Re: [Discuss-gnuradio] Transmitting bursts with GRC by inserting SOB and EOB

[Martin Braun]

On 10/21/2014 03:53 PM, Frederik Wing wrote:
> Hi Marcus,
>>>> I cannot believe that there is no solution to it since the "tags_demo"
>>>> application shows that it is indeed possible. :-/
>> that makes the two of us! I didn't get that when using tags_demo, you're
>> not seeing the carrier that you use tags_demo; as far as I understood,
>> your application does exactly the same, sending bursts with sob/eob tags?
> 
> That's right. tags_demo works perfectly. No carrier in between the bursts.
> The flow graph I posted before sends exactly one burst with SOB and EOB
> tags. The only difference to tags_demo I could recognize so far is that
> I don't assign time stamps to the samples. But this shouldn't be a
> problem, should it?

Hm, it might. Give it a shot -- there might be some interaction between
the way GNU Radio handles the time spec and what UHD expects.

To reiterate on an earlier part of this thread, if you only see a single
'U', then GNU Radio/UHD *are* respecting the eob/sob tags, albeit in a
slightly buggy way (there should be no U). If the tags weren't
respected, you'd see lots and lots of U's between bursts. Although this
might also be related to the time stamps.

Cheers,
M