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Installing Xtium2-CL MX4
Xtium2-CL MX4 User's Manual
Configuring Sapera
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
‘CorMem’
driver default memory setting while the
Allocated
value
displays the
amount of contiguous memory allocated successfully. The default values will generally satisfy the
needs of most applications.
The
Buffers Allocation (Legacy) and (64-bit)
value determines the total amount of contiguous
memory reserved at boot time for the allocation of dynamic resources used for frame buffer
management such as scatter-gather list, DMA descriptor tables plus other kernel needs. We
recommend using the
64-bit
choice for the Xtium2-CL MX4 in order to reserve this memory
anywhere in PC memory and not just limited to the 1
st
4GB of physical memory as would be the
case using the
Legacy
one.
Adjust this value higher if your application generates any out-of-memory error while allocating host
frame buffers or when connecting the buffers via a transfer object. You can approximate the worst-
case scenario amount of contiguous memory required as follows:
•
Calculate the total amount of host memory used for one frame buffer
[number of pixels per line x number of lines x 2 (
if buffer is 10/12/14 or 16 bits
)].
•
Provide 200 bytes per frame buffer for Sapera buffer resources.
•
Provide 64 bytes per frame buffer for metadata. Memory for this data is reserved in chunks
of 64kB blocks.
•
Provide 48 bytes per frame buffer for buffer management. Memory for this data is reserved
in chunks of 64kB blocks.
•
For each frame buffer DMA table, allocate 24 bytes + 8 bytes for each 4kB of buffer.
For example, for a 120x50x8 image:
120x50 = 6000 = 1.46 4kB blocks -> roundup to 2 4kB blocks.
Therefore 24 bytes + (2 * 8 bytes) = 40 bytes for DMA tables per frame buffer.
