diff --git a/DataFormats/Detectors/CMakeLists.txt b/DataFormats/Detectors/CMakeLists.txt
index 18b0ed448459c..a4ad99788afb7 100644
--- a/DataFormats/Detectors/CMakeLists.txt
+++ b/DataFormats/Detectors/CMakeLists.txt
@@ -21,7 +21,7 @@ add_subdirectory(ZDC)
 add_subdirectory(TRD)
 add_subdirectory(PHOS)
 add_subdirectory(CPV)
-
+add_subdirectory(CTP)
 if(ENABLE_UPGRADES)
   add_subdirectory(Upgrades)
 else()
diff --git a/DataFormats/Detectors/CTP/CMakeLists.txt b/DataFormats/Detectors/CTP/CMakeLists.txt
new file mode 100644
index 0000000000000..5fb16dad4f15f
--- /dev/null
+++ b/DataFormats/Detectors/CTP/CMakeLists.txt
@@ -0,0 +1,19 @@
+# Copyright CERN and copyright holders of ALICE O2. This software is distributed
+# under the terms of the GNU General Public License v3 (GPL Version 3), copied
+# verbatim in the file "COPYING".
+#
+# See http://alice-o2.web.cern.ch/license for full licensing information.
+#
+# In applying this license CERN does not waive the privileges and immunities
+# granted to it by virtue of its status as an Intergovernmental Organization or
+# submit itself to any jurisdiction.
+
+o2_add_library(DataFormatsCTP
+  SOURCES src/Digits.cxx
+  PUBLIC_LINK_LIBRARIES O2::CommonDataFormat
+                        O2::Headers
+                        O2::SimulationDataFormat
+                        O2::DataFormatsFT0)
+o2_target_root_dictionary(DataFormatsCTP
+                          HEADERS include/DataFormatsCTP/Digits.h)
+
diff --git a/DataFormats/Detectors/CTP/include/DataFormatsCTP/Digits.h b/DataFormats/Detectors/CTP/include/DataFormatsCTP/Digits.h
new file mode 100644
index 0000000000000..1c2de16b31b92
--- /dev/null
+++ b/DataFormats/Detectors/CTP/include/DataFormatsCTP/Digits.h
@@ -0,0 +1,52 @@
+// Copyright CERN and copyright holders of ALICE O2. This software is
+// distributed under the terms of the GNU General Public License v3 (GPL
+// Version 3), copied verbatim in the file "COPYING".
+//
+// See http://alice-o2.web.cern.ch/license for full licensing information.
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#ifndef _CTP_DIGITS_H_
+#define _CTP_DIGITS_H_
+#include "DetectorsCommonDataFormats/DetID.h"
+#include "CommonDataFormat/InteractionRecord.h"
+#include "DataFormatsFT0/Digit.h"
+#include <bitset>
+#include <iosfwd>
+
+namespace o2
+{
+namespace ctp
+{
+static constexpr uint32_t CTP_NINPUTS = 46;
+static constexpr uint32_t CTP_NCLASSES = 64;
+static constexpr uint32_t CTP_MAXL0PERDET = 5;
+// Positions of CTP Detector inputs in CTPInputMask
+static constexpr std::pair<uint32_t, std::bitset<CTP_MAXL0PERDET>> CTP_INPUTMASK_FV0(0, 0x1f);
+static constexpr std::pair<uint32_t, std::bitset<CTP_MAXL0PERDET>> CTP_INPUTMASK_FT0(5, 0x1f);
+struct CTPDigit {
+  o2::InteractionRecord mIntRecord;
+  std::bitset<CTP_NINPUTS> mCTPInputMask;
+  std::bitset<CTP_NCLASSES> mCTPClassMask;
+  CTPDigit() = default;
+  void printStream(std::ostream& stream) const;
+  ClassDefNV(CTPDigit, 1);
+};
+struct CTPInputDigit {
+  o2::InteractionRecord mIntRecord;
+  std::bitset<CTP_MAXL0PERDET> mInputsMask;
+  std::int32_t mDetector;
+  CTPInputDigit() = default;
+  CTPInputDigit(o2::InteractionRecord IntRecord, std::bitset<CTP_MAXL0PERDET> InputsMask, uint32_t DetID)
+  {
+    mIntRecord = IntRecord;
+    mInputsMask = InputsMask;
+    mDetector = DetID;
+  }
+  ClassDefNV(CTPInputDigit, 1)
+};
+} // namespace ctp
+} // namespace o2
+#endif //_CTP_DIGITS_H
diff --git a/DataFormats/Detectors/CTP/src/DataFormatsCTPLinkDef.h b/DataFormats/Detectors/CTP/src/DataFormatsCTPLinkDef.h
new file mode 100644
index 0000000000000..c155641020168
--- /dev/null
+++ b/DataFormats/Detectors/CTP/src/DataFormatsCTPLinkDef.h
@@ -0,0 +1,20 @@
+// Copyright CERN and copyright holders of ALICE O2. This software is
+// distributed under the terms of the GNU General Public License v3 (GPL
+// Version 3), copied verbatim in the file "COPYING".
