[Discuss-gnuradio] My old gnu radio code ( 2007) does not work now :(

[Bisu Bahadur]

Hi All,

  I am running gnu radio-3.2.2 now. I haven't used gnuradio in a while (since 2007). I had a old gnuradio code (from a project) that generated a signal repeatedly until I ask it to stop, and the source came from a vector source defined in the program (please see below). I know "flow_graph" has been changed to "top_block". I made that change, rest of the old code didn't complain while compiling. However, it does not produce the signal I would like it to produce (checked it on the spectrum analyzer). Could you please tell me what else, I need to change. It used to run perfectly in the old version of gnuradio (around May 2007). Thank you for your time.

===========================The code with flow_graph changed into top_block==============================

from datetime import datetime
from gnuradio import gr,usrp
from gnuradio import eng_notation
from optparse import OptionParser
from gnuradio.eng_option import eng_option

class my_top_block(gr.top_block):
    def __init__(self, my_carrier, period, pulse, seq, interp=64):
        global dest, src, sample_rate
        global carrier
        global BARK, QAM
        global vector
        self.BARK = 2
        self.QAM = 1
       
        carrier = my_carrier
        self.vector = []
       
        gr.top_block.__init__(self)
        nchan = 1
        duc0 = 5e6
        self.dest = usrp.sink_c (0, interp, nchan)


        self.sample_rate = self.dest.dac_freq() / interp
        self.src = "">        self.dest.set_tx_freq(0, duc0) 
        self.dest.set_pga(0,0)
       
        max = 2**15 - 1
        min = -max
        if seq == self.QAM:
            n = 4
        else:
            n = 11
       
        nWidth = int(pulse*(self.sample_rate/1e6))
        nPulse = int(nWidth/n)
        nPeriod = int(period*(self.sample_rate/1e6))
        nIdle = nPeriod - nPulse
       
        if seq == self.QAM:
            for i in range(nPulse):
                self.vector.append(complex(max,max))
                self.vector.append(complex(max,min))
                self.vector.append(complex(min,max))
                self.vector.append(complex(min,min))
        else:
            for i in range(nPulse):
                self.vector.append(complex(max,0))
                self.vector.append(complex(min,0))
                self.vector.append(complex(max,0))
                self.vector.append(complex(max,0))
                self.vector.append(complex(min,0))
                self.vector.append(complex(max,0))
                self.vector.append(complex(max,0))
                self.vector.append(complex(max,0))
                self.vector.append(complex(min,0))
                self.vector.append(complex(min,0))
                self.vector.append(complex(min,0))
               
        for i in range(nIdle):
            self.vector.append(complex(0,0))
        self.buildGraph()
           
    def buildGraph(self):
        self.disconnect_all()
       
        self.src = "" True)
       
        self.connect(self.src, self.dest)

        # Get an instance of daughterboard
        dboard = usrp.selected_subdev(self.dest, (0,0))
        dboard.set_gain(90)
      
        # Display the name of the daughterboard
        print "Signal will be generate by :", dboard.side_and_name()
     
       # The parameters are which motherboard, daughterboard, the carrier frequence
        rf = self.dest.tune(dboard.which(), dboard, carrier) 
     
        if rf:
          print "Carrier :",carrier
        else:
          print "The range of the daugtherboard's frequency is :", \
          eng_notation.num_to_str(dboard.freq_range()[0]), "-", \
          eng_notation.num_to_str(dboard.freq_range()[1])
          raise SystemExit
        self.start()
       
if __name__ == "__main__":
    parser = OptionParser (option_class=eng_option)
    parser.add_option ("-p", "--pulse-width", type="int", default=35,
                       help="pulse width of jamming signal in microseconds")
    parser.add_option ("-j", "--period", type="int", default=400,
                       help="idle width of jamming signal in microseconds")
    parser.add_option ("-c", "--carrier", type="float", default=2.462e9,
                       help="the carrier frequency")
    parser.add_option ("--qam", dest="seq", action="" const=1,
                       help="generate QAM signals", default = 1)
    parser.add_option ("--barker", dest="seq", action="" const=2,
                       help="generate a BARKER sequence")
    (options, args) = parser.parse_args ()
   
    if len(args) != 0:
        parser.print_help()
        raise SystemExit
   
    g = my_top_block(options.carrier, options.period, options.pulse_width, options.seq)
    print options
    raw_input("Hit enter to stop: ")
    g.stop()