Chapter
6 NI-VXI
Configuration
Utility
©
National Instruments Corporation
6-7
VXI/VME Shared RAM Size
This field indicates the amount of RAM (in bytes) that is shared in either
A24 or A32 space. This determines the
total
shared RAM size, which is
then divided into two equal halves that you can set up independently of
one another.
Note
When the Address Space field is in the default setting of A16 only, this field is
ignored.
Shared RAM Pool
This field indicates the size of memory (in kilobytes) that is allocated at
startup. This memory is used by the lower/upper half window when the
Memory Select
control—accessible through the Advanced popup
field—is set to
System memory
.
The following table indicates how the
Shared RAM Pool
relates to the
VXI Shared RAM Size
depending on the setting of the
Memory Select
control for the upper and lower half windows.
The shared RAM pool is used by
VXImemAlloc()
function calls. For
information on the
VXImemAlloc()
function, refer to the
NI-VXI User
Manual
and the
NI-VXI Programmer Reference Manual
.
Memory Range
Default Value
0 to 65535 KB
0 KB
Lower Half
Window
Upper Half
Window
Shared RAM Pool
(Window)
System memory
System memory
Equal to VXI/VME
Shared RAM Size
System memory
Onboard memory
Half the VXI/VME
Shared RAM Size
Onboard memory
System memory
Half the VXI/VME
Shared RAM Size
Onboard memory
Onboard memory
0