Re: [Discuss-gnuradio] usrp_server code

[Eric Blossom]

On Fri, Nov 07, 2008 at 01:53:11PM -0500, Achilleas Anastasopoulos wrote:
> Hi,
>
> I am looking at the usrp_server code in the trunk and have the following  
> question.
>
> Is there any difference between a tx/rx "port" and a "channel"?
> I see that the usrp_server is always initialized with N_PORTS=4 tx and
> N_PORTS=4 rx ports (total of 8 + one control port), but later on, we  
> only work with d_nrx_chan = d_ntx_chan = 2 tx and rx channels.
>
> My understanding was that ports/channels are in one-to-one  
> correspondence. So I thought that N_PORTS is the "maximum" number of  
> ports/channels that the server can handle.
> In that case, I would expect that
> the parameters d_nrx_chan, d_ntx_chan are given to the constructor and  
> used accordingly...
> The picture is more obscure considering that there is also a
> D_MAX_CHANNELS = 16 in the usrp_server.h file...
>
> What am I missing?
>
> Thanks
> Achilleas

The actual number of channels available depends on the fpga image
loaded.  I'm not sure how Geoerge is handling that, or whether he
provides a method to query it.

Eric