We must be talking about different things. If your waveform is 2500
points, and takes 73.5 KB, that works out to 29.4 bytes per point.
Sounds like very high resolution! Even if that waveform was transferred
in some ASCII format, that is still very verbose.
I've never tried to measure the GPIB throughput, but I am fairly certain
that the overall throughput in any case that I've encountered is limited
by the scope itself, and the operation of the scope in terms of its
triggering setup and the signal it is measuring. On some scopes (eg TDS
380), I can swamp it's CPU with GPIB communications, and effectively
cripple its functionality. That is an old scope, and I doubt that modern
scopes would be similarly afflicted. Perhaps the hardcopy function would
be a good case for a throughput test.
Pavel Masloff wrote:
> Hi Rod,
> We have 2500 points per waveform. Our PCs are equipped with COM ports
> only, no GPIB cards. One waveform is 73,5 KB to be exact. The RS232
> connection speed is maximum 19200 Kb/s at maximum. For the time being I
> just want to check whether the experiment went fine, no false
> triggering, etc. In the future, I would like to analyze the waveforms in
> matlab via CA. So this will be handy.
> What is the speed of the GPIB interface on Tek scopes, anyway?
> On Fri, May 4, 2012 at 1:42 AM, Rod Nussbaumer <email@example.com
> Every Tektronix scope I've set up communications with had a 500
> point waveform (as well as some substantially larger ones).
> Presently, I'm acquiring those at 10 waveforms per second (over
> GPIB). Are you sure that would not suffice for you? Is GPIB an
> option? Much much faster.
> --- rod.
> Pavel Masloff wrote:
> A waveform weighs 70kB. 4 waveforms = 280 kB. 280 vs 40. I would
> have to
> wait a couple of minutes till the data is processed. 10-15
> seconds for
> the screen dmp.
> On Thu, May 3, 2012 at 11:13 PM, Mark Rivers
> It may be time to back up a step. Why not transfer the
> themselves, rather than a screen dump? There are others in the
> EPICS community who have already done that for the scopes
> you are using.
> __ __
> Best regards,
> Pavel Maslov, MS
> Controls Engineer at Pulsed power Lab
> Efremov Institute for Electro-Physical Apparatus
> St. Petersburg, Russia
> Mobile: +7 (951) 672 22 19
> Landline: +7 (812) 461 01 01