diff --git a/revpimodio2/helper.py b/revpimodio2/helper.py
index c0980c4..b256ff3 100644
--- a/revpimodio2/helper.py
+++ b/revpimodio2/helper.py
@@ -4,6 +4,7 @@ import queue
 import warnings
 from math import ceil
 from threading import Event, Lock, Thread
+from time import sleep
 from timeit import default_timer
 
 from revpimodio2 import BOTH, FALLING, RISING
@@ -602,8 +603,8 @@ class ProcimgWriter(Thread):
                                     self._eventq.put(tup_fire, False)
                                 del self.__dict_delay[tup_fire]
 
-                # Refresh abwarten
-                self._work.wait(self._adjwait)
+                # Sleep and not .wait (.wait uses system clock)
+                sleep(self._adjwait)
 
             # Wartezeit anpassen um echte self._refresh zu erreichen
             mrk_dt = default_timer()
diff --git a/revpimodio2/modio.py b/revpimodio2/modio.py
index ed1756d..31f93ba 100644
--- a/revpimodio2/modio.py
+++ b/revpimodio2/modio.py
@@ -678,7 +678,7 @@ class RevPiModIO(object):
         self._exit_level |= 2
         self.exit(full=True)
 
-    def cycleloop(self, func, cycletime=50):
+    def cycleloop(self, func, cycletime=50, blocking=True):
         """
         Startet den Cycleloop.
 
@@ -705,6 +705,7 @@ class RevPiModIO(object):
 
         :param func: Funktion, die ausgefuehrt werden soll
         :param cycletime: Zykluszeit in Millisekunden - Standardwert 50 ms
+        :param blocking: Wenn False, blockiert das Programm hier NICHT
         :return: None or the return value of the cycle function
         """
         # Prüfen ob ein Loop bereits läuft
@@ -726,6 +727,16 @@ class RevPiModIO(object):
                 "registered function '{0}' ist not callable".format(func)
             )
 
+        # Thread erstellen, wenn nicht blockieren soll
+        if not blocking:
+            self._th_mainloop = Thread(
+                target=self.cycleloop,
+                args=(func,),
+                kwargs={"cycletime": cycletime, "blocking": True}
+            )
+            self._th_mainloop.start()
+            return
+
         # Zykluszeit übernehmen
         old_cycletime = self._imgwriter.refresh
         if not cycletime == self._imgwriter.refresh:
@@ -777,11 +788,13 @@ class RevPiModIO(object):
         except Exception as ex:
             if self._imgwriter.lck_refresh.locked():
                 self._imgwriter.lck_refresh.release()
-            self.exit(full=False)
+            if self._th_mainloop is None:
+                self.exit(full=False)
             e = ex
         finally:
             # Cycleloop beenden
             self._looprunning = False
+            self._th_mainloop = None
 
         # Alte autorefresh Zeit setzen
         self._imgwriter.refresh = old_cycletime
diff --git a/setup.py b/setup.py
index a5e55c9..1b7c037 100644
--- a/setup.py
+++ b/setup.py
@@ -17,7 +17,7 @@ setup(
 
     license="LGPLv3",
     name="revpimodio2",
-    version="2.5.3e",
+    version="2.5.3f",
 
     packages=["revpimodio2"],
     python_requires="~=3.2",