American Megatrends Super Voyager LPX, User Manual

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Chapter 4 VGA BIOS
112
VGA BIOS INT 10h Inquiry Functions
, Continued
Function 12h Subfunction 9Ah Inquire User Options
This function returns the current status of the user options.
Input:
AH = 12h
BL = 9Ah
Output: AX = Contains the following options:
Bit 15 Reserved
Bit 14 Vertical monitor type 640x480 frequency
(VGA refresh)
Bits 13-11 Reserved
Bit 10 0 Force 16-bit operation
1
Force 8-bit operation
Bits 9-7 Reserved
Bits 6-5 Vertical monitor type maximum
resolution
Bits 4-2 Monitor Type (Horizontal)
Bits 1-0 Reserved
BX = Reserved
CX = Contains the following options
Bits 15-13 Vertical monitor type 1024x768
frequency
Bits 12-11 Vertical monitor type 800x600 frequency
Bits 10-6 Reserved
Bits 5-4 Vertical monitor type 1280x1024
frequency
Bits 3-0 Reserved
DX = Reserved