Trying to get GPIB communications working with VB.

[sfb]

I am trying to get GPIB (IEEE-488) communications working between a VB 6.0 program and a GPIB-enabled device.  An NI PCI-GPIB card is installed in the machine, which is running Windows XP.  The driver that is installed and being used is the nipalk.sys driver supplied with the NI-488.2 software.  The GPIB Explorer program, supplied with the NI-488.2 software, sees the device and assigns an address.  When I use that address in the program, GPIB commands that I send work, which is to say that the device responds.  For example, *IDN? works.  However, when I try to send through a device specific command, there is always a timeout error that results from the operation.  The device says it is in listening mode, but it is not responding to its own commands.  Is there anything I am missing with regards to GPIB programming that is causing this?  Are there any ideas I can try for troubleshooting this problem?  Thanks ahead of time for any assistance.

Steve...

[Dennis_Knutson]

First, you should debug all of your commands in MAX. It's just a lot easier there to check syntax of the commands you are issuing. Second, a timeout error is usually associated with a read. Is that the case with your program or do you get timeout errors with a write. What are the actual commands you are sending when you get the error and what is the instrument you are using?