Rastergraf Duros, Руководство пользователя

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Rastergraf
Specifications 2-13
2.5 Verified Display and Capture Modes
The SM731 Graphics Controller is a flexible chip. It supports a single
input capture channel as well as up to two independent outputs. It has
widowing capabilities and a 128-bit high-performance drawing engine.
But, the overall throughput is handicapped somewhat by a 64-bit memory
bus. This section provides some tabulated information about the practical
capabilities of the SM731. These sorts of limitations are common in
graphics chips, but it’s just unusual for a vendor to provide quantified data
to the customers.
Note that this data is empirically obtained. There may be cases where a
format that was observed to be clean might not be with high drawing
engine activity. Special test software was used, not SDL or X Windows, in
order to avoid application software dependencies.
2.5.1 Basic Format Evaluations
Notes:
nn-xx where nn = 640,1024,1280 or 1600 (nn = horizontal resolution)
xx = 8, 16, 24 or 32 (xx = bpp)
Resolutions tested: 640x480, 1024x768, 1280x1024, 600x1200
All modes use 60 Hz vertical refresh rate
Mode
FP in VGA column means FP timing used for VGA out
Mode VP in DVI column means VP timing used for DVI out
-TV in VGA column means scaled TV out used instead of RGB out
Window is 640x488 YUV422; values are N (no), Y (Window only) or CAP
(capture). CAP (capture) is 640x488 NTSC interlaced or 640x480 RGB @ 75Hz
Activity indicates display memory is under test to simulate application accesses
*streaks : the DVI window is VERY sensitive to VGA timing, but the VGA
window is NOT sensitive to the FP timing. *streaks in window : both capture
windows displayed caused major streaking
*Max : maximum vertical refresh rate before snow became apparent
*Max2 : same as *Max, but while capturing 1024x768@75Hz
"Max, Max2 is highest rate without snow or streaks, but capture update is
slowed, which shows on moving video
Green Background means a clean format
Red Background means that a less than clean result was observed
In general, 16bpp mode has MUCH better performance than 32bpp mode. The
DVI video window is very sensitive to the VGA refresh rate. If dual displays are
required, one with a video window, performance is better if it is the VGA video
window. Both displays can not use the same capture data for video window at
higher resolutions - it gets ugly. The highest mode pair that would cleanly display
both video windows was 1024x768x32bpp.