Re: **Cant use UHD SINK and UHD Source in the same flowgraph

[Marcus D. Leech]

On 16/01/2023 16:30, Taylor Clark wrote:
> sorry about that,
>
> I am away from the laptop but I am using
> maint3. 8-gnauradio(v3.8.5.0 to be specific)
> uhd v4. 3.0-rc2
>
> I will also note I have tried gnuradio v3.9.4.0 and have the same 
> problem. the device is claimed by one uhd block which functions.  I 
> didn't know if gnuradio was in charge of executing the networking via 
> uhd or not but I believe the uhd blocks are not started at the same 
> time and uhd cannot claim a device that is already claimed
>
> in the flowgraph I am targeting the same x410 with type=x4xx in the 
> uhd sink and source block.
>
> I am using a zmq server for getting data, adding crc and fec with 
> modulation then outputting to uhd sink. Over an ssma cable on the 
> physical device I plug tx/Rx into RX2.  I then use uhd source on the 
> same flow graph to read it.
>
> again, thank you for your consideration!
Are you specifying the SFP+ streaming-port address, or the management 
address?

Gnu Radio has no idea what UHD does "under the covers".    UHD knows how 
to deal with the situation where there's both a
  "source" and a "sink".  It has handled this configuration since the 
very beginning.

It would be useful to see your flow-graph (or, even better, a minimum 
flow-graph that displays the issue).

I don't have an X410 myself, but other network-based USRPs are used ALL 
THE TIME for flow-graphs that use it in both
  directions simultaneously...