#!/usr/bin/env pythonfrom gnuradio import gr, gru, eng_notationfrom gnuradio import usrpfrom gnuradio.eng_option import eng_optionfrom gnuradio import eng_notationfrom gnuradio import optfirfrom optparse import OptionParserfrom gnuradio.wxgui import stdgui, fftsink, waterfallsink, scopesink, form, sliderimport wxfrom usrpm import usrp_dbidimport timeimport os.pathimport sys# required FPGA that can do 4 rx channels.class my_graph(gr.flow_graph):    def __init__(self):        gr.flow_graph.__init__(self)        parser = OptionParser (option_class=eng_option)        #parser.add_option("-S", "--subdev", type="subdev", default=(0, None),        #                  help="select USRP Rx side A or B (default=A)")        parser.add_option("-d", "--decim", type="int", default=128,                          help="set fgpa decimation rate to DECIM [default=%default]")        parser.add_option("-f", "--freq", type="eng_float", default=146.585e6,                          help="set frequency to FREQ [default=%default])", metavar="FREQ")        parser.add_option("-g", "--gain", type="eng_float", default=20,                          help="set gain in dB [default=%default]")        parser.add_option("-F", "--filter", action="store_true", default=True,                          help="Enable channel filter")        parser.add_option("-o", "--output", type="string", default=None,                          help="set output basename")        (options, args) = parser.parse_args()        if len(args) != 0:            parser.print_help()            raise SystemExit        if options.output is None:            parser.print_help()            sys.stderr.write("You must provide an output filename base with -o OUTPUT\n")            raise SystemExit        else:            basename = options.output        nchan = 4        nsecs = 4.0        if options.filter:            sw_decim = 4        else:            sw_decim = 1        self.u = usrp.source_c(0, options.decim, fpga_filename="std_4rx_0tx.rbf")        if self.u.nddc() < nchan:            sys.stderr.write('This code requires an FPGA build with %d DDCs.  This FPGA has only %d.\n' % (                nchan, self.u.nddc()))            raise SystemExit                                     if not self.u.set_nchannels(nchan):            sys.stderr.write('set_nchannels(%d) failed\n' % (nchan,))            raise SystemExit                input_rate = self.u.adc_freq() / self.u.decim_rate()        print "USB data rate   = %s" % (eng_notation.num_to_str(input_rate),)        sink_data_rate = input_rate/sw_decim        print "Scope data rate = %s" % (eng_notation.num_to_str(sink_data_rate),)        self.subdev = self.u.db[0] + self.u.db[1]        if (len(self.subdev) != 4 or            self.u.db[0][0].dbid() != usrp_dbid.BASIC_RX or            self.u.db[1][0].dbid() != usrp_dbid.BASIC_RX):            sys.stderr.write('This code requires a Basic Rx board on Sides A & B\n')            sys.exit(1)        self.u.set_mux(gru.hexint(0xf3f2f1f0))        # collect 1 second worth of data        limit = int(nsecs * input_rate * nchan)        print "limit = ", limit        head = gr.head(gr.sizeof_gr_complex, limit)        # deinterleave four channels from FPGA        di = gr.deinterleave(gr.sizeof_gr_complex)        self.connect(self.u, head, di)                # taps for channel filter        chan_filt_coeffs = optfir.low_pass (1,           # gain                                            input_rate,  # sampling rate                                            80e3,        # passband cutoff                                            115e3,       # stopband cutoff                                            0.1,         # passband ripple                                            60)          # stopband attenuation        #print len(chan_filt_coeffs)        for i in range(nchan):            sink = gr.file_sink(gr.sizeof_gr_complex,                                basename + ("-%s-%d.dat" % (eng_notation.num_to_str(sink_data_rate), i)))            if options.filter:                chan_filt = gr.fir_filter_ccf(sw_decim, chan_filt_coeffs)                self.connect((di, i), chan_filt, sink)            else:                self.connect((di, i), sink)        self.set_gain(options.gain)        self.set_freq(options.freq)    def set_gain(self, gain):        for i in range(len(self.subdev)):            self.subdev[i].set_gain(gain)    def set_freq(self, target_freq):        ok = True        for i in range(len(self.subdev)):            r = usrp.tune(self.u, i, self.subdev[i], target_freq)            if not r:                ok = False                print "set_freq: failed to set subdev[%d] freq to %f" % (                    i, target_freq)        return okdef main ():    my_graph().run()if __name__ == '__main__':    main ()