Host Interface - Matrox Radient eCL Series Installation And Hardware Reference

Host interface

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Host interface
The Matrox Radient eCL Host interface is capable of high-speed DMA transfers
to or from Host memory. The DMA read and write engines of the Host interface
are capable of performing the transfers without the help of the Host CPU.
Before being transferred off-board, the color space converter and pixel formatter
of the Host interface can convert or format the data.
Matrox Radient eCL uses PCIe technology to communicate with the Host. Under
optimum conditions, Matrox Radient eCL can exchange data with the Host at a
peak transfer rate of up to 2 Gbytes/sec, but can sustain a transfer rate of up to
1750 Mbytes/sec. Optimum conditions include using the board in a PCIe slot
with 8 active lanes, using a 256-byte payload. DMA read and write performances
are chipset and computer dependent, and are slightly affected by the image size
and alignment in Host memory (frame start and line pitch).
The Matrox Radient eCL Host interface actually has four DMA write engines,
which can run in parallel; however, only one of these can use the color space
converter. The total bandwidth still peaks at 2 Gbytes/sec, but the presence of
multiple DMA write engines might help reduce latency.