Chapter 6 NI-VXI Configuration Utility
PCI-MXI-2 for Linux 6-18 ni.com
Window Size
The amount of space you can allocate for the user window is system
dependent. You can use the Size control to select the size of the user
window (minimum of 4KB, maximum of 2 GB). The more you increase
the size of the user window, the larger the window you can mapin
MapVXIAddress().
You also can disable this option. Disabling the user window causes the
PCI-MXI-2 to request the minimum amount of address space on the
PCIbus. With the window disabled, you will be unable to perform any
low-level function calls such as VXIpeek(), VXIpoke(), and
MapVXIAddress().
It is recommended to have a user window of at least 64KB, and the default
setting for the user window is set at this value. If you are going to be
initiating transfers to a wide variety of addresses in both A24 and A32, you
should increase the size of the user window. Any change you make to the
size of the user window requires that you reboot your computer.
The size of the driver window, however, is system defined and is not user
configurable.
Note Neither the user window nor the driver window can be placed below 1MB with the
Linux NI-VXI driver. Therefore, the Place below 1MB option and the Window Base
option will always be disabled.
Expansion ROMUse the Enable expansion ROM control to enable or disable the PCI
expansion ROM. The expansion ROM is enabled by default. It is
recommended to retain the default setting. This option is included in
vxiedit in case future versions of the PCI-MXI-2 do not implement a PCI
expansion ROM.