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Installing X64 Xcelera-HS PX8
X64 Xcelera-HS PX8 User's Manual
Configuring Sapera
Viewing Installed Sapera Servers
The Sapera configuration program (Start • Programs • Teledyne DALSA • Sapera LT •
Sapera Configuration) allows the user to see all available Sapera servers for the installed
Sapera-compatible boards. The System entry represents the system server. It corresponds to the
host machine (your computer) and is the only server that should always be present.
Increasing Contiguous Memory for Sapera Resources
The Contiguous Memory section lets the user specify the total amount of contiguous memory (a
block of physical memory, occupying consecutive addresses) reserved for the resources needed for
Sapera buffers allocation and Sapera messaging. For both items, the Requested value dialog
box shows the driver default memory setting while the Allocated value displays the amount of
contiguous memory that has been allocated successfully. The default values will generally satisfy
the needs of most applications.
The Sapera buffers value determines the total amount of contiguous memory reserved at boot
time for the allocation of dynamic resources used for host frame buffer management such as
scatter-gather list, DMA descriptor tables plus other kernel needs. Adjust this value higher if your
application generates any out-of-memory error while allocating host frame buffers. You can
approximate the amount of contiguous memory required as follows:
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Calculate the total amount of host memory used for frame buffers
[ number of frame buffers • number of pixels per line • number of lines • (2 - if buffer is 10
or 12 bits) ].
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Provide 1MB for every 256 MB of host frame buffer memory required.
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Add an additional 1 MB if the frame buffers have a short line length, say 1k or less
( the increased number of individual frame buffers requires more resources ).
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Add an additional 2 MB for various static and dynamic Sapera resources.
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Add the amount of memory needed for DMA tables using the formula (Sapera 7.10 and up):
[ number of frame buffers • number of lines • 16 • (line length in bytes / 4kB)].
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Test for any memory error when allocating host buffers. Simply use the Buffer menu of the
Sapera Grab demo program (see
" on page 39
) to allocate the
number of host buffers required for your acquisition source. Feel free to test the maximum
limit of host buffers possible on your host system – the Sapera Grab demo will not crash
when the requested number of host frame buffers cannot be allocated.
Host Computer Frame Buffer Memory Limitations
When planning a Sapera application and its host frame buffers used, plus other Sapera memory
resources, do not forget the Windows operating system memory needs.
A Sapera application using the preferred scatter gather buffers could consume most of the
remaining system memory, if a large number of frame buffers are allocated. If using frame buffers
allocated as a single contiguous memory block, Windows will limit the allocation dependent on the
installed system memory. Use the Buffer menu of the Sapera Grab demo program to allocate host
buffer memory until an error message signals the limit allowed by the operating system used.
Contiguous Memory for Sapera Messaging
The current value for Sapera messaging determines the total amount of contiguous memory
reserved at boot time for messages allocation. This memory space is used to store arguments
when a Sapera function is called. Increase this value if you are using functions with large
arguments, such as arrays and experience any memory errors.