+//
+// See http://alice-o2.web.cern.ch/license for full licensing information.
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#ifdef __CLING__
+
+#pragma link off all globals;
+#pragma link off all classes;
+#pragma link off all functions;
+#pragma link C++ class o2::ctp::CTPDigit + ;
+#pragma link C++ class vector < o2::ctp::CTPDigit> + ;
+#pragma link C++ class o2::ctp::CTPInputDigit + ;
+#pragma link C++ class vector < o2::ctp::CTPInputDigit> + ;
+#endif
diff --git a/DataFormats/Detectors/CTP/src/Digits.cxx b/DataFormats/Detectors/CTP/src/Digits.cxx
new file mode 100644
index 0000000000000..7b02a59f6312c
--- /dev/null
+++ b/DataFormats/Detectors/CTP/src/Digits.cxx
@@ -0,0 +1,20 @@
+// Copyright CERN and copyright holders of ALICE O2. This software is
+// distributed under the terms of the GNU General Public License v3 (GPL
+// Version 3), copied verbatim in the file "COPYING".
+//
+// See http://alice-o2.web.cern.ch/license for full licensing information.
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#include "DataFormatsCTP/Digits.h"
+#include <iostream>
+
+using namespace o2::ctp;
+
+void CTPDigit::printStream(std::ostream& stream) const
+{
+  stream << "CTP Digit:  BC " << mIntRecord.bc << " orbit " << mIntRecord.orbit << std::endl;
+  stream << "Input Mask: " << mCTPInputMask << " Class Mask:  " << mCTPClassMask << std::endl;
+}
\ No newline at end of file
diff --git a/DataFormats/Detectors/Common/include/DetectorsCommonDataFormats/DetID.h b/DataFormats/Detectors/Common/include/DetectorsCommonDataFormats/DetID.h
index 5db215c4457b7..d0152ee515eb8 100644
--- a/DataFormats/Detectors/Common/include/DetectorsCommonDataFormats/DetID.h
+++ b/DataFormats/Detectors/Common/include/DetectorsCommonDataFormats/DetID.h
@@ -68,13 +68,14 @@ class DetID
   static constexpr ID FV0 = 13;
   static constexpr ID FDD = 14;
   static constexpr ID ACO = 15;
+  static constexpr ID CTP = 16;
 #ifdef ENABLE_UPGRADES
-  static constexpr ID IT3 = 16;
-  static constexpr ID TRK = 17;
-  static constexpr ID FT3 = 18;
+  static constexpr ID IT3 = 17;
+  static constexpr ID TRK = 18;
+  static constexpr ID FT3 = 19;
   static constexpr ID Last = FT3;
 #else
-  static constexpr ID Last = ACO; ///< if extra detectors added, update this !!!
+  static constexpr ID Last = CTP; ///< if extra detectors added, update this !!!
