Re: [Discuss-gnuradio] Clock Sync Problems + Timestamp question

[Douglas Geiger]

On Tue, Oct 20, 2009 at 12:20 PM, Tim Pearce <address@hidden> wrote:
>
> I'm also trying to attach the timestamp data do each sample -- as far as I
> can tell this is sent to give the sample timestamp for the first sample in
> each ethernet frame (then incremented by 1 for each subsequent sample in the
> frame)
>
> I think I have to create a new C++ block based on USRP2_SOURCE_32FC() to
> define a second output stream and connect the rx-metadata::timestamp (which
> is a uint32) to this output -- is this correct or can I access the data
> within a custom (or current) block further down the line somehow already?
>
> Thanks in advance,
>
> Tim
>

One thing to keep in mind: the timestamp increments at the FPGA's
clock (100Mhz), so depending on your decimation you'd be incrementing
at some multiple of that for each sample on the host. You are correct
in that you need a custom version of the source block to pass along
timestamps with each sample.
 Doug

-- 
Doug Geiger
address@hidden