Forum: GNU Radio how to get out of this error

venkateswarlu@ubuntu:/usr/local/bin$ uhd_fft
linux; GNU C++ version 4.5.2; Boost_104200; 
UHD_003.004.003-247-g76f4e4d3

Traceback (most recent call last):
  File "/usr/local/bin/uhd_fft", line 337, in <module>
    main ()
  File "/usr/local/bin/uhd_fft", line 333, in main
    app = stdgui2.stdapp(app_top_block, "UHD FFT", nstatus=1)
  File 
"/usr/local/lib/python2.7/dist-packages/gnuradio/wxgui/stdgui2.py",
line 38, in __init__
    wx.App.__init__ (self, redirect=False)
  File 
"/usr/lib/python2.7/dist-packages/wx-2.8-gtk2-unicode/wx/_core.py",
line 7978, in __init__
    self._BootstrapApp()
  File 
"/usr/lib/python2.7/dist-packages/wx-2.8-gtk2-unicode/wx/_core.py",
line 7552, in _BootstrapApp
    return _core_.PyApp__BootstrapApp(*args, **kwargs)
  File 
"/usr/local/lib/python2.7/dist-packages/gnuradio/wxgui/stdgui2.py",
line 42, in OnInit
    self._max_noutput_items)
  File 
"/usr/local/lib/python2.7/dist-packages/gnuradio/wxgui/stdgui2.py",
line 64, in __init__
    self.panel = stdpanel (self, self, top_block_maker, max_nouts)
  File 
"/usr/local/lib/python2.7/dist-packages/gnuradio/wxgui/stdgui2.py",
line 86, in __init__
    self.top_block = top_block_maker (frame, self, vbox, sys.argv)
  File "/usr/local/bin/uhd_fft", line 91, in __init__
    otw_format=options.wire_format, args=options.stream_args))
  File 
"/usr/local/lib/python2.7/dist-packages/gnuradio/uhd/__init__.py",
line 116, in constructor_interceptor
    return old_constructor(*args)
  File 
"/usr/local/lib/python2.7/dist-packages/gnuradio/uhd/uhd_swig.py",
line 2827, in usrp_source
    return _uhd_swig.usrp_source(*args)
RuntimeError: LookupError: KeyError: No devices found for ----->

On 11/04/2012 04:05 AM, Vidyadhar Reddy Gosala wrote:
> line 38, in __init__
> "/usr/local/lib/python2.7/dist-packages/gnuradio/wxgui/stdgui2.py",
>   File "/usr/local/bin/uhd_fft", line 91, in __init__
>
>
> _______________________________________________
> Discuss-gnuradio mailing list
> Discuss-gnuradio@gnu.org
> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
On many systems, firewall rules prevent the auto-discovery mechanism
from working.

try

uhd_fft --args "addr=ip-addr-of-usrp"