How to transmit synchronously with timestamp using VRT code

GNU Radio
1

Hi All,

I am trying to understand how to use the vrt code. I want to transmit a
burst. For the first vrt packet I use

hdr.header = VRTH_PT_IF_DATA_NO_SID | VRTH_START_OF_BURST |
VRTH_TSI_OTHER;

for the “middle” vrt packets I use

hdr.header = VRTH_PT_IF_DATA_NO_SID;

and for the “final” vrt packets

hdr.header = VRTH_PT_IF_DATA_NO_SID | VRTH_END_OF_BURST.

Is this the correct (it doesn’t really seem to work the way I want).

BR/
Per

2

Quoting Per Z. [email protected]:

hdr.header = VRTH_PT_IF_DATA_NO_SID;

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It seems to work now. The change I made was to reduce the time that
the data waits to be transmitted from twenty to ten seconds. I could
imagine that this has something to do with some timeout.

BR/
Per

3

If your packets are too large, there is some fragmentation logic that
also plays with the burst flags. You may be seeing this fragmentation
within the usrp2 driver at work. Look inside the usrp2_impl.cc in the
tx_raw method.

-Josh