> I have got a Plug&Play instrument driver written in National Instruments
> LabWindows/CVI. I created (also in CVI) a dll out of this driver. I load
> this dll in HP-VEE (3.2) as an I/O PNP instrument. In this instrument I
> call a function that has few parameters including a binary switch with
> VISA values VI_ON and VI_OFF. When I turn things on or off nothing
> happens. All other parameters are changed accordingly to changes made on
> the function panel EXCEPT the binary switch.
VEE will only parse and use the #defines that are defined in your PREFIX.h
file, not all the VISA ones too.
In 4.0 VEE will by default handle VI_TRUE, VI_FALSE, VI_NULL, VI_SUCCESS,
and VI_ERROR even if they're not in your .h file.
So I'd say you need to #define those in your PREFIX.h file. Or, upgrade
to 4.0 and use the standard VI_TRUE and VI_FALSE.
HP VEE engineer