From 5d69a524f81f234b3fbc41d49ba18d6f6886baba Mon Sep 17 00:00:00 2001 From: jcorgan Date: Thu, 3 Aug 2006 04:51:51 +0000 Subject: Houston, we have a trunk. git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@3122 221aa14e-8319-0410-a670-987f0aec2ac5 --- gnuradio-examples/python/gmsk2/tunnel.py | 300 +++++++++++++++++++++++++++++++ 1 file changed, 300 insertions(+) create mode 100755 gnuradio-examples/python/gmsk2/tunnel.py (limited to 'gnuradio-examples/python/gmsk2/tunnel.py') diff --git a/gnuradio-examples/python/gmsk2/tunnel.py b/gnuradio-examples/python/gmsk2/tunnel.py new file mode 100755 index 000000000..bc10d3e34 --- /dev/null +++ b/gnuradio-examples/python/gmsk2/tunnel.py @@ -0,0 +1,300 @@ +#!/usr/bin/env python +# +# Copyright 2005,2006 Free Software Foundation, Inc. +# +# This file is part of GNU Radio +# +# GNU Radio is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2, or (at your option) +# any later version. +# +# GNU Radio is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with GNU Radio; see the file COPYING. If not, write to +# the Free Software Foundation, Inc., 59 Temple Place - Suite 330, +# Boston, MA 02111-1307, USA. +# + + +# ///////////////////////////////////////////////////////////////////////////// +# +# This code sets up up a virtual ethernet interface (typically gr0), +# and relays packets between the interface and the GNU Radio PHY+MAC +# +# What this means in plain language, is that if you've got a couple +# of USRPs on different machines, and if you run this code on those +# machines, you can talk between them using normal TCP/IP networking. +# +# ///////////////////////////////////////////////////////////////////////////// + + +from gnuradio import gr, gru, blks +from gnuradio import usrp +from gnuradio import eng_notation +from gnuradio.eng_option import eng_option +from optparse import OptionParser + +import random +import time +import struct +import sys +import os + +# from current dir +from transmit_path import transmit_path +from receive_path import receive_path +import fusb_options + +#print os.getpid() +#raw_input('Attach and press enter') + + +# ///////////////////////////////////////////////////////////////////////////// +# +# Use the Universal TUN/TAP device driver to move packets to/from kernel +# +# See /usr/src/linux/Documentation/networking/tuntap.txt +# +# ///////////////////////////////////////////////////////////////////////////// + +# Linux specific... +# TUNSETIFF ifr flags from + +IFF_TUN = 0x0001 # tunnel IP packets +IFF_TAP = 0x0002 # tunnel ethernet frames +IFF_NO_PI = 0x1000 # don't pass extra packet info +IFF_ONE_QUEUE = 0x2000 # beats me ;) + +def open_tun_interface(tun_device_filename): + from fcntl import ioctl + + mode = IFF_TAP | IFF_NO_PI + TUNSETIFF = 0x400454ca + + tun = os.open(tun_device_filename, os.O_RDWR) + ifs = ioctl(tun, TUNSETIFF, struct.pack("16sH", "gr%d", mode)) + ifname = ifs[:16].strip("\x00") + return (tun, ifname) + + +# ///////////////////////////////////////////////////////////////////////////// +# the flow graph +# ///////////////////////////////////////////////////////////////////////////// + +class my_graph(gr.flow_graph): + + def __init__(self, mod_class, demod_class, tx_subdev_spec, rx_subdev_spec, + bitrate, decim_rate, interp_rate, spb, + bt, rx_callback, options): + + gr.flow_graph.__init__(self) + self.txpath = transmit_path(self, mod_class, tx_subdev_spec, + bitrate, interp_rate, spb, + bt, options) + self.rxpath = receive_path(self, demod_class, rx_subdev_spec, + bitrate, decim_rate, spb, + rx_callback, options) + + def send_pkt(self, payload='', eof=False): + return self.txpath.send_pkt(payload, eof) + + def carrier_sensed(self): + """ + Return True if the receive path thinks there's carrier + """ + return self.rxpath.carrier_sensed() + + +# ///////////////////////////////////////////////////////////////////////////// +# Carrier Sense MAC +# ///////////////////////////////////////////////////////////////////////////// + +class cs_mac(object): + """ + Prototype carrier sense MAC + + Reads packets from the TUN/TAP interface, and sends them to the PHY. + Receives packets from the PHY via phy_rx_callback, and sends them + into the TUN/TAP interface. + + Of course, we're not restricted to getting packets via TUN/TAP, this + is just an example. + """ + def __init__(self, tun_fd, verbose=False): + self.tun_fd = tun_fd # file descriptor for TUN/TAP interface + self.verbose = verbose + self.fg = None # flow graph (access to PHY) + + def set_flow_graph(self, fg): + self.fg = fg + + def phy_rx_callback(self, ok, payload): + """ + Invoked by thread associated with PHY to pass received packet up. + + @param ok: bool indicating whether payload CRC was OK + @param payload: contents of the packet (string) + """ + if self.verbose: + print "Rx: ok = %r len(payload) = %4d" % (ok, len(payload)) + if ok: + os.write(self.tun_fd, payload) + + def main_loop(self): + """ + Main loop for MAC. + Only returns if we get an error reading from TUN. + + FIXME: may want to check for EINTR and EAGAIN and reissue read + """ + min_delay = 0.001 # seconds + + while 1: + payload = os.read(self.tun_fd, 10*1024) + if not payload: + self.fg.send_pkt(eof=True) + break + + if self.verbose: + print "Tx: len(payload) = %4d" % (len(payload),) + + delay = min_delay + while self.fg.carrier_sensed(): + sys.stderr.write('B') + time.sleep(delay) + if delay < 0.050: + delay = delay * 2 # exponential back-off + + self.fg.send_pkt(payload) + + +# ///////////////////////////////////////////////////////////////////////////// +# main +# ///////////////////////////////////////////////////////////////////////////// + +def main(): + + parser = OptionParser (option_class=eng_option) + parser.add_option("-f", "--freq", type="eng_float", default=423.1e6, + help="set Tx and Rx frequency to FREQ [default=%default]", metavar="FREQ") + parser.add_option("-r", "--bitrate", type="eng_float", default=None, + help="specify bitrate. spb and interp will be derived.") + parser.add_option("-g", "--rx-gain", type="eng_float", default=27, + help="set rx gain") + parser.add_option("-T", "--tx-subdev-spec", type="subdev", default=None, + help="select USRP Tx side A or B") + parser.add_option("-R", "--rx-subdev-spec", type="subdev", default=None, + help="select USRP Rx side A or B") + parser.add_option("-S", "--spb", type="int", default=None, help="set samples/baud [default=%default]") + parser.add_option("-d", "--decim", type="intx", default=None, + help="set fpga decim rate to DECIM [default=%default]") + parser.add_option("-i", "--interp", type="intx", default=None, + help="set fpga interpolation rate to INTERP [default=%default]") + parser.add_option("-c", "--carrier-threshold", type="eng_float", default=30, + help="set carrier detect threshold (dB) [default=%default]") + parser.add_option("", "--bt", type="float", default=0.3, help="set bandwidth-time product [default=%default]") + parser.add_option("","--tun-device-filename", default="/dev/net/tun", + help="path to tun device file [default=%default]") + parser.add_option("-v","--verbose", action="store_true", default=False) + fusb_options.add_options(parser) + (options, args) = parser.parse_args () + + if len(args) != 0: + parser.print_help() + sys.exit(1) + + if options.freq < 1e6: + options.freq *= 1e6 + + # open the TUN/TAP interface + (tun_fd, tun_ifname) = open_tun_interface(options.tun_device_filename) + + # Attempt to enable realtime scheduling + r = gr.enable_realtime_scheduling() + if r == gr.RT_OK: + realtime = True + else: + realtime = False + print "Note: failed to enable realtime scheduling" + + + # If the user hasn't set the fusb_* parameters on the command line, + # pick some values that will reduce latency. + + if options.fusb_block_size == 0 and options.fusb_nblocks == 0: + if realtime: # be more aggressive + options.fusb_block_size = gr.prefs().get_long('fusb', 'rt_block_size', 1024) + options.fusb_nblocks = gr.prefs().get_long('fusb', 'rt_nblocks', 16) + else: + options.fusb_block_size = gr.prefs().get_long('fusb', 'block_size', 4096) + options.fusb_nblocks = gr.prefs().get_long('fusb', 'nblocks', 16) + + print "fusb_block_size =", options.fusb_block_size + print "fusb_nblocks =", options.fusb_nblocks + + # instantiate the MAC + mac = cs_mac(tun_fd, verbose=True) + + + # build the graph (PHY) + fg = my_graph(blks.gmsk2_mod, blks.gmsk2_demod, + options.tx_subdev_spec, options.rx_subdev_spec, + options.bitrate, options.decim, options.interp, + options.spb, options.bt, mac.phy_rx_callback, + options) + + mac.set_flow_graph(fg) # give the MAC a handle for the PHY + + if fg.txpath.bitrate() != fg.rxpath.bitrate(): + print "WARNING: Transmit bitrate = %sb/sec, Receive bitrate = %sb/sec" % ( + eng_notation.num_to_str(fg.txpath.bitrate()), + eng_notation.num_to_str(fg.rxpath.bitrate())) + + print "bitrate: %sb/sec" % (eng_notation.num_to_str(fg.txpath.bitrate()),) + print "spb: %3d" % (fg.txpath.spb(),) + print "interp: %3d" % (fg.txpath.interp(),) + + ok = fg.txpath.set_freq(options.freq) + if not ok: + print "Failed to set Tx frequency to %s" % (eng_notation.num_to_str(options.freq),) + raise SystemExit + + ok = fg.rxpath.set_freq(options.freq) + if not ok: + print "Failed to set Rx frequency to %s" % (eng_notation.num_to_str(options.freq),) + raise SystemExit + + fg.rxpath.set_gain(options.rx_gain) + print "Rx gain_range: ", fg.rxpath.subdev.gain_range(), " using", fg.rxpath.gain + + fg.rxpath.set_carrier_threshold(options.carrier_threshold) + print "Carrier sense threshold:", options.carrier_threshold, "dB" + + print + print "Allocated virtual ethernet interface: %s" % (tun_ifname,) + print "You must now use ifconfig to set its IP address. E.g.," + print + print " $ sudo ifconfig %s 10.10.10.1" % (tun_ifname,) + print + print "Be sure to use a different address in the same subnet for each machine." + print + + + fg.start() # Start executing the flow graph (runs in separate threads) + + mac.main_loop() # don't expect this to return... + + fg.stop() # but if it does, tell flow graph to stop. + fg.wait() # wait for it to finish + + +if __name__ == '__main__': + try: + main() + except KeyboardInterrupt: + pass -- cgit