 #endif
   static constexpr ID First = ITS;
 
@@ -135,9 +136,9 @@ class DetID
 
   static constexpr const char* sDetNames[nDetectors + 1] = ///< defined detector names
 #ifdef ENABLE_UPGRADES
-    {"ITS", "TPC", "TRD", "TOF", "PHS", "CPV", "EMC", "HMP", "MFT", "MCH", "MID", "ZDC", "FT0", "FV0", "FDD", "ACO", "IT3", "TRK", "FT3", nullptr};
+    {"ITS", "TPC", "TRD", "TOF", "PHS", "CPV", "EMC", "HMP", "MFT", "MCH", "MID", "ZDC", "FT0", "FV0", "FDD", "ACO", "CTP", "IT3", "TRK", "FT3", nullptr};
 #else
-    {"ITS", "TPC", "TRD", "TOF", "PHS", "CPV", "EMC", "HMP", "MFT", "MCH", "MID", "ZDC", "FT0", "FV0", "FDD", "ACO", nullptr};
+    {"ITS", "TPC", "TRD", "TOF", "PHS", "CPV", "EMC", "HMP", "MFT", "MCH", "MID", "ZDC", "FT0", "FV0", "FDD", "ACO", "CTP", nullptr};
 #endif
   // detector names, will be defined in DataSources
   static constexpr std::array<mask_t, nDetectors> sMasks = ///< detectot masks
@@ -155,7 +156,8 @@ class DetID
     sOrigins = ///< detector data origins
     {o2h::gDataOriginITS, o2h::gDataOriginTPC, o2h::gDataOriginTRD, o2h::gDataOriginTOF, o2h::gDataOriginPHS,
      o2h::gDataOriginCPV, o2h::gDataOriginEMC, o2h::gDataOriginHMP, o2h::gDataOriginMFT, o2h::gDataOriginMCH,
-     o2h::gDataOriginMID, o2h::gDataOriginZDC, o2h::gDataOriginFT0, o2h::gDataOriginFV0, o2h::gDataOriginFDD, o2h::gDataOriginACO
+     o2h::gDataOriginMID, o2h::gDataOriginZDC, o2h::gDataOriginFT0, o2h::gDataOriginFV0, o2h::gDataOriginFDD,
+     o2h::gDataOriginACO, o2h::gDataOriginCTP
 #ifdef ENABLE_UPGRADES
      ,
      o2h::gDataOriginIT3, o2h::gDataOriginTRK, o2h::gDataOriginFT3
diff --git a/Detectors/CMakeLists.txt b/Detectors/CMakeLists.txt
index 1a5c7813cec03..41a3e8a0da254 100644
--- a/Detectors/CMakeLists.txt
+++ b/Detectors/CMakeLists.txt
@@ -14,6 +14,7 @@ add_subdirectory(CTF)
 
 add_subdirectory(Passive) # must be first as some detector's macros use it
 
+add_subdirectory(CTP)
 add_subdirectory(PHOS)
 add_subdirectory(CPV)
 add_subdirectory(EMCAL)
diff --git a/Detectors/CTP/CMakeLists.txt b/Detectors/CTP/CMakeLists.txt
new file mode 100644
index 0000000000000..2f0c018d5ebbc
--- /dev/null
+++ b/Detectors/CTP/CMakeLists.txt
@@ -0,0 +1,12 @@
+# Copyright CERN and copyright holders of ALICE O2. This software is distributed
+# under the terms of the GNU General Public License v3 (GPL Version 3), copied
+# verbatim in the file "COPYING".
+#
+# See http://alice-o2.web.cern.ch/license for full licensing information.
+#
+# In applying this license CERN does not waive the privileges and immunities
+# granted to it by virtue of its status as an Intergovernmental Organization or
+# submit itself to any jurisdiction.
+
+add_subdirectory(simulation)
+add_subdirectory(workflow)
diff --git a/Detectors/CTP/simulation/CMakeLists.txt b/Detectors/CTP/simulation/CMakeLists.txt
new file mode 100644
index 0000000000000..f54e0ff4d0814
--- /dev/null
+++ b/Detectors/CTP/simulation/CMakeLists.txt
@@ -0,0 +1,17 @@
+# Copyright CERN and copyright holders of ALICE O2. This software is distributed
+# under the terms of the GNU General Public License v3 (GPL Version 3), copied
+# verbatim in the file "COPYING".
+#
+# See http://alice-o2.web.cern.ch/license for full licensing information.
+#
+# In applying this license CERN does not waive the privileges and immunities
+# granted to it by virtue of its status as an Intergovernmental Organization or
+# submit itself to any jurisdiction.
