RQS Issue

[d.gelman]

Hello,

My project contains keithleys 2400 sourcemeter (I source) and 2182a nanovoltmeter into LabVIEW under Delta Mode.  The keithley example (2182Delta_LV6.vi) uses a "Wait for GPIB RQS" vi which does something... I have no idea, if someone would be kind enough to explain it.  Sometimes it wouldn't be a bother and my system would work PERFECTLY... but sometimes it would wait the entire timeout (50seconds) and I would get 0s as my output. (naturally the sourcemeter should turn off, but when this problem arises, the sourcemeter stays on after the vi completes).  After my vi completes, I get an error message "GPIB Read in 2182 Read and Display.vi -> 2182DeltaLV6 2.vi")

Also the keithley example uses a flat sequence structure.  I used and built on top of this example and was fed up with the unorganization, so I made each sequence its own subVI.  Now I have this SRQ problem stated above.  Phyiscally, the sourcemeter would just output a couple of triggers of source currrent and would just stop... and remain on without triggering switch polarity (Delta mode).

Attached is the original example (2182Delta_LV6.vi) and my example (2182Delta_LV6 2.vi).

...I am really frustrated with this inconsistancy.

Danny

[d.gelman]

My attachments

[James-D]

Hi Danny,

The Wait for GPIB RQS function is a function that waits for the RQS bit to be asserted on the GPIB device that is located at the "address" input. RQS is a byte located in the status bit of a GPIB and is used to denote which instrument is actually requesting service. Please refer to the article contained at the link below for information on the RQS bit and how it is used with the SRQ command. 

http://digital.ni.com/public.nsf/allkb/577D62CFCEE1EC7886256F1F00813215

It would also be helpful to have a look through the LabVIEW Help documentation to make sure you have addressed the controller and the devices properly. Can you provide a more detailed description of the error you were seeing when the VI was finished executing? Was there a code that showed up in the error dialog? 

Regards,

[d.gelman]

Thanks for clearing it up for me,

I am not too sure why this worked but I removed the line:

:SYST:FAZ ON

after I removed this line my software works as intented...

I am not sure why but I am happy it is resolved,

thank you