diff --git a/controller/Hamnet70Controller.py b/controller/Hamnet70Controller.py
new file mode 100755
index 0000000..0f73e46
--- /dev/null
+++ b/controller/Hamnet70Controller.py
@@ -0,0 +1,130 @@
+#!/usr/bin/env python2
+
+import fcntl
+import struct
+import os
+import socket
+import threading
+from select import select
+import sys
+
+import logging as log
+
+sys.path.append(os.environ.get('GRC_HIER_PATH', os.path.expanduser('~/.grc_gnuradio')))
+from hamnet70_demod import hamnet70_demod  # grc-generated hier_block
+from hamnet70_mod import hamnet70_mod  # grc-generated hier_block
+
+import pmt
+from gnuradio import gr
+from gnuradio import blocks
+
+import numpy as np
+
+TUNSETIFF = 0x400454ca
+TUNSETOWNER = TUNSETIFF + 2
+IFF_TUN = 0x0001
+IFF_TAP = 0x0002
+IFF_NO_PI = 0x1000
+
+
+class Hamnet70Controller(gr.basic_block):
+    def _tuntap_setup(self):
+        tun = open('/dev/net/tun', 'r+b', buffering=0)
+        ifr = struct.pack('16sH', self._tuntap_name, IFF_TUN | IFF_NO_PI)
+        fcntl.ioctl(tun, TUNSETIFF, ifr)
+        fcntl.ioctl(tun, TUNSETOWNER, 1000)
+
+        self._tuntap = tun
+
+    def _handle_rx_pdu(self, pdu):
+        print(msg)
+        os.write(self._tuntap.fileno(), pdu)
+
+    def _txthread_func(self):
+        log.info("tx thread started.")
+        while not self.shutdown:
+            rlist = [self._tuntap]
+
+            rready, wready, eready = select(rlist, [], [], 0.1)
+            log.info("select returned: {}, {}, {}".format(rready, wready, eready))
+
+            if rready:
+                data = os.read(self._tuntap.fileno(), 65536)
+                log.info("packet from TAP: {}".format(data))
+
+                # convert data to numpy
+                npdata = np.zeros(len(data), dtype=np.uint8)
+                for i in range(len(data)):
+                    npdata[i] = ord(data[i])
+
+                pmt_data = pmt.to_pmt(npdata)
+                pmt_pdu = pmt.cons(pmt.PMT_NIL, pmt_data)
+
+                self.message_port_pub(pmt.intern("packet_tx"), pmt_pdu)
+
+    def __init__(self, tuntap_name='hamnet70'):
+        gr.basic_block.__init__(self, name="Hamnet70 Controller", in_sig=None, out_sig=None)
+
+        self._tuntap_name = tuntap_name
+        self._txthread = None
+
+        self._tuntap_setup()
+
+        self.message_port_register_out(pmt.intern("packet_tx"))
+        self.message_port_register_in(pmt.intern("packet_rx"))
+
+        self.set_msg_handler(pmt.intern("packet_rx"), self._handle_rx_pdu)
+
+        self.start_txthread()
+
+    def __del__(self):
+        self.stop_txthread()
+        tun.close()
+
+    def start_txthread(self):
+        if not self._txthread:
+            self.shutdown = False
+
+            self._txthread = threading.Thread(target=self._txthread_func)
+            self._txthread.daemon = False
+            self._txthread.start()
+
+    def stop_txthread(self):
+        if self._txthread:
+            self.shutdown = True
+            self._txthread.join()
+            self._txthread = None
+
+
+class Hamnet70TopBlock(gr.top_block):
+    def __init__(self):
+        gr.top_block.__init__(self, "Top Block")
+
+        # Create blocks
+
+        self._controller = Hamnet70Controller()
+
+        self._mod = hamnet70_mod(samp_rate_0=200e3)
+        self._demod = hamnet70_demod(samp_rate=200e3)
+
+        self._input_fifo = blocks.file_source(gr.sizeof_gr_complex*1, 'rx.fifo', True)
+        self._output_fifo = blocks.file_sink(gr.sizeof_gr_complex*1, 'tx.fifo', False)
+
+        self._throttle = blocks.throttle(gr.sizeof_gr_complex*1, 200e3)
+
+        # Connect blocks
+        self.connect((self._input_fifo, 0), (self._throttle, 0))
+        self.connect((self._throttle, 0), (self._demod, 0))
+        self.msg_connect((self._demod, 'message_out'), (self._controller, 'packet_rx'))
+
+        self.msg_connect((self._controller, 'packet_tx'), (self._mod, 'packet_in'))
+        self.connect((self._mod, 0), (self._output_fifo, 0))
+
+if __name__ == "__main__":
+    top_block = Hamnet70TopBlock()
+    top_block.start()
+
+    try:
+        top_block.wait()
+    except KeyboardInterrupt:
+        top_block.stop()
diff --git a/controller/setup_tundev.sh b/controller/setup_tundev.sh
new file mode 100755
index 0000000..621da0e
--- /dev/null
+++ b/controller/setup_tundev.sh
@@ -0,0 +1,13 @@
+#!/bin/sh
+
+DEV=hamnet70
+
+if [ -z "$1" ]; then
+	NET=192.168.0.1/24
+else
+	NET="$1"
+fi
+
+sudo ip tuntap add dev $DEV user $(id -u) mode tun
+sudo ip addr add $NET dev $DEV
+sudo ip link set dev $DEV up