diff --git a/python/controller.py b/python/controller.py
new file mode 100644
index 0000000..f293210
--- /dev/null
+++ b/python/controller.py
@@ -0,0 +1,216 @@
+from threading import Thread
+from flask import Flask, jsonify, send_file
+from time import sleep
+from dataclasses import dataclass, field
+from datetime import datetime, timedelta
+import serial
+import uuid
+from collections import deque
+import sys
+import enum
+import struct
+import time
+
+from obus import Message, ModuleAddress
+
+
+INFO_ROUND_DURATION = timedelta(seconds=3)
+GAMESTATE_UPDATE_INTERVAL = timedelta(seconds=0.5)
+
+
+@enum.unique
+class Gamestate(enum.Enum):
+    INACTIVE = 0
+    INFO = 1
+    DISCOVER = 2
+    GAME = 3
+    GAMEOVER = 4
+
+
+
+@dataclass
+class PuzzleState:
+    '''State keeping object for puzzle and needy modules'''
+    strike_amount: int = 0
+    solved: bool = False
+
+
+@dataclass
+class SharedWebToSerial:
+    game_duration: timedelta = timedelta(seconds=60)
+    max_allowed_strikes: int = 3
+    seed: int = 0
+    blocked_modules: list[ModuleAddress] = field(default_factory=list)
+    start_game: bool = False
+    restart_game: bool = False
+
+
+@dataclass
+class SharedSerialToWeb:
+    gamestate: Gamestate = Gamestate.INACTIVE
+    info_round_start: datetime = None
+    discover_round_start: datetime = None
+    game_start: datetime = None
+    game_stop: datetime = None
+    last_state_update: datetime = None
+    registered_modules: dict[ModuleAddress, PuzzleState] = field(default_factory=dict)
+
+
+app = Flask(__name__)
+
+server_id = uuid.uuid4()
+print("Server ID: ", server_id)
+
+web_to_serial = SharedWebToSerial()
+serial_to_web = SharedSerialToWeb()
+
+
+def parse_can_line(ser) -> Message:
+    if not ser.in_waiting:
+        return None
+    line = ser.read(12)
+    if len(line) == 12:
+        if line == b'BEGIN START\n' or line[0] > 0b111:
+            return None
+        sender = (int(line[0]) << 8) + int(line[1])
+        size = int(line[2])
+        message = line[3:3+size]
+        return Message(message, sender, datetime.now())
+    return None
+
+
+def send_message(ser, msg) -> None:
+    # we send the payload padded with null-bytes, but these don't actually get sent
+    packed = struct.pack('>HB8s', msg.module_address().as_binary(), len(msg.payload), msg.payload)
+    ser.write(packed + b'\n')
+
+def calculate_puzzle_modules_left(serial_to_web) -> int:
+    return sum(address.is_puzzle() and not state.solved for address, state in serial_to_web.registered_modules.items())
+
+def calculate_strikes(serial_to_web) -> int:
+    return sum(state.strike_amount for state in serial_to_web.registered_modules.values())
+
+def serial_controller(serialport, web_to_serial, serial_to_web):
+    with serial.Serial(serialport, 115200, timeout=0.05) as ser:
+        serial_to_web.gamestate = Gamestate.INACTIVE
+        # TODO send message here to get all modules to stop talking and reset
+        ser.reset_input_buffer()
+        time.sleep(5)
+        while True:
+            if serial_to_web.gamestate == Gamestate.INACTIVE:
+                send_message(ser, Message.create_controller_infostart(web_to_serial.seed))
+                serial_to_web.gamestate = Gamestate.INFO
+                serial_to_web.info_round_start = datetime.now()
+                serial_to_web.registered_modules = {}
+            elif serial_to_web.gamestate == Gamestate.INFO:
+                parse_can_line(ser) # throw away, TODO keep this and display it
+                if datetime.now() - serial_to_web.info_round_start > INFO_ROUND_DURATION:
+                    serial_to_web.gamestate = Gamestate.DISCOVER
+                    send_message(ser, Message.create_controller_hello())
+            elif serial_to_web.gamestate == Gamestate.DISCOVER:
+                if web_to_serial.start_game:
