[Discuss-gnuradio] Re: reporting control/status responses for inband signaling?

[George Nychis]

Brian Padalino wrote:
> I should note here that the USRP doesn't care which application on the
> host requests the different actions, which is probably why we have the
> fixed channel of 0x1f.  The USRP is simply the endpoint.

Definitely, I agree with this.

> Looking at the payload of the control channel, any of the op codes
> that write something and then have the USRP reply back seem to have an
> RID within them to determine where to send things back.
>
> This is probably what should be inserted/stripped by the usrp_server
> to figure out which application receives the reply.
>
> I can see this working where the Application requests something (ping
> perhaps?) and sends the ping request to the usrp_server.  The
> usrp_server constructs the packet with the next available RID
> (probably just some incremental counter mod 64, or if you don't expect
> one application to have multiple outstanding commands, just a unique
> number for each application which is reused - just ideas and you know
> this more than I would).  After the USRP then processes the command
> and sends the reply back, the usrp_server will read the RID field of
> the received packet and forward the packet (minus the RID) back to the
> Application.
>
> I could be missing it just as much as you did, but what do you think 
> about that?

I think you're right on this, all of the commands which have a response 
have an RID.  I'm going to go with the incremental counter mod X because 
I can imagine instances where one app could have multiple outstanding 
commands.  It's unlikely, but for safety sake.

Thanks for the response and insight, I was just going to 'broadcast' all 
responses to all applications for now... but now I can actually code it 
correctly ;)

- George