diff --git a/example/main.c b/example/main.c
index 7f72a06..d8ef635 100644
--- a/example/main.c
+++ b/example/main.c
@@ -44,8 +44,6 @@ set_blocking (int fd, int should_block)
 static shellmatta_retCode_t doSomething(shellmatta_handle_t handle, const char *arguments, uint32_t length)
 {
 
-    //shellmatta_printf(handle, "blubb\n\r");
-
     return SHELLMATTA_OK;
 }
 shellmatta_cmd_t doSomethingCmd = {"doSomething", "do", "Function does something", "use me, please", doSomething, NULL};
@@ -53,7 +51,6 @@ shellmatta_cmd_t doSomethingCmd = {"doSomething", "do", "Function does something
 static shellmatta_retCode_t doSome(shellmatta_handle_t handle, const char *arguments, uint32_t length)
 {
 
-    //shellmatta_printf(handle, "blubb\n\r");
     shellmatta_write(handle, "blubb\r\n", 7u);
 
     return SHELLMATTA_OK;
@@ -63,9 +60,6 @@ shellmatta_cmd_t doSomeCmd = {"adoSome2", "adof2", "Function does something", "u
 
 static shellmatta_retCode_t quit(shellmatta_handle_t handle, const char *arguments, uint32_t length)
 {
-
-    //shellmatta_printf(handle, "Bye\n\r");
-
     exitRequest = true;
 
     return SHELLMATTA_OK;
@@ -75,13 +69,7 @@ shellmatta_cmd_t quitCommand = {"quit", "q", "Function quits the shell", "", qui
 
 shellmatta_retCode_t writeFct(const char* data, uint32_t length)
 {
-//    for(uint32_t i = 0u; i < length; i ++)
-//    {
-        write(f, data, length);
-        //printf("%c", data[i]);
-//    }
-
-    //fflush(stdout);
+    write(f, data, length);
 
     return SHELLMATTA_OK;
 }
@@ -92,11 +80,7 @@ int main(void)
     static char historyBuffer[4096];
     static shellmatta_instance_t instance;
 
-//    initscr();
-//    raw();
-//    keypad(stdscr, TRUE);
-//    noecho();
-    f = open("/dev/pts/2", O_RDWR | O_SYNC);
+    f = open("/dev/pts/3", O_RDWR | O_SYNC);
 
     if (f < 0)
     {
@@ -115,9 +99,9 @@ int main(void)
                         "shellmatta->",
                         NULL,
                         writeFct);
-    shellmatta_addCmd(&instance, &doSomethingCmd);
-    shellmatta_addCmd(&instance, &doSomeCmd);
-    shellmatta_addCmd(&instance, &quitCommand);
+    shellmatta_addCmd(handle, &doSomethingCmd);
+    shellmatta_addCmd(handle, &doSomeCmd);
+    shellmatta_addCmd(handle, &quitCommand);
 
     while(exitRequest == false)
     {
@@ -129,11 +113,9 @@ int main(void)
         fprintf(stdout, "0x%02x \n", c);
         fflush(stdout);
 
-        shellmatta_processData(&instance, &c, res);
+        shellmatta_processData(handle, &c, res);
     }
 
-//    refresh();
-//    endwin();
     close(f);
 
     return 0;
diff --git a/makefile b/makefile
index 4a2804a..73ee68f 100644
--- a/makefile
+++ b/makefile
@@ -20,18 +20,23 @@ SOURCES :=  src/shellmatta.c                \
             
 INCLUDES    := api .
 
-TEST_SOURCES := test/test_main.cpp                                      \
-                test/shellmatta_utils/test_utils_writeEcho.cpp          \
-                test/shellmatta_utils/test_utils_shellItoa.cpp          \
-                test/shellmatta_utils/test_utils_saveCursorPos.cpp      \
-                test/shellmatta_utils/test_utils_restoreCursorPos.cpp   \
-                test/shellmatta_utils/test_utils_eraseLine.cpp          \
-                test/shellmatta_utils/test_utils_rewindCursor.cpp       \
-                test/shellmatta_utils/test_utils_forwardCursor.cpp      \
-                test/shellmatta_utils/test_utils_clearInput.cpp         \
-                test/shellmatta_utils/test_utils_insertChars.cpp
+UNITTEST_SOURCES := test/unittest/test_main.cpp                                    \
+                    test/unittest/shellmatta_utils/test_utils_writeEcho.cpp        \
+                    test/unittest/shellmatta_utils/test_utils_shellItoa.cpp        \
+                    test/unittest/shellmatta_utils/test_utils_saveCursorPos.cpp    \
+                    test/unittest/shellmatta_utils/test_utils_restoreCursorPos.cpp \
+                    test/unittest/shellmatta_utils/test_utils_eraseLine.cpp        \
+                    test/unittest/shellmatta_utils/test_utils_rewindCursor.cpp     \
+                    test/unittest/shellmatta_utils/test_utils_forwardCursor.cpp    \
+                    test/unittest/shellmatta_utils/test_utils_clearInput.cpp       \
+                    test/unittest/shellmatta_utils/test_utils_insertChars.cpp
 
