gpib

[ichigo55]

Hello so I have an interesting situation I am attaching a keithley 2000 to my computer through gpib to usb cable. I am trying to connect two of the keithley devices up so that I can get two different temperature readings. However when I implement the code for one of the keithley 2000 it works fine i get a measurement and it gives me what I expect. Where the weird part is when I try it on the second one it does not work same program nothing changed same cable probes and so on. It gives me back the error

1073807339

VISA Read in temper.vi

I also have a second one I try and the machine gives me back error 420 which is query unterminated. I will attach my code so that you can check it out. Any help would be great. I am trying to figure out why it would work for one keithley but not the others.

[Dennis_Knutson]

Is the second instrument detected by MAX? If so, can you use the interactive control to do.an idn? query?

[crossrulz]

My very first though is "Do the two DMMs have the same GPIB address?"  If so, then you will have some major issues.

I'm also pretty sure you have to configure the DMMs to communicate over the GPIB bus.  I want to say that it defaults to serial.

[ichigo55]

That is where the weird part comes in I have even tried to connect just the one device at a time to see if it works where one keithley device works but another wont and I get

error 1073807339

VISA Read in temper.vi

So that is where I am confused on is why it works for one keithley device but not another.

[Dennis_Knutson]

And did you do anything that was suggested?

[pjr1121]

You say you didn't change anything, BUT if the second keithley 2000 has a different GPIB address (which is should in order to use two of them), you must change the program to match.  Also, some keithley models must be switched from default RS232 communication to GPIB on the front panel.  If the keithley 2000 is expecting RS232, it will ignore any GPIB messages.

[ichigo55]

How do you mean change the program to match?

[ichigo55]

So I have a gpib to usb going from my device to the computer. So I am attempting to connect the two keithley through a gpib to gpib cable then have the gpib to usb connected to one of them then go to computer. However it only seems to be seeing the one that is address is sixteen.

[billko]

---

@ichigo55 wrote:

How do you mean change the program to match?

---

You have to know the GPIB address of the second Keithley.  Then you change the resource accordingly.  But let's take a step back...

How much do you know about automated testing?

How much do you know about LabVIEW?

[ichigo55]

I know a little bit about both I have only dove into lab view only over the last few months to create this automated process where I need to keithley devices to take readings I know the address of both but only the one with address sixteen is being seen since that is the primary address of the cable it seems like.