[Discuss-gnuradio] Unable to find USRP #0

[Lee Patton]

I just started using my RFX-2400 today, and all was going well.  I had
used usrp_{oscope,fft}.py as regular user without incident.  All of a
sudden, I started getting the "Unable to find USRP #0" runtime error. 

It is probably something I've done, but I have no idea what.  The usbfs
is mounted. I ran the scripts as both regular user as well as root. The
LED is flashing at about 10 Hz.  

Potentially helpful background:
Sometime ago, I upgraded to my kernel (so I could use my IPod) from
2.6.9 to 2.6.12  using the package manager under Fedora Core 3.  Things
seemed a little screwy after that. So, I always boot into 2.6.9 now.
Recently, I noticed I can no longer use my USB pen drive or external
hard drive. Something keeps deleting /dev/sda*.  However, I mount the
USRP under /proc/bus/usb, which is still there.

Any ideas?  Here's the error message.

Traceback (most recent call last):
  File "./usrp_fft.py", line 237, in ?
    main ()
  File "./usrp_fft.py", line 233, in main
    app = stdgui.stdapp(app_flow_graph, "USRP FFT", nstatus=1)
  File "/gnuradio/gr/lib/python2.3/site-
packages/gnuradio/wxgui/stdgui.py", line  36, in __init__
    wx.App.__init__ (self, redirect=False)
  File "/gnuradio/gr/lib/python2.3/site-packages/wx-2.6-gtk2-
ansi/wx/_core.py", line 7473, in __init__
    self._BootstrapApp()
  File "/gnuradio/gr/lib/python2.3/site-packages/wx-2.6-gtk2-
ansi/wx/_core.py", line 7125, in _BootstrapApp
    return _core_.PyApp__BootstrapApp(*args, **kwargs)
  File "/gnuradio/gr/lib/python2.3/site-
packages/gnuradio/wxgui/stdgui.py", line  39, in OnInit
    frame = stdframe (self.flow_graph_maker, self.title, self._nstatus)
  File "/gnuradio/gr/lib/python2.3/site-
packages/gnuradio/wxgui/stdgui.py", line  60, in __init__
    self.panel = stdpanel (self, self, flow_graph_maker)
  File "/gnuradio/gr/lib/python2.3/site-
packages/gnuradio/wxgui/stdgui.py", line  81, in __init__
    self.fg = flow_graph_maker (frame, self, vbox, sys.argv)
  File "./usrp_fft.py", line 78, in __init__
    self.u = usrp.source_c(decim_rate=options.decim)
  File "/gnuradio/gr/lib/python2.3/site-packages/gnuradio/usrp.py", line
240, in  __init__
    _ensure_rev2(which)
  File "/gnuradio/gr/lib/python2.3/site-packages/gnuradio/usrp.py", line
82, in _ensure_rev2
    v = _look_for_usrp(which)
  File "/gnuradio/gr/lib/python2.3/site-packages/gnuradio/usrp.py", line
76, in _look_for_usrp
    raise RuntimeError, "Unable to find USRP #%d" % (which,)
RuntimeError: Unable to find USRP #0