GPIB and VISA Problem

[Jeorainc]

Hi,

I am writing program to communicate with Keithley 4200.  I have downloaded the instrument driver.

When I used the Check 4200 ID.vi, the GPIB write had an error with error code was 7.

However, when I changed the GPIB write to VISA write, the error did not happen.

Why this happen?

Attached are the graph of block diagram, one was using GPIB write, another was using VISA write.

Thanks

[smercurio_fc]

Error 7 is a "Nonexistent GPIB interface". What are you setting the VISA resource name to?

[aywl17]

The VISA resource name is GPIB0::17::INSTR.  

The error was shown when using GPIB write.  It is fine when VISA write was used.

[Dennis_Knutson]

What GPIB card are you using? Is it from NI?

[aywl17]

I am using GPIB-USB-HS from NI.

[Albert.Geven]

And what was the GPIB string you used?

[aywl17]

The string is "ID" and the address is 17.

[Albert.Geven]

use simply 17 in the string, and it should work.

Why did you put ID in the string?

[aywl17]

Sorry.  I misunderstood your questions.  I have already using 17 in the string.  ID is the data I want to write to the instrument.

[Albert.Geven]

The only thing I can guess now is that the bus already was occupied by another program or max or hyperterminal or maybe gpib itself,

Do you close the session?