Tseng Qtec VGA 1024, Руководство по установке

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USING THE
EXTENDED COLOR GRAPHICS MODES
I n t r o d u c e i Qn
Besides the standard VGA/EGA/CGA/MDA/Hercules compatibilities the
Qtec VGA1024 has additional display modes. These new modes are
designed to increase the resolution up to 1024x768 (when using an
IBM 8514, NEC Multisync XL, or other compatible monitor).
This application note describes how to identify an Qtec VGA1024,
how to select the extended color modes from application programs
and how these High Resolution memory maps are organized.
Selecting Extended Color Graphics Modes
The Qtec VGA1024 BIOS supports the following extended modes. The
numbers are in decimal except as noted.
Mode Mode Type Length of Memory Map
37 hex Graphics 128x768 = 98304 = 18000 hex (each plane)
30 hex Graphics 100x600 = 60000 = EA60 hex (each plane)
2E hex Graphics 80x480 = 38400 = 9600 hex (each plane)
The HiRes modes are selected exactly as the standard modes 0-7 and
D-10 are selected:
Place a 0 in register AH to indicate "select mode" function
Place the mode number in register AL
Execute an INT 10 instruction, generating software interrupt
10 hex, which invokes the Qtec VGA1024 BIOS to set the mode.
The above calling sequence should be familiar to anyone who has
ever called the BIOS from assembly language or from a machine-
language driver, and is the standard BIOS interface for video mode
select.
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