diff --git a/pylgbst/__init__.py b/pylgbst/__init__.py
index 3a81ae6..8dc0e17 100644
--- a/pylgbst/__init__.py
+++ b/pylgbst/__init__.py
@@ -66,10 +66,10 @@ class MoveHub(object):
         Using https://github.com/JorgePe/BOOSTreveng/blob/master/Notifications.md
         """
         orig = data
-        log.debug("Notification on %s: %s", handle, str2hex(orig))
         data = data[3:]
+        log.debug("Notification on %s: %s", handle, str2hex(orig))
 
-        msg_type = ord(data[2])
+        msg_type = get_byte(data, 2)
 
         if msg_type == MSG_PORT_INFO:
             self._handle_port_info(data)
@@ -81,8 +81,8 @@ class MoveHub(object):
         pass
 
     def _handle_port_status(self, data):
-        port = ord(data[3])
-        status = ord(data[4])
+        port = get_byte(data, 3)
+        status = get_byte(data, 4)
 
         if status == STATUS_STARTED:
             self.devices[port].started()
@@ -94,8 +94,8 @@ class MoveHub(object):
             log.warning("Unhandled status value: 0x%x", status)
 
     def _handle_port_info(self, data):
-        port = ord(data[3])
-        dev_type = ord(data[5])
+        port = get_byte(data, 3)
+        dev_type = get_byte(data, 5)
 
         if port in PORTS and dev_type in DEVICE_TYPES:
             log.debug("Device %s at port %s", DEVICE_TYPES[dev_type], PORTS[port])
diff --git a/pylgbst/comms.py b/pylgbst/comms.py
index 5e05b6a..f017e9f 100644
--- a/pylgbst/comms.py
+++ b/pylgbst/comms.py
@@ -8,11 +8,10 @@ import sys
 import time
 import traceback
 from abc import abstractmethod
+from gattlib import DiscoveryService, GATTRequester
 from threading import Thread
 
-from gattlib import DiscoveryService, GATTRequester
-
-from pylgbst.constants import DEVICE_NAME, LEGO_MOVE_HUB
+from pylgbst.constants import LEGO_MOVE_HUB
 
 log = logging.getLogger('transport')
 
@@ -23,6 +22,10 @@ if sys.version_info[0] == 2:
 
     def hex2str(data):
         return data.decode("hex")
+
+
+    def get_byte(seq, index):
+        return ord(seq[index])
 else:
     import binascii
 
@@ -35,6 +38,10 @@ else:
         return binascii.unhexlify(data)
 
 
+    def get_byte(seq, index):
+        return seq[index]
+
+
 # noinspection PyMethodOverriding
 class Requester(GATTRequester):
     """
@@ -108,7 +115,7 @@ class BLEConnection(Connection):
             raise RuntimeError("No requester available")
 
     def read(self, handle):
-        # FIXME: repeating reads hang...
+        # FIXME: repeating reads hangs it...
         log.debug("Reading from: %s", handle)
         data = self.requester.read_by_handle(handle)
         log.debug("Result: %s", data)
diff --git a/pylgbst/constants.py b/pylgbst/constants.py
index f428aca..311a927 100644
--- a/pylgbst/constants.py
+++ b/pylgbst/constants.py
@@ -62,6 +62,7 @@ PORTS = {
 MSG_PORT_INFO = 0x04
 MSG_PORT_STATUS = 0x82
 MSG_SET_PORT_VAL = 0x81
+MSG_PORT_SUBSCRIBE = 0x41
 
 # NOTIFICATIONS
 TYPE_DISTANCE_COLOR_SENSOR = 0x25
diff --git a/pylgbst/peripherals.py b/pylgbst/peripherals.py
index baa042c..15960f8 100644
--- a/pylgbst/peripherals.py
+++ b/pylgbst/peripherals.py
@@ -15,11 +15,21 @@ class Peripheral(object):
         self.port = port
         self.working = False
 
-    def _set_port_val(self, value):
-        cmd = PACKET_VER + chr(MSG_SET_PORT_VAL) + chr(self.port)
-        cmd += value
+    def __repr__(self):
+        return "%s on port %s" % (self.__class__.__name__, PORTS[self.port] if self.port in PORTS else 'N/A')
 
-        self.parent.connection.write(MOVE_HUB_HARDWARE_HANDLE, chr(len(cmd)) + cmd)  # should we +1 cmd len here?
+    def _write_to_hub(self, msg_type, params):
+        cmd = PACKET_VER + chr(msg_type) + chr(self.port)
+        cmd += params
+        self.parent.connection.write(MOVE_HUB_HARDWARE_HANDLE, chr(len(cmd) + 1) + cmd)  # should we +1 cmd len here?
+
+    def _set_port_val(self, value):
+        # FIXME: became obsolete
+        self._write_to_hub(MSG_SET_PORT_VAL, value)
+
+    def _subscribe_on_port(self, params):
+        # FIXME: became obsolete
+        self._write_to_hub(MSG_PORT_SUBSCRIBE, params)
 
     def started(self):
         self.working = True
@@ -27,9 +37,6 @@ class Peripheral(object):
     def finished(self):
         self.working = False
 
-    def __repr__(self):
-        return "%s on port %s" % (self.__class__.__name__, PORTS[self.port] if self.port in PORTS else 'N/A')
-
 
 class LED(Peripheral):
     def set_color(self, color):
@@ -109,7 +116,9 @@ class ColorDistanceSensor(Peripheral):
 
 
 class TiltSensor(Peripheral):
-    pass
+    def subscribe(self, callback):
+        self._subscribe_on_port(params)
+        self._subscribers.append(callback)
 
 
 class Button(Peripheral):