AnsweredAssumed Answered

vrf Hardcopy from an Instrument (TEK-scope TDS200)

Question asked by rsb on Sep 26, 2002
"Ruckert, Wolfgang" <Wolfgang.Ruckert@astrium-space.com> wrote:
> hi all
> who can I read a picture file (.PCX, .BMP or .EPS) in a short time from an
> instrument?
>
> for example: I send to a TEK scope the string "HARDCOPY START" and read
> byte for byte from the scope and save it to a file object. It's very slowly.
>
> I'm searching for a faster and simpler solution

This depends largely on what the scope can do of course, but can
also be dependent upon your program. From your description you are
reading one byte at a time- presumably in a loop that looks for EOF.


This is very slow due to all the GPIB signaling involved. Much faster
to read an entire block but this requires that you know how big the
blokc is. If you're doing screen dump and using BMP or the like the size
should be fixed. If this is the case then figure out the size up front
and then read in the entire block of data at once (1 transaction- no
looping).

Also- couldn't tell from your description, but are you perhaps
reading in a byte at a time in a loop and then writing that byte
to a file in the same loop? If so then you get _really_ slow since
now you have the disk overhead for each byte. if this is the case
read in the entire block of data and then do one file write.

If things are still slow then there isn't likely much you can do
since you're most likley limited by the GPIB speeds.

regards

Stan


--------------------------------------------------------------------------
Stan Bischof  Agilent Technologies  707-577-3994  stan_bischof@agilent.com
--------------------------------------------------------------------------

---
You are currently subscribed to vrf as: rsb@soco.agilent.com
To subscribe send a blank email to "join-vrf@it.lists.it.agilent.com".
To unsubscribe send a blank email to "leave-vrf@it.lists.it.agilent.com".
To send messages to this mailing list,  email "vrf@it.lists.it.agilent.com". 
If you need help with the mailing list send a message to "owner-vrf@it.lists.it.agilent.com".

Outcomes