#!/usr/bin/env python # # Copyright 2005-2007,2011 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 3, 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., 51 Franklin Street, # Boston, MA 02110-1301, USA. # from gnuradio import gr, optfir, audio, blks2, uhd from gnuradio import eng_notation from gnuradio.eng_option import eng_option from optparse import OptionParser import sys class wfm_rx_block (gr.top_block): def __init__(self): gr.top_block.__init__(self) parser=OptionParser(option_class=eng_option) parser.add_option("-a", "--args", type="string", default="", help="UHD device address args [default=%default]") parser.add_option("", "--spec", type="string", default=None, help="Subdevice of UHD device where appropriate") parser.add_option("-A", "--antenna", type="string", default=None, help="select Rx Antenna where appropriate") parser.add_option("-f", "--freq", type="eng_float", default=100.1e6, help="set frequency to FREQ", metavar="FREQ") parser.add_option("-g", "--gain", type="eng_float", default=None, help="set gain in dB (default is midpoint)") parser.add_option("-V", "--volume", type="eng_float", default=None, help="set volume (default is midpoint)") parser.add_option("-O", "--audio-output", type="string", default="default", help="pcm device name. E.g., hw:0,0 or surround51 or /dev/dsp") parser.add_option("", "--freq-min", type="eng_float", default=87.9e6, help="Set a minimum frequency [default=%default]") parser.add_option("", "--freq-max", type="eng_float", default=108.1e6, help="Set a maximum frequency [default=%default]") (options, args) = parser.parse_args() if len(args) != 0: parser.print_help() sys.exit(1) self.state = "FREQ" self.freq = 0 self.fm_freq_min = options.freq_min self.fm_freq_max = options.freq_max # build graph self.u = uhd.usrp_source(device_addr=options.args, stream_args=uhd.stream_args('fc32')) # Set the subdevice spec if(options.spec): self.u.set_subdev_spec(options.spec, 0) # Set the antenna if(options.antenna): self.u.set_antenna(options.antenna, 0) usrp_rate = 320e3 demod_rate = 320e3 audio_rate = 32e3 audio_decim = int(demod_rate / audio_rate) self.u.set_samp_rate(usrp_rate) dev_rate = self.u.get_samp_rate() nfilts = 32 chan_coeffs = optfir.low_pass (nfilts, # gain nfilts*usrp_rate, # sampling rate 80e3, # passband cutoff 115e3, # stopband cutoff 0.1, # passband ripple 60) # stopband attenuation rrate = usrp_rate / dev_rate self.chan_filt = blks2.pfb_arb_resampler_ccf(rrate, chan_coeffs, nfilts) self.guts = blks2.wfm_rcv (demod_rate, audio_decim) self.volume_control = gr.multiply_const_ff(1) # sound card as final sink self.audio_sink = audio.sink(int(audio_rate), options.audio_output, False) # ok_to_block # now wire it all together self.connect (self.u, self.chan_filt, self.guts, self.volume_control, self.audio_sink) if options.gain is None: # if no gain was specified, use the mid-point in dB g = self.u.get_gain_range() options.gain = float(g.start()+g.stop())/2.0 if options.volume is None: g = self.volume_range() options.volume = float(g[0]+g[1])/2 frange = self.u.get_freq_range() if(frange.start() > self.fm_freq_max or frange.stop() < self.fm_freq_min): sys.stderr.write("Radio does not support required frequency range.\n") sys.exit(1) if(options.freq < self.fm_freq_min or options.freq > self.fm_freq_max): sys.stderr.write("Requested frequency is outside of required frequency range.\n") sys.exit(1) # set initial values self.set_gain(options.gain) self.set_vol(options.volume) if not(self.set_freq(options.freq)): self._set_status_msg("Failed to set initial frequency") def set_vol (self, vol): g = self.volume_range() self.vol = max(g[0], min(g[1], vol)) self.volume_control.set_k(10**(self.vol/10)) self.update_status_bar () def set_freq(self, target_freq): """ Set the center frequency we're interested in. @param target_freq: frequency in Hz @rypte: bool """ r = self.u.set_center_freq(target_freq) if r: self.freq = target_freq self.update_status_bar() self._set_status_msg("OK", 0) return True self._set_status_msg("Failed", 0) return False def set_gain(self, gain): self.u.set_gain(gain) def update_status_bar (self): msg = "Freq: %s Volume:%f Setting:%s" % ( eng_notation.num_to_str(self.freq), self.vol, self.state) self._set_status_msg(msg, 1) def _set_status_msg(self, msg, which=0): print msg def volume_range(self): return (-20.0, 0.0, 0.5) if __name__ == '__main__': tb = wfm_rx_block() try: tb.run() except KeyboardInterrupt: pass