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

[Matt Ettus]

On 04/07/2010 09:10 PM, Jeff Brower wrote:
> 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.


Eventually I got completely fed up with the opencores gige core and 
wrote a completely new one from scratch (the simple_gemac).  It only 
does gigabit, though.

One of the main problems with 10/100/1000 in a spartan is that you need 
a large number of clocks and the S3 is constrained.  If you just want 
10/100 and can live without gigabit, I would suggest doing that, as it 
will save 1 or 2 clocks.

Matt