Forum: GNU Radio Problem downloading firmware to USRP

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Natalia Olano (Guest)
on 2009-05-20 11:28
(Received via mailing list)
Hello all,

I am using a USRP Rev. 4.5 that has been working perfectly for a while
with gnuradio trunk rev. 10786. Suddenly I started getting the error:
usrp: failed to find usrp[0] when I try to run any gnuradio code. For
example, the output of

usrp: failed to find usrp[0]
Traceback (most recent call last):
  File "/usr/local/bin/", line 65, in <module>
    main ()
  File "/usr/local/bin/", line 58, in main
    tb = build_graph ()
  File "/usr/local/bin/", line 45, in build_graph
    usrp_tx = usrp.sink_s (0, tx_interp)
line 2776, in sink_s
    return _usrp_swig.sink_s(*args, **kwargs)
RuntimeError: can't open usrp

I have noticed that the LED of the USB controller is always blinking
at 3 Hz and never slows down. If I understand right from the FAQ, this
must mean the regular firmware is not properly downloaded. Could
anyone help me solve this?

Thanks in advance
Natalia Olano
Sebastiaan H. (Guest)
on 2009-05-21 07:52
(Received via mailing list)

Maybe you should have a look at /usr/local/share/usrp where the .rbf
files that get downloaded to the USRP are?  Try specifying a .rbf file
when you initialise the USRP in your script.

I'm just guessing a bit here.


Hello Sebastiaan,

Thanks a lot for your prompt answer. Yes I am using Ubuntu and I
execute the scripts as root.  However, I also configured once the
access for another user in the system called default. So the commands
you suggested look like:

$ cat /etc/group|grep usrp
$ cat /etc/udev/rules.d/10-usrp.rules
ACTION=="add", BUS=="usb", SYSFS{idVendor}=="fffe",
SYSFS{idProduct}=="0002", GROUP:="usrp", MODE:="0660"

The thing is that I can use the same gnuradio installation with a
different USRP and it works, so I would say this is a USRP problem
rather than a permissions problem.

There is also this issue with the LED only blinking at higher speed
and never slowing down that I mentioned in my email to the list. What
could be happening?

Best regards
Natalia Olano

2009/5/20 Sebastiaan H. <removed_email_address@domain.invalid>:
Natalia Olano (Guest)
on 2009-05-26 12:25
(Received via mailing list)
Hello again,

Thanks a lot for the help. I managed to get it to work again with the
help of the usrper function as in:

Best regards
Natalia Olano

2009/5/20 Sebastiaan H. <removed_email_address@domain.invalid>:
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