diff --git a/Controll.py b/Controll.py
index 20273b8..855837a 100644
--- a/Controll.py
+++ b/Controll.py
@@ -14,6 +14,7 @@ startGUI()
 
 for i, serial in enumerate(serials):
     c = controllers[serial]
+    print(c)
     c.set_mode(0, pysmu.Mode.SIMV)  # CH A Hi-Z
     c.set_mode(1, pysmu.Mode.HI_Z)  # CH B Hi-Z
     MainWindow.add_list_item(MainWindow, serials[i], i, c.start, c.stop)
diff --git a/DeviceController.py b/DeviceController.py
index de4dcc4..6cb96be 100644
--- a/DeviceController.py
+++ b/DeviceController.py
@@ -68,7 +68,7 @@ class DeviceController:
 
     def writer_loop(self):
         ts0 = None
-        fn = os.path.join(OUTDIR, f"{time.strftime('%Y%m%d_%H%M%S')}_{self.dev.m_serial}.csv")
+        fn = os.path.join(OUTDIR, f"{time.strftime('%Y%m%d_%H%M%S')}_{self.dev.serial}.csv")
         with open(fn, "w", newline="") as f:
             w = csv.writer(f)
             w.writerow(["t_rel_s", "ch", "value"])
@@ -86,4 +86,4 @@ class DeviceController:
                     t_rel = (sample_idx + i) * 1e-5
                     w.writerow([t_rel, "B", v])
                 sample_idx += len(va)
-        print(f"[{self.dev.m_serial}] Datei geschlossen.")
\ No newline at end of file
+        print(f"[{self.dev.serial}] Datei geschlossen.")
\ No newline at end of file