+
+o2_add_library(CTPSimulation
+  SOURCES src/Digitizer.cxx
+  PUBLIC_LINK_LIBRARIES O2::SimulationDataFormat O2::Framework
+  O2::DataFormatsCTP
+  O2::Headers)
+o2_target_root_dictionary(CTPSimulation HEADERS
+  include/CTPSimulation/Digitizer.h)
\ No newline at end of file
diff --git a/Detectors/CTP/simulation/include/CTPSimulation/Digitizer.h b/Detectors/CTP/simulation/include/CTPSimulation/Digitizer.h
new file mode 100644
index 0000000000000..6bcfb29467da1
--- /dev/null
+++ b/Detectors/CTP/simulation/include/CTPSimulation/Digitizer.h
@@ -0,0 +1,36 @@
+// Copyright CERN and copyright holders of ALICE O2. This software is
+// distributed under the terms of the GNU General Public License v3 (GPL
+// Version 3), copied verbatim in the file "COPYING".
+//
+// See http://alice-o2.web.cern.ch/license for full licensing information.
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+#ifndef ALICEO2_CTP_DIGITIZER_H
+#define ALICEO2_CTP_DIGITIZER_H
+
+#include "CommonDataFormat/InteractionRecord.h"
+#include "DataFormatsCTP/Digits.h"
+
+#include <gsl/span>
+
+namespace o2
+{
+namespace ctp
+{
+class Digitizer
+{
+ public:
+  Digitizer() = default;
+  ~Digitizer() = default;
+  std::vector<CTPDigit> process(const gsl::span<o2::ctp::CTPInputDigit> digits);
+  void calculateClassMask(std::vector<const CTPInputDigit*> inputs, std::bitset<CTP_NCLASSES>& classmask);
+  void init();
+
+ private:
+  ClassDefNV(Digitizer, 1);
+};
+} // namespace ctp
+} // namespace o2
+#endif //ALICEO2_CTP_DIGITIZER_H
diff --git a/Detectors/CTP/simulation/src/CTPSimulationLinkDef.h b/Detectors/CTP/simulation/src/CTPSimulationLinkDef.h
new file mode 100644
index 0000000000000..af1e5c8043e99
--- /dev/null
+++ b/Detectors/CTP/simulation/src/CTPSimulationLinkDef.h
@@ -0,0 +1,17 @@
+// Copyright CERN and copyright holders of ALICE O2. This software is
+// distributed under the terms of the GNU General Public License v3 (GPL
+// Version 3), copied verbatim in the file "COPYING".
+//
+// See http://alice-o2.web.cern.ch/license for full licensing information.
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+#ifdef __CLING__
+
+#pragma link off all globals;
+#pragma link off all classes;
+#pragma link off all functions;
+
+#pragma link C++ class o2::ctp::Digitizer + ;
+#endif
\ No newline at end of file
diff --git a/Detectors/CTP/simulation/src/Digitizer.cxx b/Detectors/CTP/simulation/src/Digitizer.cxx
new file mode 100644
index 0000000000000..dceb22d2efb4d
--- /dev/null
+++ b/Detectors/CTP/simulation/src/Digitizer.cxx
@@ -0,0 +1,76 @@
+// Copyright CERN and copyright holders of ALICE O2. This software is
+// distributed under the terms of the GNU General Public License v3 (GPL
+// Version 3), copied verbatim in the file "COPYING".
+//
+// See http://alice-o2.web.cern.ch/license for full licensing information.
