parallel poll with gpib

[wantai]

Hello,

first and foremost sorry for my bad english 😉 hope you understand anyway...
i've tried to configure a simple parallel poll routine on gpib bus.
i followed this instruction : docs.jach.hawaii.edu/JCMT/gpib/gpib_appnote5_polling/gpib_appnote5_polling.pdf
i've tested the parallel poll with one single device , connected to my pc-interface, but i had no success..

//reset
SendIFC(0);
//parallelpoll configure
Sense = 0;
PPollConfig(0,Deviceadress, Dataline, Sense);
//execute parallelpoll
PPoll(0, Response)

I set the Sense to 0, so the device should assert the dataline, if the IST value is equal 0.
I thought this should be pretty nice for testing ..
But the Response is always 0..

Is it possible that not every device could be configured for parallel polling ?
anyone has an idee ?

greatings,
wantai

[JasonSmith]

Hi wantai,

Parallel polling is an optional component in the IEEE specification for GPIB.  This means that you will need to check your instrument documentation to find out whether or not it can support the parallel poll functionality--many instruments do not.

Due to the optional nature of parallel polling, and the complexity of setting it up, most systems utilize serial polling.  While parallel polling can be slightly faster, the time it takes to perform a serial poll is usually not an issue with modern systems.  I would recommend that you look into using serial polling in your application, as it will be easier to find examples and get help here on the forums, since more people utilize it.

If you need to use parallel polling, confirm with your documentation whether it is supported, and we can go from there.

Jason S.
GPIB & Serial
National Instruments