Re: High sample rate freeze (Manjaro/Arch problem?)

[Ryan Volz]

Hi,

This looks like a bug in UHD 4.0.0.0 that has been fixed but not yet released:

https://github.com/EttusResearch/uhd/issues/380

I think that leaves you a few options for workarounds that don't involve 
switching your distribution:

1) Compile UHD from source with a patch from the commit linked in that bug.
2) Ditch the Manjaro package and use an alternative package (e.g. conda, which 
still uses UHD 3.15: https://wiki.gnuradio.org/index.php/CondaInstall)
3) Get in contact with the Manjaro / Arch UHD maintainer and get them to update 
UHD with the patch.

Cheers,
Ryan

On 4/2/21 3:18 AM, Thomas Lavarenne wrote:
> Hello,
>
> I have a problem with my usrp b200 at high sample rates (> 6M) connected to USB (2 or 3). 
> Whatever the frequency, the signals on the QT frequency sink "do not move". the 
> computer is not frozen, I can still interact with the window, but the signal just freeze. 
> Everything works fine at a sample rate of 4M or below. I don't think this is a problem with 
> the usrp as it does the same with the hackrf.
> My GNU Radio version is 3.8.2.0 (python 3.9.2) and I have just switched from 
> ubuntu 20.04 to Manjaro (Arch based) and as everything worked well with ubuntu 
> with the same configuration and the same computer (usrp with sampling 
> frequency> 40M without problem) I suspect a problem with the Manjaro OS? Does 
> anyone here use Manjaro / Arch and has encountered a similar problem? I'm very 
> happy with the system by the way and I don't really want to switch back so quickly 
> ... :)
> The logs don't give much information when the problem occurs:
>
> [INFO] [UHD] linux; GNU C++ version 10.2.0; Boost_107500; UHD_4.0.0.0-0-unknown
> [INFO] [B200] Detected Device: B200
> [INFO] [B200] Operating over USB 3.
> [INFO] [B200] Initialize CODEC control...
> [INFO] [B200] Initialize Radio control...
> [INFO] [B200] Performing register loopback test...
> [INFO] [B200] Register loopback test passed
> [INFO] [B200] Setting master clock rate selection to 'automatic'.
> [INFO] [B200] Asking for clock rate 16.000000 MHz...
> [INFO] [B200] Actually got clock rate 16.000000 MHz.
> [INFO] [B200] Asking for clock rate 20.000000 MHz...
> [INFO] [B200] Actually got clock rate 20.000000 MHz.
> [INFO] [MULTI_USRP]     1) catch time transition at pps edge
> [INFO] [MULTI_USRP]     2) set times next pps (synchronously)
> O
>  >>> Done
>
> Thank you for the attention given to my problem,
>
> Thomas