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#include "CTPSimulation/Digitizer.h"
+#include "TRandom.h"
+#include <cassert>
+#include "FairLogger.h"
+#include <bitset>
+
+using namespace o2::ctp;
+
+ClassImp(Digitizer);
+
+std::vector<CTPDigit> Digitizer::process(const gsl::span<o2::ctp::CTPInputDigit> digits)
+{
+  std::map<o2::InteractionRecord, std::vector<const CTPInputDigit*>> prerawdata;
+  for (auto const& inp : digits) {
+    auto res = prerawdata.find(inp.mIntRecord);
+    if (res == prerawdata.end()) {
+      std::vector<const CTPInputDigit*> inputs;
+      inputs.push_back(&inp);
+      prerawdata[inp.mIntRecord] = inputs;
+    } else {
+      res->second.push_back(&inp);
+    }
+  }
+  std::vector<CTPDigit> vrawdata;
+  for (auto const& coll : prerawdata) {
+    CTPDigit data;
+    data.mIntRecord = coll.first;
+    std::bitset<CTP_NINPUTS> inpmaskcoll = 0;
+    for (auto const inp : coll.second) {
+      switch (inp->mDetector) {
+        case o2::detectors::DetID::FT0: {
+          std::bitset<CTP_NINPUTS> inpmask = std::bitset<CTP_NINPUTS>(
+            (inp->mInputsMask & CTP_INPUTMASK_FT0.second).to_ullong());
+          inpmaskcoll |= inpmask << CTP_INPUTMASK_FT0.first;
+          break;
+        }
+        case o2::detectors::DetID::FV0: {
+          std::bitset<CTP_NINPUTS> inpmask = std::bitset<CTP_NINPUTS>(
+            (inp->mInputsMask & CTP_INPUTMASK_FT0.second).to_ullong());
+          inpmaskcoll |= inpmask << CTP_INPUTMASK_FT0.first;
+          break;
+        }
+        default:
+          // Error
+          LOG(ERROR) << "CTP Digitizer: unknown detector:" << inp->mDetector;
+          break;
+      }
+    }
+    data.mCTPInputMask = inpmaskcoll;
+    calculateClassMask(coll.second, data.mCTPClassMask);
+    vrawdata.emplace_back(data);
+  }
+  return std::move(vrawdata);
+}
+void Digitizer::calculateClassMask(std::vector<const CTPInputDigit*> inputs, std::bitset<CTP_NCLASSES>& classmask)
+{
+  // Example of Min Bias as V0 or T0
+  classmask = 0;
+  if (inputs.size() > 1) {
+    classmask = 1;
+  }
+}
+void Digitizer::init()
+{
+  LOG(INFO) << " @@@ CTP Digitizer::init. Nothing done. " << std::endl;
+}
diff --git a/Detectors/CTP/workflow/CMakeLists.txt b/Detectors/CTP/workflow/CMakeLists.txt
new file mode 100644
index 0000000000000..1aeb02e1ab208
--- /dev/null
+++ b/Detectors/CTP/workflow/CMakeLists.txt
@@ -0,0 +1,15 @@
+# Copyright CERN and copyright holders of ALICE O2. This software is distributed
+# under the terms of the GNU General Public License v3 (GPL Version 3), copied
+# verbatim in the file "COPYING".
+#
+# See http://alice-o2.web.cern.ch/license for full licensing information.
+#
+# In applying this license CERN does not waive the privileges and immunities
+# granted to it by virtue of its status as an Intergovernmental Organization or
+# submit itself to any jurisdiction.
+
+o2_add_library(CTPWorkflow
+               SOURCES src/CTPDigitWriterSpec.cxx
+               PUBLIC_LINK_LIBRARIES O2::Framework
+                                     O2::DataFormatsCTP
+                                     O2::DPLUtils)
\ No newline at end of file
diff --git a/Detectors/CTP/workflow/include/CTPWorkflow/CTPDigitWriterSpec.h b/Detectors/CTP/workflow/include/CTPWorkflow/CTPDigitWriterSpec.h
new file mode 100644
index 0000000000000..bf41c076e385b
--- /dev/null
+++ b/Detectors/CTP/workflow/include/CTPWorkflow/CTPDigitWriterSpec.h
@@ -0,0 +1,28 @@
+// Copyright CERN and copyright holders of ALICE O2. This software is
+// distributed under the terms of the GNU General Public License v3 (GPL
+// Version 3), copied verbatim in the file "COPYING".
+//
+// See http://alice-o2.web.cern.ch/license for full licensing information.
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#ifndef O2_CTPDIGITWRITERSPEC_H
+#define O2_CTPDIGITWRITERSPEC_H
+
+#include "Framework/DataProcessorSpec.h"
+#include "DPLUtils/MakeRootTreeWriterSpec.h"
+#include "Framework/InputSpec.h"
+#include "DataFormatsCTP/Digits.h"
+
+using namespace o2::framework;
+namespace o2
+{
+namespace ctp
+{
+framework::DataProcessorSpec getCTPDigitWriterSpec(bool raw = true);
+}
+} // namespace o2
+
+#endif //O2_CTPDIGITWRITERSPEC_H
diff --git a/Detectors/CTP/workflow/src/CTPDigitWriterSpec.cxx b/Detectors/CTP/workflow/src/CTPDigitWriterSpec.cxx
new file mode 100644
index 0000000000000..7b956954bfe79
--- /dev/null
+++ b/Detectors/CTP/workflow/src/CTPDigitWriterSpec.cxx
@@ -0,0 +1,35 @@
+// Copyright CERN and copyright holders of ALICE O2. This software is
+// distributed under the terms of the GNU General Public License v3 (GPL
+// Version 3), copied verbatim in the file "COPYING".