+                    web_to_serial.start_game = False
+                    serial_to_web.game_start = datetime.now()
+                    serial_to_web.last_state_update = datetime.now()
+                    serial_to_web.gamestate = Gamestate.GAME
+                    send_message(ser, Message.create_controller_gamestart(web_to_serial.game_duration, 0, web_to_serial.max_allowed_strikes, len(serial_to_web.registered_modules)))
+                msg = parse_can_line(ser)
+                if msg is None:
+                    continue
+                puzzle_address = msg.get_puzzle_register()
+                if puzzle_address is None:
+                    continue
+                if puzzle_address in web_to_serial.blocked_modules:
+                    # this is blocked puzzle module, don't ack it
+                    continue
+                serial_to_web.registered_modules[puzzle_address] = PuzzleState()
+                send_message(ser, Message.create_controller_ack(msg.module_address()))
+
+            elif serial_to_web.gamestate == Gamestate.GAME:
+                # React to puzzle strike / solve
+                msg = parse_can_line(ser)
+                if msg is None:
+                    pass
+                elif (strike_details := msg.get_puzzle_strike_details()):
+                    strike_address, strike_amount = strike_details
+                    serial_to_web.registered_modules[strike_address].strike_amount = strike_amount
+                elif (solved_puzzle_address := msg.get_puzzle_solved()):
+                    serial_to_web.registered_modules[solved_puzzle_address].solved = True
+
+                # Handle strikeout / timeout / solve
+                time_left = web_to_serial.game_duration - (datetime.now() - serial_to_web.game_start)
+                puzzle_modules_left = calculate_puzzle_modules_left(serial_to_web)
+                total_strikes = calculate_strikes(serial_to_web)
+                if time_left.total_seconds() <= 0:
+                    # Pass zero timedelta, because time left can't be negative in the CAN protocol
+                    # Timeout case is also handled first, so that in other cases we know there's time left
+                    send_message(ser, Message.create_controller_timeout(timedelta(), puzzle_modules_left, web_to_serial.max_allowed_strikes, puzzle_modules_left))
+                    serial_to_web.gamestate = Gamestate.GAMEOVER
+                elif total_strikes > web_to_serial.max_allowed_strikes:
+                    send_message(ser, Message.create_controller_strikeout(time_left, puzzle_modules_left, web_to_serial.max_allowed_strikes, puzzle_modules_left))
+                    serial_to_web.gamestate = Gamestate.GAMEOVER
+                elif puzzle_modules_left == 0:
+                    send_message(ser, Message.create_controller_solved(time_left, puzzle_modules_left, web_to_serial.max_allowed_strikes, puzzle_modules_left))
+                    serial_to_web.gamestate = Gamestate.GAMEOVER
+                if serial_to_web.gamestate == Gamestate.GAMEOVER:
+                    serial_to_web.game_stop = datetime.now()
+                    continue
+
+                if datetime.now() - serial_to_web.last_state_update > GAMESTATE_UPDATE_INTERVAL:
+                    serial_to_web.last_state_update = datetime.now()
+                    # Send state update with known-good checked values
+                    send_message(ser, Message.create_controller_state(time_left, total_strikes, web_to_serial.max_allowed_strikes, puzzle_modules_left))
+
+            elif serial_to_web.gamestate == Gamestate.GAMEOVER:
+                if web_to_serial.restart_game:
+                    web_to_serial.restart_game = False
+                    serial_to_web.gamestate = Gamestate.INACTIVE
+
+
+
+@app.route('/status.json')
+def status():
