Keithley 2701 cannot read buffer over TCPIP

[happydave]

Hi,

I have some problems to communicate with a Keithley 2701 DMM over TCPIP protocol. (I think) I manage to send commands to the instrument with VISA write, but I do not manage to get a reading from the instrument buffer using VISA read (see attached example program). When the command is sent, the Keithley 2701 beeps and the "talk/listen" sign appears on its display.

I am using the following Hardware and software:

Keithley 2701
Keithley 7702 40 channel multiplexer card
Windows XP

Labview 7.1

National Instruments NI-488.2 for Windows. Version 1.70.Any suggestions what could be wrong?

By the way I also have the same problems running the Keithley 2701 + 77XX example programs.

Thanks!!!

[happydave]

Sorry, attachement were missing...

[Albert.Geven]

Try to download the keithley driver from the instrument driver website from NI
follow this link
http://www.ni.com/devzone/idnet/

search keithley and the 2701

[cymrieg]

I am not a LV expert but the screenshot you have shows a timeout error. I see that you have termchar enabled which is correct for VISA socket connections but I am confused by the value it is showing for the actual termchar. It should be linefeed decimal 10?

[happydave]

Hi,

thanks for replying. I changed the termchar now to linefeed decimal 10, but I still get a timeout error.
I do not really understand how these termchars work. Is there any VISA specialist out there?

Thanks,
David

[cymrieg]

Your latest screenshot shows you sending "*idn?" without the '\n". When sending anything to the 2701 over raw sockets you have to append the "\n" (Linefeed char) and reading you need to enable termchar. The default termchar is linefeed.

Make sure the IoProt is set for 488 strings.

Have you used just the VISA Interactive Control to flush this out?

Can you ping the instrument?

[cymrieg]

PS switch viWrite and viRead to synchronous and not asynchronous