-TEST_CPPOBJ  := $(patsubst %.cpp,$(OBJ_DIR)%.o,$(TEST_SOURCES))
+INTEGRATIONTEST_SOURCES :=  test/integrationtest/test_main.cpp          \
+                            test/integrationtest/test_integration.cpp
+
+UNITTEST_CPPOBJ  := $(patsubst %.cpp,$(OBJ_DIR)%.o,$(UNITTEST_SOURCES))
+
+INTEGRATIONTEST_CPPOBJ  := $(patsubst %.cpp,$(OBJ_DIR)%.o,$(INTEGRATIONTEST_SOURCES))
 
 CFLAGS      := $(INCLUDES:%=-I%) -g
 TESTFLAGS   := $(INCLUDES:%=-I%) -g -fprofile-arcs -ftest-coverage
@@ -46,9 +51,11 @@ EXAMPLE_COBJ     := $(patsubst %.c,$(OBJ_DIR)%.o,$(EXAMPLE_SOURCES))
 
 EXAMPLE_TARGET  := $(OBJ_DIR)example/example
 
-TEST_TARGET     := $(OBJ_DIR)test/test
+UNITTEST_TARGET     := $(OBJ_DIR)test/unittest/unittest
 
-OBJ     := $(COBJ) $(EXAMPLE_COBJ) $(TEST_CPPOBJ)
+INTEGRATIONTEST_TARGET     := $(OBJ_DIR)test/integrationtest/integrationtest
+
+OBJ     := $(COBJ) $(EXAMPLE_COBJ) $(UNITTEST_CPPOBJ) $(INTEGRATIONTEST_CPPOBJ)
 DEPS    := $(OBJ:%.o=%.d)
 
 export
@@ -60,14 +67,24 @@ help:
 	@echo example   - build example
 	@echo -------------------------
 
-test: $(TEST_TARGET)
-	- @mkdir -p output/test/report
-	@echo running test:
-	-output/test/test
-	#gcov -o output/test $(TEST_CPPOBJ) -r
-	gcovr --html-details --output output/test/report/report.html output/test -f src -f api
-	#-rm *.gcov
+test: unittest integrationtest
 
+unittest: $(UNITTEST_TARGET)
+	- @mkdir -p output/test/unittest/report
+	@echo running test:
+	-$(UNITTEST_TARGET)
+	#gcov -o output/test $(TEST_CPPOBJ) -r
+	gcovr --html-details --output $(OBJ_DIR)test/unittest/report/report.html output/test/unittest -f src -f api
+	#-rm *.gcov
+	
+integrationtest: $(INTEGRATIONTEST_TARGET)
+	- @mkdir -p output/test/integrationtest/report
+	@echo running test:
+	-$(INTEGRATIONTEST_TARGET)
+	#gcov -o output/test $(TEST_CPPOBJ) -r
+	gcovr --html-details --output $(OBJ_DIR)test/integrationtest/report/report.html output/test/integrationtest -f src -f api
+	#-rm *.gcov
+	
 example: $(EXAMPLE_TARGET)
 	@echo building example
 
@@ -83,7 +100,11 @@ $(EXAMPLE_TARGET): $(COBJ) $(EXAMPLE_COBJ)
 	- @mkdir -p $(@D)
 	$(CC) $(LFLAGS) $(LIB_PATH) -o $@ $^ $(LIBS)
 
-$(TEST_TARGET): $(TEST_CPPOBJ)
+$(UNITTEST_TARGET): $(UNITTEST_CPPOBJ)
+	- @mkdir -p $(@D)
+	$(CPP) $(TESTLFLAGS) $(LIB_PATH) -o $@ $^ $(LIBS)
+	
+$(INTEGRATIONTEST_TARGET): $(INTEGRATIONTEST_CPPOBJ) $(COBJ)
 	- @mkdir -p $(@D)
 	$(CPP) $(TESTLFLAGS) $(LIB_PATH) -o $@ $^ $(LIBS)
 