+    status_dict = {
+        'gamestate': serial_to_web.gamestate.name
+    }
+    if serial_to_web.gamestate == Gamestate.GAME:
+        # Send the time left to avoid time syncronisation issues between server and client
+        # Client can then extrapolate if it wants to
+        status_dict['timeleft'] = (datetime.now() - serial_to_web.game_start).total_seconds()
+    elif serial_to_web.gamestate == Gamestate.GAMEOVER:
+        status_dict['timeleft'] = (serial_to_web.game_stop - serial_to_web.game_start).total_seconds()
+
+    if serial_to_web.gamestate in (Gamestate.DISCOVER, Gamestate.GAME, Gamestate.GAMEOVER):
+        status_dict['puzzles'] = [
+            {'address': address.to_binary(), 'solved': state.solved if address.is_puzzle() else None, 'strikes': state.strike_amount}
+            for address, state
+            in serial_to_web.registered_modules.items()
+        ]
+    return jsonify(status_dict)
+
+@app.route('/start')
+def start():
+    if serial_to_web.gamestate == Gamestate.DISCOVER:
+        web_to_serial.start_game = True
+        return 'OK'
+    return 'Wrong gamestage'
+
+@app.route('/restart')
+def restart():
+    if serial_to_web.gamestate == Gamestate.GAMEOVER:
+        web_to_serial.restart_game = True
+        return 'OK'
+    return 'Wrong gamestage'
+
+
+@app.route('/')
+def index():
+    return send_file('static/controller.html')
+
+if __name__ == '__main__':
+    if len(sys.argv) != 2:
+        print("Usage: python3 controller.py [serial port]")
+        sys.exit()
+    thread = Thread(target=serial_controller, args=(sys.argv[1], web_to_serial, serial_to_web))
+    thread.start()
+    app.run(debug=False, host='0.0.0.0', port=8080)
diff --git a/python/debugserver.py b/python/debugserver.py
index ce01074..f9c2261 100644
--- a/python/debugserver.py
+++ b/python/debugserver.py
@@ -24,8 +24,8 @@ max_message_cache = 200
 shared_data = SharedData(deque(maxlen=max_message_cache), -1)
 
 
-def serial_reader(shared_data):
-    with serial.Serial('/dev/ttyUSB0', 115200, timeout=0.05) as ser:
+def serial_reader(serialport, shared_data):
+    with serial.Serial(serialport, 115200, timeout=0.05) as ser:
         while True:
             line = ser.read(12)
             if not line:
@@ -55,6 +55,9 @@ def api(last_received):
         return jsonify({"server_id": server_id, "newest_msg": shared_data.last_message_index, "messages": list(shared_data.messages)[len(shared_data.messages) - (shared_data.last_message_index - last_received):]})
 
 if __name__ == '__main__':
-    thread = Thread(target=serial_reader, args=(shared_data, ))
+    if len(sys.argv) != 2:
+        print("Usage: python3 debugserver.py [serial port]")
+        sys.exit()
+    thread = Thread(target=serial_reader, args=(sys.argv[1], shared_data, ))
     thread.start()
     app.run(debug=False, host='0.0.0.0')
diff --git a/python/obus.py b/python/obus.py
index 823dd4a..8ac5554 100644
--- a/python/obus.py
+++ b/python/obus.py
@@ -1,5 +1,31 @@
 from dataclasses import dataclass
 from datetime import datetime
+import struct
+import enum
+from typing import NamedTuple
+
+
+@enum.unique
+class ControllerMessageType(enum.Enum):
+    ACK = 0
+    HELLO = 1
+    GAMESTART = 2
+    STATE = 3
+    SOLVED = 4
+    TIMEOUT = 5
+    STRIKEOUT = 6
+    INFOSTART = 7
+
+
+class ModuleAddress(NamedTuple):
+    module_type: int
+    identifier: int
+
+    def is_puzzle(self):
+        return self.module_type == 1
+
+    def as_binary(self):
+        return (self.module_type << 8) | self.identifier
 
 
 @dataclass
@@ -8,6 +34,67 @@ class Message:
     received_from: int
     received_at: datetime
 
+    @classmethod
+    def create_controller_message(cls, controller_message_type, content):
+        return cls(bytes([controller_message_type.value]) + content, 0, datetime.now())
+
+    @classmethod
