Re: [Discuss-gnuradio] Re: interfacing a DSP array card to USRP2

[Jeff Brower]

Matt-

About Vikram's 10/100 mode question, we were wondering if it's a design flaw; 
i.e. something wrong from the start in
the original opencores.org source, or if it's fixable but hasn't been a high 
priority item given USRP2's high data
rate requirements.  But then I found this post:

  http://www.ruby-forum.com/topic/143084

So I guess the former.  If there are any hints you can give on what's wrong, we 
can take a look.  Maybe our guys can
get it working.

-Jeff

> Thank you for your email.
>
>> The mac is all contained in simple_gemac, and above that in
>> simple_gemac_wrapper:
>> http://code.ettus.com/redmine/ettus/projects/fpga/repository/revisions/master/show/usrp2/simple_gemac
>> simple_gemac_wrapper in the fifo_2clock_cascade files.
>> which is instantiated in u2_core.  Most of the buffering happens in
>> I would just start with the u2_core and simple_gemac_wrapper.  If you're
>> not using the SERDES, that is a good place to start ripping out.
>
> Does this imply that we can pull out the aeMB core, the 32K RAM and the
> buffer pool under module u2_core ?
>
> To carry out preliminary testing we need to be able to pass data to the
> gemac and configure appropriate control registers. Could you please
> suggest what existing modules we could reuse to send data to the gemac ?
>
>>> 3) Do you have an FPGA internal achitecture block diagram of any
>>> type?  Is there another group you're aware of doing such "major
>>> modification" FPGA work that we might talk to?
>>
>> There were some on the wiki at one time.  If they're not still there
>> I'll post a talk I did which covers the architecture.
>
> I have looked at the wiki (http://gnuradio.org/redmine/wiki/gnuradio),
> however i was not able to find any block diagrams for the internal
> architecture of the FPGA for USRP2. I still might not be look at the
> right place. Could you please point me in the right direction ?
>
>  From forum discussions over the past couple of months it appears that
> USRP2 does not support the 10/100 mode. Could you please help us
> understand the work effort involved in getting the 10/100 mode working ?
>
> Thanks and Regards,
> Vikram.
>