Display Section - Matrox Orion Installation And Hardware Reference

Underlay frame buffer
surface
Overlay frame buffer
surface

Display section

To drive the display section, Matrox Orion uses the Matrox
MGA-G400 graphics display controller. It has a 128-bit wide
memory interface with the AGP or PCI bus and stores both
graphics and video data in the 32-Mbyte frame buffer
(SDRAM). The MGA-G400 chip is capable of dynamically
allocating both an overlay and underlay frame buffer surface;
these can be combined by the controller to display a live video
window on your Windows desktop with non-destructive
annotations. A 256 Kbyte Flash Memory is used to
permanently store the Video BIOS.
Although Matrox Orion has an on-board MGA-G400, the
Matrox Orion architecture can only support a true color (32-bit)
image display with a 32-bit color overlay at a maximum
resolution of 1280x1024.
The underlay frame buffer surface is typically used to display
video data. The size of this surface is the same size as the image
selected to the display, and its data format is YUV16 (YUYV)
for color buffers, and 8-bit monochrome for monochrome
buffers.
The overlay frame buffer surface is used for both displaying the
desktop, and overlaying non-destructive graphic annotations
on your image. The size of this surface is the same as the
desktop, and can only be displayed in 8-bit monochrome or
32-bit color (BGR32 packed).
See Chapter 4: Matrox Display Properties and Matrox
PowerDesk to set your display properties.
Display section 39