@@ -101,7 +122,7 @@ $(EXAMPLE_COBJ):
 	@$(CC) -c $(CFLAGS) $(DEPEND) -o $@  $(subst $(OBJ_DIR), ,$(@:%.o=%.c))
 	$(CC) -c $(CFLAGS) -o $@  $(subst $(OBJ_DIR), ,$(@:%.o=%.c))
 
-$(TEST_CPPOBJ):
+$(UNITTEST_CPPOBJ) $(INTEGRATIONTEST_CPPOBJ):
 	- @mkdir -p $(@D)
 	@$(CPP) -c $(TESTFLAGS) $(DEPEND) -o $@  $(subst $(OBJ_DIR), ,$(@:%.o=%.cpp))
 	$(CPP) -c $(TESTFLAGS) -o $@  $(subst $(OBJ_DIR), ,$(@:%.o=%.cpp))
diff --git a/test/integrationtest/test_integration.cpp b/test/integrationtest/test_integration.cpp
new file mode 100644
index 0000000..2d19751
--- /dev/null
+++ b/test/integrationtest/test_integration.cpp
@@ -0,0 +1,122 @@
+#include "test/framework/catch.hpp"
+extern "C" {
+#include "shellmatta.h"
+}
+#include <string.h>
+
+static uint32_t write_callCnt = 0u;
+static char write_data[1024];
+static uint32_t write_length;
+
+static shellmatta_retCode_t writeFct(const char* data, uint32_t length)
+{
+    write_callCnt ++;
+    while((length > 0) && (write_length < sizeof(write_data)))
+    {
+        write_data[write_length] = *data;
+        data ++;
+        length --;
+        write_length ++;
+    }
+
+    return SHELLMATTA_OK;
+}
+
+static shellmatta_retCode_t doSomething(shellmatta_handle_t handle, const char *arguments, uint32_t length)
+{
+
+    return SHELLMATTA_OK;
+}
+shellmatta_cmd_t doSomethingCmd = {"doSomething", "do", "Function does something", "use me, please", doSomething, NULL};
+
+
+TEST_CASE( "shellmatta empty function" ) {
+
+    shellmatta_instance_t inst;
+    shellmatta_handle_t handle;
+    char buffer[1024];
+    char historyBuffer[1024];
+    char *dummyData =   "\r\nshellmatta->";
+
+    shellmatta_doInit(  &inst,
+                        &handle,
+                        buffer,
+                        sizeof(buffer),
+                        historyBuffer,
+                        sizeof(historyBuffer),
+                        "shellmatta->",
+                        NULL,
+                        writeFct);
+
+    write_callCnt = 0u;
+    memset(write_data, 0, sizeof(write_data));
+    write_length = 0u;
+
+    shellmatta_processData(handle, "\r", 1);
+
+    CHECK( write_length == 14u);
+    REQUIRE( strcmp(dummyData, write_data) == 0);
+
+}
+
+TEST_CASE( "shellmatta help function" ) {
+
+    shellmatta_instance_t inst;
+    shellmatta_handle_t handle;
+    char buffer[1024];
+    char historyBuffer[1024];
+    char *dummyData =   "h\r\n"
+                        "doSomething  do  Function does something  use me, please\r\n"
+                        "help         h   Print this help text     help\r\n"
+                        "\r\nshellmatta->";
+
+    shellmatta_doInit(  &inst,
+                        &handle,
+                        buffer,
+                        sizeof(buffer),
+                        historyBuffer,
+                        sizeof(historyBuffer),
+                        "shellmatta->",
+                        NULL,
+                        writeFct);
+    shellmatta_addCmd(handle, &doSomethingCmd);
+
+    write_callCnt = 0u;
+    memset(write_data, 0, sizeof(write_data));
+    write_length = 0u;
+
+    shellmatta_processData(handle, "h\r", 2);
+
+    CHECK( write_length == 123u);
+    CHECK( strcmp(dummyData, write_data) == 0);
+
+
+    write_callCnt = 0u;
+    memset(write_data, 0, sizeof(write_data));
+    write_length = 0u;
+
+    dummyData =     "h 564 321 56 465 46\r\n"
+                    "doSomething  do  Function does something  use me, please\r\n"
+                    "help         h   Print this help text     help\r\n"
+                    "\r\nshellmatta->";
+
+    shellmatta_processData(handle, "h 564 321 56 465 46\r", 20);
+
+    CHECK( write_length == 141u);
+    CHECK( strcmp(dummyData, write_data) == 0);
+
+
+    write_callCnt = 0u;
+    memset(write_data, 0, sizeof(write_data));
+    write_length = 0u;
+
+    dummyData = "hr\r\n"
+                "Command: hr not found"
+                "\r\nshellmatta->";
+
+    shellmatta_processData(handle, "hr\r", 3);
+
+    CHECK( write_length == 39u);
+    REQUIRE( strcmp(dummyData, write_data) == 0);
+}
+
diff --git a/test/test_main.cpp b/test/integrationtest/test_main.cpp
similarity index 68%
rename from test/test_main.cpp
rename to test/integrationtest/test_main.cpp
index baa411f..ea7b737 100644
--- a/test/test_main.cpp
+++ b/test/integrationtest/test_main.cpp
@@ -3,5 +3,5 @@
 // Let Catch provide main():
 #define CATCH_CONFIG_MAIN
 
