You can find some information from the "VISA Run-time Engine Version 3.2 for Windows 2000/NT/XP" Readme.txt file:
http://digital.ni.com/softlib.nsf/websearch/C0CDC738994FCBC886256EEB004E9BB3?opendocument
To save you some time though:
NI-VISA 3.2 IMPROVEMENTS AND BUG FIXES
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Enabling the NiVisaTulip Passport would cause applications to crash on exit.
This is fixed.
For a USB RAW resource, calling viEnableEvent on VI_EVENT_USB_INTR with the
VI_HNDLR mechanism would cause a crash when the first interrupt arrived.
This is fixed.
Added support in MAX for the standard Export and Import wizard. For NI-VISA,
this allows you to transfer the VISA aliases and driver settings.
Calling viPrintf on a remote VISA session would return VI_ERROR_IO instead
of VI_ERROR_RSRC_LOCKED when the remote resource was locked. This is fixed.
The VISA Interactive Control utility (VISAIC) now displays an error message
box when viFindRsrc returns an error.
For a PXI INSTR resource, calling viDisableEvent and then viWaitOnEvent would
cause a crash. On Windows, the application would exit; on LabVIEW RT (both
Phar Lap ETS and RTX), the system would need to be rebooted. This is fixed.
The NI-VISA COM API now supports PXI (INSTR, MEMACC) and USB (INSTR, RAW).
Right-clicking on a PXI chassis in MAX now provides the option to open a
VISA session to that PXI BACKPLANE resource.
Fixed various issues in MAX related to changing the IP address of a remote
VISA system.
Calling viParseRsrcEx would in some cases output the resource class using
the same case you used in the resource string in the input parameter. The
output parameter should always be uppercase. This is fixed.
For a Serial INSTR resource, calling viGetAttribute on VI_ATTR_ASRL_WIRE_MODE
would always output -1 if you hadn't yet set the mode for the given resource.
Now if you have NI-Serial 1.6 or higher installed with supported hardware,
it will output the default configured state rather than -1. Otherwise it
will still output -1. Note that NI-Serial 1.6 does not implement this
feature on all currently supported NI RS-485 controllers.
