diff --git a/.idea/misc.xml b/.idea/misc.xml
index 3999087..bc8d735 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -4,4 +4,7 @@
     <option name="languageLevel" value="ES6" />
   </component>
   <component name="ProjectRootManager" version="2" project-jdk-name="Python 3.6" project-jdk-type="Python SDK" />
+  <component name="PythonCompatibilityInspectionAdvertiser">
+    <option name="version" value="3" />
+  </component>
 </project>
\ No newline at end of file
diff --git a/revpimodio2/__init__.py b/revpimodio2/__init__.py
index 5b1089d..708b616 100644
--- a/revpimodio2/__init__.py
+++ b/revpimodio2/__init__.py
@@ -13,7 +13,7 @@ Auf alle IOs kann der Benutzer Funktionen als Events registrieren. Diese
 fuehrt das Modul bei Datenaenderung aus.
 """
 __all__ = [
-    "RevPiModIO", "RevPiModIODriver", "RevPiModIOSelected",
+    "RevPiModIO", "RevPiModIODriver", "RevPiModIOSelected", "run_plc",
     "RevPiNetIO", "RevPiNetIODriver", "RevPiNetIOSelected",
     "Cycletools", "EventCallback"
 ]
@@ -21,7 +21,7 @@ __author__ = "Sven Sager <akira@revpimodio.org>"
 __copyright__ = "Copyright (C) 2018 Sven Sager"
 __license__ = "LGPLv3"
 __name__ = "revpimodio2"
-__version__ = "2.4.5c"
+__version__ = "2.5.0"
 
 # Global package values
 OFF = 0
@@ -95,5 +95,5 @@ def consttostr(value) -> str:
 
 # Benötigte Klassen importieren
 from .helper import Cycletools, EventCallback
-from .modio import RevPiModIO, RevPiModIODriver, RevPiModIOSelected
+from .modio import RevPiModIO, RevPiModIODriver, RevPiModIOSelected, run_plc
 from .netio import RevPiNetIO, RevPiNetIODriver, RevPiNetIOSelected
diff --git a/revpimodio2/device.py b/revpimodio2/device.py
index 08092e8..c6475a4 100644
--- a/revpimodio2/device.py
+++ b/revpimodio2/device.py
@@ -1254,7 +1254,7 @@ class Virtual(Gateway):
         for io in self.get_inputs():
             self._ba_devdata[io._slc_address] = io._defaultvalue
 
-        # Outputs auf Bus schreiben
+        # Inputs auf Bus schreiben
         self._modio._myfh_lck.acquire()
         try:
             self._modio._myfh.seek(self._slc_inpoff.start)
diff --git a/revpimodio2/helper.py b/revpimodio2/helper.py
index 1b93ece..ae04d68 100644
--- a/revpimodio2/helper.py
+++ b/revpimodio2/helper.py
@@ -86,9 +86,10 @@ class Cycletools:
     """
 
     __slots__ = "__cycle", "__cycletime", "__ucycle", "__dict_ton", \
-                "__dict_tof", "__dict_tp", "_start_timer", "core", "first", \
-                "io", "last", "flag1c", "flag5c", "flag10c", "flag15c", \
-                "flag20c", "flank5c", "flank10c", "flank15c", "flank20c", "var"
+                "__dict_tof", "__dict_tp", "_start_timer", "core", "device", \
+                "first", "io", "last", "var", \
+                "flag1c", "flag5c", "flag10c", "flag15c", "flag20c", \
+                "flank5c", "flank10c", "flank15c", "flank20c"
 
     def __init__(self, cycletime, revpi_object):
         """Init Cycletools class."""
@@ -102,6 +103,7 @@ class Cycletools:
 
         # Access to core and io
         self.core = revpi_object.core
+        self.device = revpi_object.device
         self.io = revpi_object.io
 
         # Taktmerker
@@ -476,6 +478,7 @@ class ProcimgWriter(Thread):
         mrk_warn = True
         mrk_dt = default_timer()
 
+        bytesbuff = bytearray(self._modio._length)
         while not self._work.is_set():
             ot = mrk_dt
 
