TRIGEM 386X, Operation Manual

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The personal computer industry has established several video
controller resolution and color standards. Some of these are
described below.
- Hercules Graphics Compatible (HGC):
HGC boards have become the video controller-of-choice
for basic personal computer video display monitor systems.
Providing dot resolutions up to 720x350, HGC boards
display good quality text and graphics, while using
shading to accommodate color software.
- Color Graphics Adaptor (CGA):
The original CGA boards featured very low resolution,
typically 320
x
200. This was because they were originally
intended home computers that were used for advanced
video games. Recently, however, CGA resolution has
been improved to 640
x
200. With the higher resolution,
CGA has gained acceptance in the office environment.
By using colored text screens and low-level graphics, a
number of software packages have been made easier to
use.
- Enhanced Graphics Adaptor (EGA):
EGA video systems provide high resolution (640
x
350
maximum) color graphics capabilities. These monitor
systems are often used in computer-aideddesign
workstations and other software applications requiring a
larger number of on-screen colors than CGA controllers
can provide.
- Video Graphics Array (VGA):
Recently, a new video standard has emerged to take
advantage of the features of the multi-sync monitors.
Providing up to 720x400 dot resolution, these systems
have been used in applications that require the highest
possible video resolution, such as desktop publishing,
computer-aideddesign (CAD/CAE), and broadcast quality
computer graphics.
C-2
Video Monitor Systems