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【标准】计算机视频显示标准介绍(英文) - Multicolor Graphics Adapter (MCGA)

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【标准】计算机视频显示标准介绍(英文)
MDA
HGC
CGA
EGA
PGC
8514
VGA
MCGA
SVGA
XGA
SXGA
QXGA
HXGA
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Table of Computer Display Standards
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Multicolor Graphics Adapter (MCGA)

MCGA shipped first with the IBM PS/2 Model 25 in 1987. MCGA graphics were built into the motherboard of the computer. As a sort of step between EGA and VGA, MCGA had a short life and was shipped with only two IBM models, the PS/2 Model 25 and PS/2 Model 30 and fully discontinued by 1992. The MCGA capabilities were incorporated into VGA. Note: Some say that the 256-color mode of VGA is MCGA but, to be accurate, no MCGA cards were ever made; only the two IBM PS/2 models indicated had true MCGA chips. The 256-color mode of VGA, while similar, stands alone as part of the VGA specification.

The specific MCGA display modes included:

  • All CGA modes (except the text mode that allowed connection of the MDA (model 5151) monitor).
  • 640x480 monochrome at a 60 Hz refresh rate.
  • 320x200 256-color at a 70 Hz refresh rate. The 256 colors were chosen from a palatte of 262,144 colors.

Like the other IBM standards, clone makers quickly cloned VGA. Indeed, while IBM produced later graphics specifications as we'll see below, the VGA specification was the last IBM standard that other manufacturers followed closely. Over time, as extensions to VGA appeared, they were loosely grouped under the name Super VGA.