[USRP-users] b200 Overflows

Marcus D. Leech mleech at ripnet.com
Sat Sep 27 14:11:15 EDT 2014


On 09/27/2014 02:00 PM, Simon Brown via USRP-users wrote:
>
> Thanks,
>
> I've tried changing these, still get overruns with sample rates of 
> 8MS/s or higher.
>
> Simon Brown G4ELI
> http://v2.sdr-radio.com
>
Are you sure that your USB-3.0 interface is actually dealing with the 
device as a USB-3.0 and not a USB-2.0 device?

If you specify a wire-format of sc8 or sc12, do the overruns go away?  
This will help distinguish between cases involving CPU exhaustion, and 
interior
   bus deficiencies  (I found this on one of my embedded systems--could 
sustain only 6.4Msps with full-width samples, but was perfectly happy to
   stream 12.8Msps with 8-bit samples).


> *From:*USRP-users [mailto:usrp-users-bounces at lists.ettus.com] *On 
> Behalf Of *Marcus D. Leech via USRP-users
> *Sent:* 26 September 2014 20:03
> *To:* usrp-users at lists.ettus.com
> *Subject:* Re: [USRP-users] b200 Overflows
>
> On 09/26/2014 02:18 PM, Simon Brown via USRP-users wrote:
>
>     Hi,
>
>     Windows 64-bit: I'm streaming nicely, none of my threads indicate
>     CPU problems (plenty of headroom). At 8MB/s and higher I'm getting
>     fastpath Overrun messages every second or so even though I'm
>     pulling data from the b200 as fast as it's available, I am not CPU
>     limited in any way. Using Intel USB 3.
>
>     FWIW I don't see any way to tune the uhd::rx_streamer -- bigger /
>     more buffers, also I don't see any way to flush either.
>
>     Interestingly if I get my CUDA card working harder (more work on
>     the bus) the Overrun messages appear more frequently. I7 4770k,
>     good motherboard (can't remember what).
>
>     Any suggestions?
>
>     Simon Brown G4ELI
>     http://v2.sdr-radio.com
>
>
>
>
>     _______________________________________________
>
>     USRP-users mailing list
>
>     USRP-users at lists.ettus.com  <mailto:USRP-users at lists.ettus.com>
>
>     http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
> The USB transport parameters can be tweaked:
>
> http://files.ettus.com/manual/page_transport.html#transport_usb_params
>
>
> _______________________________________________
> USRP-users mailing list
> USRP-users at lists.ettus.com
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com


-- 
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/attachments/20140927/abd09bba/attachment-0002.html>


More information about the USRP-users mailing list