Re: packet_loopback_hier OTA problem

[Marcus Müller]

Hi Jack,

the background shows that there's regular underflows. This might be a bug, or 
your
computer being overtasked. Could you run e.g. `htop` or `top` to check how 
loaded your
CPUs are?

Best regards,

Marcus

DISCLAIMER: Any attached Code is provided As Is. It has not been tested or 
validated as a product, for use in a deployed application or system, or for use 
in hazardous environments. You assume all risks for use of the Code. Use of the 
Code is subject to terms of the licenses to the UHD or RFNoC code with which 
the Code is used. Standard licenses to UHD and RFNoC can be found at 
https://www.ettus.com/sdr-software/licenses/.

NI will only perform services based on its understanding and condition that the 
goods or services (i) are not for the use in the production or development of 
any item produced, purchased, or ordered by any entity with a footnote 1 
designation in the license requirement column of Supplement No. 4 to Part 744, 
U.S. Export Administration Regulations and (ii) such a company is not a party 
to the transaction.  If our understanding is incorrect, please notify us 
immediately because a specific authorization may be required from the U.S. 
Commerce Department before the transaction may proceed further.

On 07.07.21 19:22, jack houston wrote:
> When running the packet loopback example, from version 3.10, it works as 
> expected
> without SDR involvement. However when using an SDR sink and source I have no 
> luck with
> it working. I have tried using different configurations of sdrs, frequencies 
> and gain
> values all known to be working on other topologies. As an example, I can use 
> my Ettus
> B205 on a OFDM packet topology using BPSK and can correctly send and receive 
> packets bar
> some padding issues. Using the same UHD with similiar bit rate and gain 
> values on the
> packet_loopback_hier example yields nothing.
> The only error I that I've received is a ursp sink underflow error which 
> should be
> irrelevant. Included is a link of a screenshot of the example file running. I 
> was told
> by a colleague that the example has been broken for a while, but if it works 
> under
> simulation I don't believe thats the case. From what I can tell something is 
> not
> correctly working on the RX side of the topology, either at the PCS or the 
> HPD. If
> someone has any knowledge about the example file and what could be causing it 
> to not
> work in my case, I would be delighted to hear about it.
>
> File running: https://imgur.com/a/orVuSZ5 <https://imgur.com/a/orVuSZ5>