visa problem with old instrument

[mr.knd]

Hallo!

I have a Problem with an old Jobin Yvon HR320 Monochromator which I try to access via VISA. Sadly I have no manual for the instrument. My task is, to convert an old VEE-Programm to Labview 7.0 using an agilent PCI GPIB-card. In VEE the monoc. is initialised with a string "248222 " which returns a B if not initialised yet. This works fine with LV. The next step is to send "O2000" as a string then, in VEE, Write Byte "0" and at last a blank. This should return a character "f". In LV I don´t know how to write the zero as byte. The VEE I/O busmonitor shows that there is a differenc if I write the zero as text or as byte. Maybe someone knows a solution for this problem?

Thanks
C.Kandler

P.S. I read a lot about the ni-spy, but I can´t find it in labview. Is there a posibility to download this tool?

[LuI]

C.,

a LabVIEW string is more like a Pascal string, rather than a C string.
To write binary data you should create a string constant or control, right-click on it and choose "'\' Codes Display" or "Hex Display". Now you can enter a null Byte as '\00' or '00' (without the quotes, of course), depending on what type of display mode you have chosen. The first mode ist easier to combine with normal printabel text, whereas the latter is better for binary strings.

NI Spy was installed here in C:\Program Files\National Instruments\NI Spy\NISpy.exe. It might be a component with higher level versions of LabVIEW, not with the base version.
But if you create probes you could as well debug your app without NISpy.

HTH and
Greetings from Germany!
--
Uwe

[mr.knd]

Hi Uwe!

Thanks alot! I´ll try this tomorrow with new hope for my VI:)!

[D]

Hello,

I unfortunately cannot help with the VEE program, but I was wondering if you could send me a brief description of how you got your Agilent GPIB card to work with LabView. I can't even get MAX to recognize it as a VISA.

Thanks!

D