American Megatrends Super Voyager LPX, Руководство пользователя

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Super Voyager LPX ISA Motherboard User's Guide
Super VGA Functions,
Continued
Function 01h Return Super VGA Mode Information , cont'd
ModeInfoBlock Fields
Field Description
ModeAttributes Describes certain important characteristics of the video mode.
Bit 0 specifies if this mode can be initialized in the present video
configuration. This bit can be used to block access to a video mode if it
requires a certain monitor type and the monitor is not connected.
Bit 1 specifies whether extended mode information is available. This
information is required in SVGA INT 10h BIOS Extension v1.2 and
later.
Bit 2 specifies if the system BIOS supports output functions like TTY
output, scroll, pixel output etc. in this mode. The BIOS should support
output functions. The field is defined as follows:
Bits 15-5 Reserved
Bit 4
Mode type
0
Text mode
1 Graphics mode
Bit 3 Monochrome/color mode (see below)
0
Monochrome mode
1 Color mode
Bit 2 Output functions supported by BIOS
0
Output functions not supported by BIOS.
1 Output functions supported by BIOS.
Bit 1 Extended information available
0
Extended mode information not available.
1 Extended mode information available.
Bit 0 Mode supported in hardware
0
Mode not supported in hardware.
1 Mode supported in hardware
Monochrome modes have their CRTC address at 3B4h. Color modes
have their CRTC address at 3D4h. Monochrome modes have attributes
in which only bit 3 (video) and bit 4 (intensity) of the attribute
controller output are significant. Therefore, monochrome text modes
have attributes of off, video, high intensity, blink, etc. Monochrome
graphics modes are two plane graphics modes and have their CRTC
address at 3D4h, are color modes with one bit per pixel and one plane.
The standard VGA modes 06h and 11h are color modes. The standard
VGA modes 07h and 0Fh are monochrome modes.
BytesPerScanline Specifies how many bytes each logical scanline consists of. The logical
scanline could be equal to or larger than the displayed scanline.
WinAAttributes
WinBAttributes Describe the characteristics of the CPU windowing scheme, such as if
windows exist and are readable and writable, as follows:
Bit 7-3Reserved
Bit 2
Window writable
0
Window is not writeable