+//
+// See http://alice-o2.web.cern.ch/license for full licensing information.
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#include "CTPWorkflow/CTPDigitWriterSpec.h"
+
+namespace o2
+{
+namespace ctp
+{
+template <typename T>
+using BranchDefinition = framework::MakeRootTreeWriterSpec::BranchDefinition<T>;
+
+framework::DataProcessorSpec getCTPDigitWriterSpec(bool raw)
+{
+  using InputSpec = framework::InputSpec;
+  using MakeRootTreeWriterSpec = framework::MakeRootTreeWriterSpec;
+  // Spectators for logging
+  auto logger = [](std::vector<o2::ctp::CTPDigit> const& vecDigits) {
+    LOG(INFO) << "CTPDigitWriter pulled " << vecDigits.size() << " digits";
+  };
+  return MakeRootTreeWriterSpec(raw ? "ctp-digit-writer-dec" : "ctp-digit-writer",
+                                raw ? "o2_ctpdigits.root" : "ctpdigits.root",
+                                MakeRootTreeWriterSpec::TreeAttributes{"o2sim", "Tree with CTP digits"},
+                                BranchDefinition<std::vector<o2::ctp::CTPDigit>>{InputSpec{"digit", "CTP", "DIGITS", 0}, "CTPDigits", logger})();
+}
+
+} // namespace ctp
+} // namespace o2
diff --git a/Steer/DigitizerWorkflow/CMakeLists.txt b/Steer/DigitizerWorkflow/CMakeLists.txt
index ca2e6d516a84a..60a487738a5ce 100644
--- a/Steer/DigitizerWorkflow/CMakeLists.txt
+++ b/Steer/DigitizerWorkflow/CMakeLists.txt
@@ -12,6 +12,7 @@ o2_add_executable(digitizer-workflow
                   COMPONENT_NAME sim
                   SOURCES src/EMCALDigitWriterSpec.cxx
                           src/EMCALDigitizerSpec.cxx
+                          src/CTPDigitizerSpec.cxx
                           src/FT0DigitizerSpec.cxx
                           src/FV0DigitizerSpec.cxx
                           src/FDDDigitizerSpec.cxx
@@ -35,7 +36,9 @@ o2_add_executable(digitizer-workflow
                                         O2::FT0Simulation
                                         O2::FV0Simulation
                                         O2::FDDSimulation
-					O2::FDDWorkflow
+                                        O2::CTPSimulation
+                                        O2::CTPWorkflow
+                                        O2::FDDWorkflow
                                         O2::HMPIDSimulation
                                         O2::ITSMFTSimulation
                                         O2::ITSSimulation
@@ -62,7 +65,7 @@ o2_add_executable(digitizer-workflow
 o2_add_executable(mctruth-testworkflow
                   COMPONENT_NAME sim
                   SOURCES src/MCTruthTestWorkflow.cxx
-		          src/MCTruthSourceSpec.cxx
+	                  src/MCTruthSourceSpec.cxx
 	                  src/MCTruthWriterSpec.cxx
                   PUBLIC_LINK_LIBRARIES O2::Framework
                                         O2::SimulationDataFormat)
diff --git a/Steer/DigitizerWorkflow/src/CTPDigitizerSpec.cxx b/Steer/DigitizerWorkflow/src/CTPDigitizerSpec.cxx
new file mode 100644
index 0000000000000..198e7cc074810
--- /dev/null
+++ b/Steer/DigitizerWorkflow/src/CTPDigitizerSpec.cxx
@@ -0,0 +1,105 @@
+// Copyright CERN and copyright holders of ALICE O2. This software is
+// distributed under the terms of the GNU General Public License v3 (GPL
+// Version 3), copied verbatim in the file "COPYING".
+//
+// See http://alice-o2.web.cern.ch/license for full licensing information.
