Re: [Discuss-gnuradio] USRP2 spontaneously dies while transmitting

[Andrew Lutomirski]

On Tue, Aug 4, 2009 at 5:52 PM, Eric Blossom<address@hidden> wrote:
> On Tue, Aug 04, 2009 at 04:38:56PM -0400, Andrew Lutomirski wrote:
>> Hi all-
>>
>> Occasionally, while transmitting, my USRP2 will die -- that is, it
>> stops reliably transmitting and then it drops off the network and
>> doesn't come back until restarted.  Any ideas?  I'm running some
>> vaguely recent firmware, but I've also seen this problem with the
>> version from the factory.
>>
>> (This is one of the beta units, which is supposed to be identical to
>> the modern version for these purposes.)
>>
>> Here's what triggered it most recently:
>>
>> $ tx_samples -i 20 -r -I /data/cal_signal
>> Failed to enable realtime scheduling
>> usrp2: failed to enable realtime scheduling
>> Daughterboard configuration:
>>   baseband_freq=0.000000
>>        duc_freq=0.000000
>>   residual_freq=0.000000
>>        inverted=no
>>
>> ^C
>> $ tx_samples -i 20 -r -I /data/cal_signal
>> Failed to enable realtime scheduling
>> terminate called after throwing an instance of 'std::runtime_error'
>>   what():  No USRPs found on interface eth0
>> Aborted
>>
>> $ tx_samples -i 20 -r -I /data/cal_signal
>> Failed to enable realtime scheduling
>> terminate called after throwing an instance of 'std::runtime_error'
>>   what():  No USRPs found on interface eth0
>> Aborted
>>
>> Thanks,
>> Andy
>
>
> First off, I highly suggest that you add yourself to group usrp if
> you're not already, then add this line to /etc/security/limits.conf:
>
> address@hidden  - rtprio 50

Already tried that and it didn't help.

I'm using an Intel 82566DC-2 (e1000e) attached to a switch, which is a
terrible idea, but I don't really mind occasional flakiness.

My main objection is that I have to reboot the USRP2 when it dies.
I'd expect it to recover.

Also, tx_samples often freaks out and saturates the network, even at
interpolation 20.  IMO that shouldn't happen no matter what happens to
priorities, the link, the network card, or the USRP.

>
>
> Do you have the TTL serial port on the USRP2 connected?  If so, what
> was the last thing it said?

Nope.  I might try that eventually, but I probably won't get a chance
for a week or two.

--Andy