Prologix USB/GPIB Talk and Listen

[KazkekA]

Hi I have a prologix USB/GPIB controller that I aim to use to control several different instruments. Currently I followed another post that seemed to have the correct method of talking to an instrument.

http://forums.ni.com/t5/Instrument-Control-GPIB-Serial/Communication-with-a-Keithley-195A-through-a-...

also this one

http://forums.ni.com/t5/Instrument-Control-GPIB-Serial/GBIP-Control-using-prologix-usb-converter/m-p...

Unfortunately I am unable to even send a basic *IDN? command to the instrument. I've tried talking to several different instruments to make sure that it wasnt a problem with an instrument and I've had no luck with any of them.

Ive combined the linked posts solution with the Prologix Sample that is also linked in his post to create a vi to just send an *IDN? command. I should also say that I could not get the Prologix Sample VI working so this is what lead to me modifying their vi. All drivers are installed from ftdchip and I see the USB Serial Port (COM3) installed in my device manager.

I can get the prologix USB/GPIB to switch from Listen to Talk but it seems impossible to get it to switch back to Talk. Even if I just send a ++addr 0 command. Im not sure what I need to do to get the *IDN? command to send to the instrument.

Thanks

[nyc_(is_out_of_here)]

It is not a National Instruments product. Why are you posting here????

Go talk to Prologix. You bought their product.

[KazkekA]

I know that it is not a NI product, but the program that I am using to talk to it is an NI product. If I were to go to Prologix they could nearly do the same thing and say that "Labview is not a prologix product so why not go ask them how to program in it."

[Dennis_Knutson]

But you are not limited to testing communication with just LabVIEW. Try using a basic terminal emulation program such as hyperterminal. That is probably the same advice you would get from prologix.

[richjoh]

Have a look at the attached VI, it uses the Prologix GPIB-Ethernet converter. Probably the reason why it doesn't work for lots of users is the TCP/IP Socket Class must be manually selected on your VISA Ctrl/Constant Handle, (the default is I/O Session INSTR but NI MAX knows nothing about Prologix). Moreover and beyond the point, you can send the instrument via Prologix a raw TCP/IP packet and get a response but that doesn't give you a VISA handle to use already written drivers.

Rich J

Labview version 2014!

[richjoh]

Hmmm, something not quite right, my driver VI hang whenever I use the TCP/IP SOCKET. So maybe it is a bad deal... still working on it.

[richjoh]

It appears no trouble on Visa Send but VISA Recieve would time out no matter the setup of the Prologix GPIB - Ethernet. you need some code modification it appears to make this work. All transmission (VISA Sends) must be appended with line-feed character and VISA property "Message Setting : Suppress End Enable" must be set to False (btw TCP socket default is True). Once I did this, VISA Recieve stopped timing out. All other VISA property setting had no change.

Now if you have driver code (e.g. Agilent E44XX Spec An) it likely the VISA Send VIs do not include the explicit Line Feed character.

I'm wondering if this a bug on Prologix adapter? Per Prologix Configuratoin Tool or in the manual is strips all end characters and put a termination character on end (but no mention of what happens on Receive from Instrument side). Can a Prologix person tell us.

Just ordered an NI GPIB enet-1000 or whatever its called.

[Dennis_Knutson]

This is not the prologix site so why would a prologix person answer here?

[richjoh]

I noticed a Prologix employee posting info on another thread regarding there product. So not totally oiut of the question. This thread is about inferfacing there product using LV and I don't see a Prologix forum of there own.

[Dennis_Knutson]

There is in fact a contact page that you can use.