Re: [Discuss-gnuradio] FPGA Modifications for a Continuous Carrier?

[Michael P Buettner]

On Tue, 24 Jul 2007, Brian Padalino wrote:
> You can see how at line 72 there is a case statement and if the TX
> FIFO is empty, the values are set to be zero.  I am not 100% sure, but
> I believe if you change these values to be non-zero you will get a
> carrier to come out.
>
> Moreover, once the TX FIFOs are filled with something, that data will
> then automatically switch over for you.
>
> The only thing I'd be worried about is the master control register
> which controls whether or not the TX strobes are enabled.  You can see
> this here:
>   
> http://gnuradio.org/trac/browser/gnuradio/trunk/usrp/fpga/sdr_lib/master_control.v
>
> Follow the 'enable_tx' signal around to see what I mean.
>
> You may want to dig into Verilog simulation a bit if you have the
> time.  There are testbenches that are written and in the repository
> that allow you to see what the changes you make will have on the code.
>
> I hope this helps.
>
> Brian

 Thanks Brian, that was just what I was looking for.  I've now enough to dig 
into anyway, and we'll see what happens.

  Are there any current testbenches?  The only testbench I can find is 
full_chip which is defunct.

  Thanks again.

 michael