty  words ]" << std::endl;
            empty = 0;
          }
          ss << std::dec << std::setfill(' ') << std::setw(6) << i * 8 << ": " << std::hex << std::setfill('0')
             << std::setw(8) << temp0 << std::setfill('0') << std::setw(8) << temp1 << std::dec << std::endl;
        }
      }

    } else {
      ss << "  Byte |  <---- Byte order ----<  | Byte" << std::endl;
      ss << "  cntr |  7  6  5  4  3  2  1  0  | cntr" << std::endl;
      for (uint32_t i = 0; i < buffer.size() / 8; i++) {
        //if ( i>=20 && ((i+4)<(buffer.size()/8)) ) { continue; }
        uint16_t tmp0 = buffer.data()[i * 8 + 0] & 0xFF;
        uint16_t tmp1 = buffer.data()[i * 8 + 1] & 0xFF;
        uint16_t tmp2 = buffer.data()[i * 8 + 2] & 0xFF;
        uint16_t tmp3 = buffer.data()[i * 8 + 3] & 0xFF;
        uint16_t tmp4 = buffer.data()[i * 8 + 4] & 0xFF;
        uint16_t tmp5 = buffer.data()[i * 8 + 5] & 0xFF;
        uint16_t tmp6 = buffer.data()[i * 8 + 6] & 0xFF;
        uint16_t tmp7 = buffer.data()[i * 8 + 7] & 0xFF;
        //  if ( !tmp0 && !tmp1 && !tmp2 && !tmp3 &&
        //       !tmp4 && !tmp5 && !tmp6 && !tmp7 ) { empty++; }
        //  else {
        //    if ( empty ) {
        //      ss << "         [.."
        //         << std::dec << std::setfill('.') << std::setw(4) << empty
        //         << " null words....]" << std::endl;
        //      empty = 0;
        //    }
        ss << std::dec << std::setfill(' ') << std::setw(6) << i * 8 + 7 << " : " << std::hex << std::setfill('0')
           << std::setw(2) << tmp7 << " " << std::setfill('0') << std::setw(2) << tmp6 << " " << std::setfill('0')
           << std::setw(2) << tmp5 << " " << std::setfill('0') << std::setw(2) << tmp4 << " " << std::setfill('0')
           << std::setw(2) << tmp3 << " " << std::setfill('0') << std::setw(2) << tmp2 << " " << std::setfill('0')
           << std::setw(2) << tmp1 << " " << std::setfill('0') << std::setw(2) << tmp0 << std::dec << " :"
           << std::setfill(' ') << std::setw(6) << i * 8 << std::endl;
        //  }
      }
    }
    ss << "[sistrip::RawToDigiUnpacker::" << __func__ << "]"
       << " End of FED buffer";
  }
}  // namespace sistrip

/*
  
Some info on FED buffer 32-bit word swapping. 

Table below indicates if data are swapped relative to the "old"
VME format (as originally expected by the Fed9UEvent class).

-------------------------------------------
| SWAPPED?    |         DATA FORMAT       |
| (wrt "OLD") | OLD (0xED)  | NEW (0xC5)  |
|             | VME | SLINK | VME | SLINK |
-------------------------------------------
| DAQ HEADER  |  N  |   Y   |  Y  |   Y   |
| TRK HEADER  |  N  |   Y   |  N  |   N   |
| PAYLOAD     |  N  |   Y   |  N  |   N   |
| DAQ TRAILER |  N  |   Y   |  Y  |   Y   |
-------------------------------------------

So, in code, we check in code order of bytes in DAQ header/trailer only:
-> if "old_vme_header",           then old format read out via vme, so do nothing.
-> else if "old_slink_header",    then data may be wrapped, so check additionally the TRK header:
---> if "old_slink_payload",       then old format read out via slink, so swap all data;
---> else if "new_buffer_format",  then new format, handled internally by Fed9UEvent, so do nothing.

Pattern matching to find DAQ and tracker headers, and DAQ trailer:
DAQ header,  4 bits, in field  |BOE_1|      with value 0x5
DAQ trailer, 4 bits, in field  |EOE_1|      with value 0xA
TRK header,  8 bits, in field  |Hdr format| with value 0xED or 0xC5

-------------------------------------------------------------------------------------------
| SWAPPED?    |                                 DATA FORMAT                               |
| (wrt "OLD") |               OLD (0xED)            |               NEW (0xC5)            |
|             |       VME        |      SLINK       |       VME        |      SLINK       |
-------------------------------------------------------------------------------------------
| DAQ HEADER  | ........5....... | 5............... | 5............... | 5............... |
| TRK HEADER  | ........ED...... | ED.............. | ........C5...... | ........C5...... |
| PAYLOAD     | ..........EA.... | ..EA............ | ..EA............ | ............EA.. | 
| DAQ TRAILER | ........A....... | A............... | A............... | A............... |
-------------------------------------------------------------------------------------------

*/