-#include "framework/catch.hpp"
+#include "test/framework/catch.hpp"
 
diff --git a/test/shellmatta_utils/test_utils_clearInput.cpp b/test/unittest/shellmatta_utils/test_utils_clearInput.cpp
similarity index 100%
rename from test/shellmatta_utils/test_utils_clearInput.cpp
rename to test/unittest/shellmatta_utils/test_utils_clearInput.cpp
diff --git a/test/shellmatta_utils/test_utils_eraseLine.cpp b/test/unittest/shellmatta_utils/test_utils_eraseLine.cpp
similarity index 100%
rename from test/shellmatta_utils/test_utils_eraseLine.cpp
rename to test/unittest/shellmatta_utils/test_utils_eraseLine.cpp
diff --git a/test/shellmatta_utils/test_utils_forwardCursor.cpp b/test/unittest/shellmatta_utils/test_utils_forwardCursor.cpp
similarity index 100%
rename from test/shellmatta_utils/test_utils_forwardCursor.cpp
rename to test/unittest/shellmatta_utils/test_utils_forwardCursor.cpp
diff --git a/test/shellmatta_utils/test_utils_insertChars.cpp b/test/unittest/shellmatta_utils/test_utils_insertChars.cpp
similarity index 100%
rename from test/shellmatta_utils/test_utils_insertChars.cpp
rename to test/unittest/shellmatta_utils/test_utils_insertChars.cpp
diff --git a/test/shellmatta_utils/test_utils_restoreCursorPos.cpp b/test/unittest/shellmatta_utils/test_utils_restoreCursorPos.cpp
similarity index 100%
rename from test/shellmatta_utils/test_utils_restoreCursorPos.cpp
rename to test/unittest/shellmatta_utils/test_utils_restoreCursorPos.cpp
diff --git a/test/shellmatta_utils/test_utils_rewindCursor.cpp b/test/unittest/shellmatta_utils/test_utils_rewindCursor.cpp
similarity index 100%
rename from test/shellmatta_utils/test_utils_rewindCursor.cpp
rename to test/unittest/shellmatta_utils/test_utils_rewindCursor.cpp
diff --git a/test/shellmatta_utils/test_utils_saveCursorPos.cpp b/test/unittest/shellmatta_utils/test_utils_saveCursorPos.cpp
similarity index 100%
rename from test/shellmatta_utils/test_utils_saveCursorPos.cpp
rename to test/unittest/shellmatta_utils/test_utils_saveCursorPos.cpp
diff --git a/test/shellmatta_utils/test_utils_shellItoa.cpp b/test/unittest/shellmatta_utils/test_utils_shellItoa.cpp
similarity index 100%
rename from test/shellmatta_utils/test_utils_shellItoa.cpp
rename to test/unittest/shellmatta_utils/test_utils_shellItoa.cpp
diff --git a/test/shellmatta_utils/test_utils_writeEcho.cpp b/test/unittest/shellmatta_utils/test_utils_writeEcho.cpp
similarity index 100%
rename from test/shellmatta_utils/test_utils_writeEcho.cpp
rename to test/unittest/shellmatta_utils/test_utils_writeEcho.cpp
diff --git a/test/unittest/test_main.cpp b/test/unittest/test_main.cpp
new file mode 100644
index 0000000..ea7b737
--- /dev/null
+++ b/test/unittest/test_main.cpp
@@ -0,0 +1,7 @@
+// 010-TestCase.cpp
+
+// Let Catch provide main():
+#define CATCH_CONFIG_MAIN
+
+#include "test/framework/catch.hpp"
+