Setprivilege (window, priv), Unmapvxiaddress (window), Vxipeek (addressptr, width, value) – National Instruments NI-VXI User Manual

Page 71: Vxipoke (addressptr, width, value)

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Chapter 3 Software Overview

© National Instruments Corporation

3-33

NI-VXI User Manual

SetPrivilege (window, priv)

SetPrivilege

sets the VXI/VMEbus windowing hardware to access

the specified window with the specified VXI/VMEbus access privilege.
The possible privileges include Nonprivileged Data, Supervisory Data,
Nonprivileged Program, Supervisory Program, Nonprivileged
Block, and Supervisory Block access. The application must have
Owner-Access Privilege to the applicable window for this function to
execute successfully. Notice that some platforms may not support all of
the privilege states. This is reflected in the return code of the call to

SetPrivilege

. Nonprivileged Data transfers must be supported

within the VXI/VME environment, and are supported on all hardware
platforms.

UnMapVXIAddress (window)

UnMapVXIAddress

reallocates the window mapped using the

MapVXIAddress

function. If the caller is an Owner-Privilege accessor

(only one is permitted), the window is free to be remapped. If the caller
is an Access-Only Privilege accessor, the window can be remapped
only if the caller is the last Access-Only accessor. After a call is made
to

UnMapVXIAddress

, the pointer obtained from

MapVXIAddress

is

no longer valid. You should no longer use the pointer because a
subsequent call may have changed the settings for the particular
window, or the window may no longer be accessible at all.

VXIpeek (addressptr, width, value)

VXIpeek

reads a single byte, word, or longword from a particular

address obtained by

MapVXIAddress

. On most platforms using

C language interfaces,

VXIpeek

is a macro. It is recommended,

however, that you use

VXIpeek

instead of a direct dereference of the

pointer, as it supports portability between different platforms and
programming languages.

VXIpoke (addressptr, width, value)

VXIpoke

writes a single byte, word, or longword to a particular

address obtained by

MapVXIAddress

. On most platforms using

C language interfaces,

VXIpoke

is a macro. It is recommended,

however, that you use

VXIpoke

instead of a direct dereference of the

pointer, as it supports portability between different platforms and
programming languages.

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