diff --git a/redPoscdaq.py b/redPoscdaq.py
index 7d56c5307a052b49540af3537f5dc6ab4b33527f..a5155e1b9f03076c3fe87a03c63080243a495d74 100755
--- a/redPoscdaq.py
+++ b/redPoscdaq.py
@@ -1,11 +1,12 @@
 #!/usr/bin/env python3
-"""rpPoscdaq: fast data acquistion using the oscilloscope client of the MCPHA 
+"""redPoscdaq: fast data acquistion using the oscilloscope client of the MCPHA 
     application running on a RedPitaya FPGA board
 
-    When the network connection is established, the oscilloscope window
-    is activated in data-acquisition mode, i.e. restarted continously.
-
-    Optionally, triggered waveforms can be stored a file.
+    Contains a button to run the oscilloscope in daq mode, i.e. it is restarted 
+    continously. If defined, data is eported to a callback function. A callback
+    class redP_mimocorb() implements an interface to the daq rinbuffer mimoCoRB.      
+    Optionally, triggered waveforms can be stored a numpy binary file 
+    (.npy format).
 
     Code derived from mcpha.py by Pavel Demin  
 
@@ -13,6 +14,8 @@
     https://github.com/pavel-demin/red-pitaya-notes/releases/tag/20240204
 """
 
+script_name = 'redPoscidaq.py'
+
 # Communication with server process is achieved via command codes:
 #   command(code, number, data)  #    number typically is channel number
 #
@@ -49,10 +52,13 @@ import matplotlib
 from matplotlib.figure import Figure
 from multiprocessing import Event
 
-from npy_append_array import NpyAppendArray
-
 from mimocorb.buffer_control import rbPut
 
+# !!! for conditional import from npy_append_array !!!
+def import_npy_append_array():
+    global NpyAppendArray
+    from npy_append_array import NpyAppendArray
+
 from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
 from matplotlib.backends.backend_qt5agg import NavigationToolbar2QT as NavigationToolbar
 
@@ -115,7 +121,7 @@ class rpControl(QMainWindow, Ui_MCPHA):
         self.confd = {} if conf_dict is None else conf_dict
         self.parse_confd()
         # get configuration from command line
-        if conf_dict is None:
+        if os.path.split(sys.argv[0])[1]=='redPoscdaq.py':
              self.parse_args()
         self.callback = True if callback is not None else False
          
@@ -239,6 +245,8 @@ class rpControl(QMainWindow, Ui_MCPHA):
         self.trigger_slope = 0 if args.trigger_slope == 'rising' else 1
         # other parameters
         self.filename = args.file
+        if self.filename:
+            import_npy_append_array()
 
         
     def get_physical_units(self):