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#include "CTPDigitizerSpec.h"
+#include "Framework/ControlService.h"
+#include "Framework/ConfigParamRegistry.h"
+#include "Framework/DataProcessorSpec.h"
+#include "Framework//Task.h"
+#include "DetectorsBase/BaseDPLDigitizer.h"
+#include "DataFormatsCTP/Digits.h"
+#include "Steer/HitProcessingManager.h" // for DigitizationContext
+#include "DetectorsCommonDataFormats/DetID.h"
+#include "CTPSimulation/Digitizer.h"
+#include "DataFormatsFT0/Digit.h"
+#include "DataFormatsFV0/BCData.h"
+
+#include <TStopwatch.h>
+#include <gsl/span>
+
+using namespace o2::framework;
+namespace o2
+{
+namespace ctp
+{
+class CTPDPLDigitizerTask : public o2::base::BaseDPLDigitizer
+{
+  using GRP = o2::parameters::GRPObject;
+
+ public:
+  CTPDPLDigitizerTask() : o2::base::BaseDPLDigitizer(), mDigitizer() {}
+  ~CTPDPLDigitizerTask() override = default;
+  void initDigitizerTask(framework::InitContext& ic) override
+  {
+    mDigitizer.init();
+  }
+  void run(framework::ProcessingContext& pc)
+  {
+    // read collision context from input
+    //auto context = pc.inputs().get<o2::steer::DigitizationContext*>("collisioncontext");
+    //const bool withQED = context->isQEDProvided();
+    //auto& timesview = context->getEventRecords(withQED);
+    // read ctp inputs from input
+    auto ft0inputs = pc.inputs().get<gsl::span<o2::ft0::DetTrigInput>>("ft0");
+    auto fv0inputs = pc.inputs().get<gsl::span<o2::fv0::DetTrigInput>>("fv0");
+
+    // if there is nothing to do ... return
+    if ((ft0inputs.size() == 0) && (fv0inputs.size() == 0)) {
+      return;
+    }
+    std::vector<o2::ctp::CTPInputDigit> finputs;
+    TStopwatch timer;
+    timer.Start();
+    LOG(INFO) << "CALLING CTP DIGITIZATION";
+    for (const auto& inp : ft0inputs) {
+      CTPInputDigit finpdigit(inp.mIntRecord, inp.mInputs, o2::detectors::DetID::FT0);
+      finputs.emplace_back(finpdigit);
+    }
+    for (const auto& inp : fv0inputs) {
+      CTPInputDigit finpdigit(inp.mIntRecord, inp.mInputs, o2::detectors::DetID::FT0);
+      finputs.emplace_back(finpdigit);
+    }
+    gsl::span<CTPInputDigit> ginputs(finputs);
+    auto digits = mDigitizer.process(ginputs);
+    // send out to next stage
+    LOG(INFO) << "CTP DIGITS being sent.";
+    pc.outputs().snapshot(Output{"CTP", "DIGITS", 0, Lifetime::Timeframe}, digits);
+    LOG(INFO) << "CTP PRESENT being sent.";
+    pc.outputs().snapshot(Output{"CTP", "ROMode", 0, Lifetime::Timeframe}, mROMode);
+    timer.Stop();
+    LOG(INFO) << "CTP Digitization took " << timer.CpuTime() << "s";
+  }
+
+ protected:
+  o2::parameters::GRPObject::ROMode mROMode = o2::parameters::GRPObject::PRESENT;
+  o2::ctp::Digitizer mDigitizer; ///< Digitizer
+};
+o2::framework::DataProcessorSpec getCTPDigitizerSpec(int channel, std::vector<o2::detectors::DetID>& detList, bool mctruth)
+{
+  std::vector<InputSpec> inputs;
+  std::vector<OutputSpec> output;
+  if (std::find(detList.begin(), detList.end(), o2::detectors::DetID::FT0) != detList.end()) {
+    inputs.emplace_back("ft0", "FT0", "TRIGGERINPUT", 0, Lifetime::Timeframe);
+  }
+  if (std::find(detList.begin(), detList.end(), o2::detectors::DetID::FV0) != detList.end()) {
+    inputs.emplace_back("fv0", "FV0", "TRIGGERINPUT", 0, Lifetime::Timeframe);
+  }
+  output.emplace_back("CTP", "DIGITS", 0, Lifetime::Timeframe);
+  output.emplace_back("CTP", "ROMode", 0, Lifetime::Timeframe);
+  return DataProcessorSpec{
+    "CTPDigitizer",
+    inputs,
+    output,
+    AlgorithmSpec{adaptFromTask<CTPDPLDigitizerTask>()},
+    Options{{"pileup", VariantType::Int, 1, {"whether to run in continuous time mode"}},
+            {"disable-qed", o2::framework::VariantType::Bool, false, {"disable QED handling"}}}};
+}
+} // namespace ctp
+} // namespace o2
diff --git a/Steer/DigitizerWorkflow/src/CTPDigitizerSpec.h b/Steer/DigitizerWorkflow/src/CTPDigitizerSpec.h
new file mode 100644
index 0000000000000..ec54535616264
--- /dev/null
+++ b/Steer/DigitizerWorkflow/src/CTPDigitizerSpec.h
@@ -0,0 +1,27 @@
+// Copyright CERN and copyright holders of ALICE O2. This software is
+// distributed under the terms of the GNU General Public License v3 (GPL
+// Version 3), copied verbatim in the file "COPYING".
