Hi Tom,
I appreciate your response and information on setting noutput_items for version 3.6.2. I am not sure if changing the noutput_items or buffer size is going to help at all.
Basically when the data rate is lower than the transmission rate (purposely to eliminate latency), I'm noticing that the USRP is outputing random gaps in my packet of data during some of the underruns. Some of the underruns generate a wider gap between packets (this is good) but some of them generate a gap inside the packet data blocks causing problems. This happens when I am using a 125kHz sampling frequency and the USRP's rate set lower than 1M S/s. However with the USRP at 1M S/s it works fine. My goal is to run the USRP at 250k S/s to reduce processor load.
For the 125k S/s
case and lower
than 1 M S/s USRP rate, if I increase my packet size by a factor of two, the gaps caused by underruns happen only between packets not inside them. The problem is the increase in packet size is not desirable for my application.
The behavior I observed makes me think the issue could be fixed with changing the Nout_items or buffer settings. Any idea if that might be true?
Thank you, Tom
From: Tom Rondeau <address@hidden>
To: Tom Hendrick <address@hidden>
Cc: "address@hidden"
<address@hidden>
Sent: Wednesday, February 6, 2013 2:36 PM
Subject: Re: [Discuss-gnuradio] Changing Nout_items and Buffer Settings for GNURadio 3.6.2