discuss-gnuradio
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Discuss-gnuradio] usrp_siggen.py underruns


From: Dominik Auras
Subject: Re: [Discuss-gnuradio] usrp_siggen.py underruns
Date: Wed, 11 Feb 2009 22:26:25 +0100
User-agent: Thunderbird 2.0.0.19 (X11/20090105)

Hi!

An additional note: using usrp_siggen.py with sine, const and uniform at 8 MHz bandwidth actually works. It is unlikely that my EHCI controller does not support 32 MB/s on transmit.

Could this be a timing problem? I mean, that the data is generated very fast, but then the generator waits, e.g. because the buffer is full. Does the double buffering of the TPB scheduler work as supposed? Using STS scheduler with usrp_siggen didn't change anything.

Summary:
The application supports 12.5 complex MS/s (100 MB/s) if using USRP2, but can't sustain 8 complex MS/s with USRP1, even though usrp_siggen.py does support 8 MS/s with the generators sine,const and uniform on the USRP1 (and test_usrp_standard_tx estimates an achievable rate of 32 MB/s). Furthermore, this behavior shows up on 2 different machines.

Do you have an idea how I could benchmark the application, e.g. to characterize the stream timing in front of the USRP?

Best regards
Dominik




reply via email to

[Prev in Thread] Current Thread [Next in Thread]