diff --git a/stcgal/frontend.py b/stcgal/frontend.py
index 997ac45..6733bca 100644
--- a/stcgal/frontend.py
+++ b/stcgal/frontend.py
@@ -23,8 +23,18 @@
 import sys
 import argparse
 import stcgal
+import serial
 from stcgal.utils import BaudType
-from stcgal.protocols import *
+from stcgal.protocols import Stc89Protocol
+from stcgal.protocols import Stc12AProtocol
+from stcgal.protocols import Stc12BProtocol
+from stcgal.protocols import Stc12Protocol
+from stcgal.protocols import Stc15Protocol
+from stcgal.protocols import Stc15AProtocol
+from stcgal.protocols import StcUsb15Protocol
+from stcgal.protocols import StcAutoProtocol
+from stcgal.protocols import StcProtocolException
+from stcgal.protocols import StcFramingException
 from stcgal.ihex import IHex
 
 class StcGal:
diff --git a/stcgal/protocols.py b/stcgal/protocols.py
index 0d027ca..988f19b 100644
--- a/stcgal/protocols.py
+++ b/stcgal/protocols.py
@@ -27,17 +27,21 @@ import time
 import struct
 import re
 import errno
-import argparse
-import collections
 from stcgal.models import MCUModelDatabase
 from stcgal.utils import Utils
-from stcgal.options import Stc89Option, Stc12Option, Stc12AOption, Stc15Option, Stc15AOption
-from abc import ABC, abstractmethod
+from stcgal.options import Stc89Option
+from stcgal.options import Stc12Option
+from stcgal.options import Stc12AOption
+from stcgal.options import Stc15Option
+from stcgal.options import Stc15AOption
+from abc import ABC
+from abc import abstractmethod
 import functools
 import tqdm
 
 try:
-    import usb.core, usb.util
+    import usb.core
+    import usb.util
     _usb_available = True
 except ImportError:
     _usb_available = False