No GPIB connection, but visible in MAX

[JBanting]

The device is visible in MAX, but I am unable to communicate with it, either by using the 'Communicate with Instrument' or the 'VISA Test Panel'.

This seems slightly sporadic, as I have once or twice been able to connect and send a successful ID query (It's too old for *IDN? ...). However, even if I reach this point I either then get error 0: not able to connect to device/driver or error 6: timeout within Labview, and then I am unable to do anything in MAX after that point.

I have tried disabling timeout, switching cables, turning everything off and on again all to no avail.

This is very frustrating as with my standard setup I have not changed any VI's, settings, cables or anything since it was working fine earlier.

Cheers for any input. 

[nyc_(is_out_of_here)]

Which GPIB adapter are you using?

[Dennis_Knutson]

And what's the instrument? Something so old that it doesn't support the idn query may have a hardware failure. Have you tried replacing it with a spare?

[JBanting]

Sorry, I forgot to mention, its an NI GPIB-USB-HS.

I also have the same problem (minus any instances of error 0) with an EG&G 5210 Amplifier.

[JBanting]

It seems like I accidentally deleted the first paragraph of my initial post, the instrument I'm currently having problems with is an EG&G 5207 Lock-In Amplifier.

[nyc_(is_out_of_here)]

For older instruments you may have to resort to NI-488.2

I had some old HP counters that did not "play nice" VISA.

[JBanting]

Sure, I'll see what I can find and if it helps at all.

Interestingly, today the 5210 connected fine and I was able to test some new code and everything worked perfectly...