USRP v2 TX Bandwidth

GNU Radio
1

Is there a status indicator in the USRP2 C++ interface that flags
underflows? I am trying to push samples (using the std::complex<int16_t>
type) to the USRP2 at an interpolation factor of 4. It seems to be
working, but I require hard evidence that I am not underflowing.

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2

Gregory W. Heckler wrote:

Is there a status indicator in the USRP2 C++ interface that flags
underflows? I am trying to push samples (using the std::complex<int16_t>
type) to the USRP2 at an interpolation factor of 4. It seems to be
working, but I require hard evidence that I am not underflowing.

The easiest way right now is to monitor the debug serial port. When
there are underruns, it prints “U”. Eventually, we’ll have it reporting
all the way back to the host, but haven’t implemented that yet.

Matt

3

Hi Gregory,

as far as I know there is no indication for underflows while
transmitting which
will print the error directly in the shell. But there is a serial debug
port
placed on the USRP2 board. It will give you a control message in case of
an
underflow.

Cheers,
Christoph

4

I haven’t looked at the usrp2- code for a while, but I think there might
have been
something like the usrp- equivalent of “oU”/“uU”- shell printing.
But that was a while back and it might have changed. If you have a look
in the meta- data there is a field called overrun. But as someone
pointed out all
features that “should” be there are not yet implemented.

Someone more up to date with the current code might correct me/confirm.
//Mattias