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From: "james " <jimwalsh142@hotmail.com>
Newsgroups: comp.soft-sys.matlab
Subject: Problem reading data from Tektronix oscilloscope
Date: Tue, 8 Dec 2009 20:14:02 +0000 (UTC)
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Dear all,

I have a Tektronix DPO4000 series oscilloscope connected to my PC via USB. I'm using the Instrument Control Toolbox and have followed the guide 'USING MATLAB WITH A DPO4000 AND MSO4000 SERIES OSCILLOSCOPES' provided by Tektronix. All works as expected and I am able to save waveform data from each channel on the scope using the 'readwaveform' function.

For my application I need to save 100,000 data points, I have set the record length on the scope to 100,000 yet when I read the data in to MATLAB via USB I only get the first 10,000 points. When I save the data directly on the scope I get the full 100,000 points so I know that's OK. After a little digging I thought that perhaps the input buffer is too small, consequently I have changed it's size to 250,000, yet I still only get 10,000 points! Any ideas??

Thanks,

Jim.