exception handling while checksum check

__init__.py

@@ -428,7 +428,11 @@ class pure_json_protocol(object):
             return STATUS_OKAY, None
 
     def __check_frame_checksum__(self, frame):
-        return self.__calc_chksum__(frame[:-4]) == frame[-4:]
+        try:
+            return self.__calc_chksum__(frame[:-4]) == frame[-4:]
+        except TypeError:
+            logger.exception("Unable to check checksum")
+            return False
 
     def __clean_receive_buffer__(self):
         self.logger.debug("%s Cleaning up receive-buffer", self.__log_prefix__())