@@ -491,7 +494,7 @@ class ProcimgWriter(Thread):
 
             try:
                 fh.seek(0)
-                bytesbuff = bytearray(fh.read(self._modio._length))
+                fh.readinto(bytesbuff)
 
                 if self._modio._monitoring or self._modio._direct_output:
                     # Inputs und Outputs in Puffer
diff --git a/revpimodio2/io.py b/revpimodio2/io.py
index 8ac2f45..fadeaec 100644
--- a/revpimodio2/io.py
+++ b/revpimodio2/io.py
@@ -4,7 +4,7 @@ import struct
 from re import match as rematch
 from threading import Event
 
-from revpimodio2 import BOTH, FALLING, INP, MEM, RISING, consttostr
+from revpimodio2 import BOTH, FALLING, INP, MEM, OUT, RISING, consttostr
 
 __author__ = "Sven Sager"
 __copyright__ = "Copyright (C) 2018 Sven Sager"
@@ -291,7 +291,7 @@ class IOBase(object):
     __slots__ = "__bit_ioctl_off", "__bit_ioctl_on", "_bitaddress", \
                 "_bitshift", "_bitlength", "_byteorder", "_defaultvalue", \
                 "_iotype", "_length", "_name", "_parentdevice", \
-                "_signed", "_slc_address", "bmk", "export"
+                "_read_only_io", "_signed", "_slc_address", "bmk", "export"
 
     def __init__(self, parentdevice, valuelist: list, iotype: int, byteorder: str, signed: bool):
         """
@@ -318,6 +318,7 @@ class IOBase(object):
 
         self.__bit_ioctl_off = None
         self.__bit_ioctl_on = None
+        self._read_only_io = iotype != OUT
         self._byteorder = byteorder
         self._iotype = iotype
         self._name = valuelist[0]
@@ -576,19 +577,23 @@ class IOBase(object):
 
         :param value: IO-Wert als <class bytes'> oder <class 'bool'>
         """
-        if self._iotype == INP:
-            if self._parentdevice._modio._simulator:
+        if self._read_only_io:
+            if self._iotype == INP:
+                if self._parentdevice._modio._simulator:
+                    raise RuntimeError(
+                        "can not write to output '{0}' in simulator mode"
+                        "".format(self._name)
+                    )
+                else:
+                    raise RuntimeError(
+                        "can not write to input '{0}'".format(self._name)
+                    )
+            elif self._iotype == MEM:
                 raise RuntimeError(
-                    "can not write to output '{0}' in simulator mode"
-                    "".format(self._name)
+                    "can not write to memory '{0}'".format(self._name)
                 )
-            else:
-                raise RuntimeError(
-                    "can not write to input '{0}'".format(self._name)
-                )
-        if self._iotype == MEM:
             raise RuntimeError(
-                "can not write to memory '{0}'".format(self._name)
+                "the io object '{0}' is read only".format(self._name)
             )
 
         if self._bitshift:
diff --git a/revpimodio2/modio.py b/revpimodio2/modio.py
index 75ef4b7..8a7dda7 100644
--- a/revpimodio2/modio.py
+++ b/revpimodio2/modio.py
@@ -1336,6 +1336,29 @@ class RevPiModIODriver(RevPiModIOSelected):
         )
 
 
+def run_plc(func, cycletime=50, replace_io_file=None):
+    """
+    Run Revoluton Pi as real plc with cycle loop and exclusive IO access.
+
+    This function is just a shortcut to run the module in cycle loop mode and
+    handle the program exit signal. You will access the .io, .core, .device
+    via the cycletools in your cycle function.
+
+    Shortcut vor this source code:
+        rpi = RevPiModIO(autorefresh=True, replace_io_file=replace_io_file)
+        rpi.handlesignalend()
+        return rpi.cycleloop(func, cycletime)
+
+    :param func: Function to run every set milliseconds
+    :param cycletime: Cycle time in milliseconds
+    :param replace_io_file: Load replace IO configuration from file
+    :return: None or the return value of the cycle function
+    """
+    rpi = RevPiModIO(autorefresh=True, replace_io_file=replace_io_file)
+    rpi.handlesignalend()
+    return rpi.cycleloop(func, cycletime)
+
+
 # Nachträglicher Import
 from . import app as appmodule
 from . import device as devicemodule
diff --git a/setup.py b/setup.py
index 10c68e1..89e4ece 100644
--- a/setup.py
+++ b/setup.py
@@ -17,7 +17,7 @@ setup(
 
     license="LGPLv3",
     name="revpimodio2",
-    version="2.4.5d",
+    version="2.5.0",
 
     packages=["revpimodio2"],
     python_requires="~=3.2",