+    def create_controller_infostart(cls, seed):
+        assert 0 <= seed <= 0xFFFFFFFF
+        return cls.create_controller_message(ControllerMessageType.INFOSTART, struct.pack('>L', seed))
+
+    @classmethod
+    def create_controller_ack(cls, module_address):
+        return cls.create_controller_message(ControllerMessageType.ACK, struct.pack('>H', module_address.as_binary()))
+
+    @classmethod
+    def create_controller_hello(cls):
+        return cls.create_controller_message(ControllerMessageType.HELLO, b'')
+
+    @classmethod
+    def create_controller_generic_stateupdate(cls, controller_message_type, timeleft, current_strikes, max_strikes, amount_puzzle_modules_left):
+        time_left_ms = int(timeleft.total_seconds() * 1000)
+        assert 0 <= time_left_ms <= 0xFFFFFFFF
+        return cls.create_controller_message(controller_message_type, struct.pack('>LBBB', time_left_ms, current_strikes, max_strikes, amount_puzzle_modules_left))
+
+    @classmethod
+    def create_controller_gamestart(cls, *args):
+        return cls.create_controller_generic_stateupdate(ControllerMessageType.GAMESTART, *args)
+
+    @classmethod
+    def create_controller_state(cls, *args):
+        return cls.create_controller_generic_stateupdate(ControllerMessageType.STATE, *args)
+
+    @classmethod
+    def create_controller_solved(cls, *args):
+        return cls.create_controller_generic_stateupdate(ControllerMessageType.SOLVED, *args)
+
+    @classmethod
+    def create_controller_timeout(cls, *args):
+        return cls.create_controller_generic_stateupdate(ControllerMessageType.TIMEOUT, *args)
+
+    @classmethod
+    def create_controller_strikeout(cls, *args):
+        return cls.create_controller_generic_stateupdate(ControllerMessageType.STRIKEOUT, *args)
+
+    def get_puzzle_register(self):
+        '''Returns the address of the puzzle if this is a register puzzle message, None otherwise'''
+        if self.sender_type() == 1 and self.payload[0] == 0:
+            return self.module_address()
+        return None
+
+    def get_puzzle_strike_details(self):
+        '''Returns the address and amount of strikes of the puzzle if this is a puzzle strike message, None otherwise'''
+        if self.sender_type() == 1 and self.payload[0] == 1:
+            return (self.module_address(), self.payload[1])
+        return None
+
+    def get_puzzle_solved(self):
+        '''Returns the address of the puzzle if this is a solved puzzle message, None otherwise'''
+        if self.sender_type() == 1 and self.payload[0] == 2:
+            return self.module_address()
+        return None
+
     def readable_time(self):
         return self.received_at.strftime('%H:%M:%S')
 
@@ -20,6 +107,9 @@ class Message:
     def sender_id(self):
         return (self.received_from >> 0) & 0b1111_1111
 
+    def module_address(self):
+        return ModuleAddress(self.sender_type(), self.sender_id())
+
     @staticmethod
     def human_readable_type(sender_type, sender_id):
         return [('controller' if sender_id == 0 else 'info'), 'puzzle', 'needy', 'RESERVED TYPE'][sender_type]
diff --git a/python/static/controller.html b/python/static/controller.html
new file mode 100644
index 0000000..f870a08
--- /dev/null
+++ b/python/static/controller.html
@@ -0,0 +1,14 @@
+<!doctype html>
+
+<html lang="en">
+<head>
+	<meta charset="utf-8">
+	<title>OBUS controller</title>
+</head>
+
+<body>
+	<button onclick="startbutton()">START</button>
+	<button onclick="restartbutton()">RESTART</button>
+	<script src="static/controller.js"></script>
+</body>
+</html>
diff --git a/python/static/controller.js b/python/static/controller.js
new file mode 100644
index 0000000..4155f67
--- /dev/null
+++ b/python/static/controller.js
@@ -0,0 +1,9 @@
+
+
+function startbutton() {
+	fetch('/start');
+}
+
+function restartbutton() {
+	fetch('/restart');
+}