+//
+// See http://alice-o2.web.cern.ch/license for full licensing information.
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#ifndef STEER_DIGITIZERWORKFLOW_CTPDIGITIZER_H_
+#define STEER_DIGITIZERWORKFLOW_CTPDIGITIZER_H_
+
+#include "Framework/DataProcessorSpec.h"
+#include "DetectorsCommonDataFormats/DetID.h"
+
+namespace o2
+{
+namespace ctp
+{
+
+o2::framework::DataProcessorSpec getCTPDigitizerSpec(int channel, std::vector<o2::detectors::DetID>& detList, bool mctruth = true);
+
+} // namespace ctp
+} // end namespace o2
+
+#endif /* STEER_DIGITIZERWORKFLOW_CTPDIGITIZER_H_ */
diff --git a/Steer/DigitizerWorkflow/src/SimpleDigitizerWorkflow.cxx b/Steer/DigitizerWorkflow/src/SimpleDigitizerWorkflow.cxx
index ac7e755fd7eee..bc54b8c607584 100644
--- a/Steer/DigitizerWorkflow/src/SimpleDigitizerWorkflow.cxx
+++ b/Steer/DigitizerWorkflow/src/SimpleDigitizerWorkflow.cxx
@@ -43,6 +43,10 @@
 #include "FT0DigitizerSpec.h"
 #include "FT0DigitWriterSpec.h"
 
+// for CTP
+#include "CTPDigitizerSpec.h"
+#include "CTPWorkflow/CTPDigitWriterSpec.h"
+
 // for FV0
 #include "FV0DigitizerSpec.h"
 #include "FV0DigitWriterSpec.h"
@@ -593,7 +597,14 @@ WorkflowSpec defineDataProcessing(ConfigContext const& configcontext)
     // add PHOS writer
     specs.emplace_back(o2::cpv::getCPVDigitWriterSpec(mctruth));
   }
-
+  // the CTP part
+  if (isEnabled(o2::detectors::DetID::CTP)) {
+    detList.emplace_back(o2::detectors::DetID::CTP);
+    // connect the CTP digitization
+    specs.emplace_back(o2::ctp::getCTPDigitizerSpec(fanoutsize++, detList));
+    // connect the CTP digit writer
+    specs.emplace_back(o2::ctp::getCTPDigitWriterSpec(false));
+  }
   // GRP updater: must come after all detectors since requires their list
   specs.emplace_back(o2::parameters::getGRPUpdaterSpec(grpfile, detList));
 
diff --git a/macro/o2sim.C b/macro/o2sim.C
index f49086c474a36..45f51a45b94c1 100644
--- a/macro/o2sim.C
+++ b/macro/o2sim.C
@@ -150,6 +150,11 @@ FairRunSim* o2sim_init(bool asservice)
       }
       grp.addDetReadOut(o2::detectors::DetID(det->GetDetId()));
     }
+    // CTP is not a physical detector, just flag in the GRP if requested
+    if (isActivated("CTP")) {
+      grp.addDetReadOut(o2::detectors::DetID::CTP);
+    }
+
     grp.print();
     printf("VMC: %p\n", TVirtualMC::GetMC());
     auto field = dynamic_cast<o2::field::MagneticField*>(run->GetField());