diff --git a/lib/tdm_datamodel.hpp b/lib/tdm_datamodel.hpp
index 6ad172f..09c0f7a 100644
--- a/lib/tdm_datamodel.hpp
+++ b/lib/tdm_datamodel.hpp
@@ -53,6 +53,16 @@ struct block {
 
 // https://zone.ni.com/reference/de-XX/help/370858P-0113/tdmdatamodel/tdmdatamodel/tdm_header_tdx_data/
 
+enum class tdmdatatype {
+  eInt16Usi,
+  eInt32Usi,
+  eUInt8Usi,
+  eUInt16Usi,
+  eUInt32Usi,
+  eFloat32Usi,
+  eFloat64Usi
+};
+
 struct tdm_datatype {
 
   std::string name_;
diff --git a/lib/tdm_reaper.hpp b/lib/tdm_reaper.hpp
index 1561013..8a22b8b 100644
--- a/lib/tdm_reaper.hpp
+++ b/lib/tdm_reaper.hpp
@@ -76,6 +76,41 @@ class tdm_reaper
     return listofids;
   }
 
+public:
+
+  // check machine's datatypes
+  // https://en.cppreference.com/w/cpp/language/types
+  void check_local_datatypes()
+  {
+    std::cout<<"\nmachine's C++ datatypes:\n";
+    std::cout<<std::setw(25)<<std::left<<"char:"
+             <<std::setw(5)<<std::left<<sizeof(char)<<"byte(s)\n"
+             <<std::setw(25)<<std::left<<"uint8_t:"
+             <<std::setw(5)<<std::left<<sizeof(uint8_t)<<"byte(s)\n"
+
+             <<std::setw(25)<<std::left<<"short int:"
+             <<std::setw(5)<<std::left<<sizeof(short int)<<"byte(s)\n"
+             <<std::setw(25)<<std::left<<"unsigned short int:"
+             <<std::setw(5)<<std::left<<sizeof(unsigned short int)<<"byte(s)\n"
+
+             <<std::setw(25)<<std::left<<"int:"
+             <<std::setw(5)<<std::left<<sizeof(int)<<"byte(s)\n"
+             <<std::setw(25)<<std::left<<"unsigned int:"
+             <<std::setw(5)<<std::left<<sizeof(unsigned int)<<"byte(s)\n"
+
+             <<std::setw(25)<<std::left<<"long int:"
+             <<std::setw(5)<<std::left<<sizeof(long int)<<"byte(s)\n"
+             <<std::setw(25)<<std::left<<"unsigned long int:"
+             <<std::setw(5)<<std::left<<sizeof(unsigned long int)<<"byte(s)\n"
+
+             <<std::setw(25)<<std::left<<"float:"
+             <<std::setw(5)<<std::left<<sizeof(float)<<"byte(s)\n"
+             <<std::setw(25)<<std::left<<"double:"
+             <<std::setw(5)<<std::left<<sizeof(double)<<"byte(s)\n"
+             <<std::setw(25)<<std::left<<"long double:"
+             <<std::setw(5)<<std::left<<sizeof(long double)<<"byte(s)\n\n";
+  }
+
 public:
 
   // encoding
diff --git a/makefile b/makefile
index 5d12de5..2b16bfc 100644
--- a/makefile
+++ b/makefile
@@ -35,7 +35,7 @@ uninstall : $(INST)/$(EXE)
 	rm $<
 
 # build main.cpp object file and include git version/commit tag
-main.o : src/main.cpp
+main.o : src/main.cpp lib/$(SRC).hpp
 	@cp $< $<.cpp
 	@sed -i 's/TAGSTRING/$(GTAG)/g' $<.cpp
 	@sed -i 's/HASHSTRING/$(GHSH)/g' $<.cpp
diff --git a/src/main.cpp b/src/main.cpp
index 4cfef38..b707c94 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -185,6 +185,9 @@ int main(int argc, char* argv[])
                               + e.what() );
     }
 
+    // check available datatypes on machine
+    jack.check_local_datatypes();
+
     std::vector<std::string> chgrids = jack.get_channelgroup_ids();
     for ( auto el: chgrids ) std::cout<<el<<",";
     std::cout<<"\n\n";