Re: [Discuss-gnuradio] MAC layer development and USRP2

[Jeff Brower]

George-

>> Did you see my previous post about the accelerator PCIe card?  To some
>> extent the Microsoft approach is what we're
>> doing.  But we want to stay compatible with USRP2 hardware so we connect
>> GbE to the accelerator card; non MAC-related
>> dataflow is PCIe from there.  Buffering required to stay compatible with
>> USRP2 software and high, sustained transfer
>> rates moves "right", to the accelerator card (which has a lot of memory).
>>
>>
> Interesting, I didn't see this post.  I tried doing some googling for it but
> I couldn't turn up with it.  What was the subject of the post?

Here is the archive copy:

  http://lists.gnu.org/archive/html/discuss-gnuradio/2010-03/msg00481.html

>> The real trick is software.  Our approach is that MAC-related code still
>> appears in GNU radio source, but is marked
>> with pragmas (first something specific to our project, then OpenCL, then
>> OpenMP) so that code actually runs on the
>> accelerator card (the TI multicore CPUs on the acclerator card run
>> arbitrary C/C++ code so they're not limited like an
>> Nvidia or other GPU).  We plan to use our GNU radio interface to test
>> results of a server acceleration project we're
>> doing for DoE.
>
>> That's the long story... right now our short-term objective is the
>> GbE-to-GbE USRP2 connection.
>
> So right now you're trying to get low latency, but high throughput, between
> two USRP2's connected directly via GbE?  So you're not using the frontend?

No, one USRP2 connected to the accelerator card (which is PCI or PCIe).  We 
want to stay as compatible as possible
with all USRP2 hardware.

-Jeff