American Megatrends Super Voyager LPX, User Manual

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Super Voyager LPX ISA Motherboard User's Guide
Super VGA Functions,
Continued
Function 06h Subfunction 00h Select Scan Line Length
This function sets the length of a logical scan line. This function allows
an application to configure a logical video memory buffer that is wider
than the displayed area. Function 07h then allows the application to set
the starting position to be displayed.
Input: AH = 4Fh SVGA Support
AL = 06h Logical Scan Line Length
BL = 00h Select Scan Line Length
CX = Desired Width in Pixels
Output: AX = Status
BX = Bytes Per Scan Line
CX = Actual Pixels Per Scan Line
DX = Maximum Number of Scan Lines
Function 06h Subfunction 01h Return Scan Line Length
Input:
AH = 4Fh SVGA Support
AL = 06h Logical Scan Line Length
BL = 01h Return Scan Line Length
Output: AX = Status
BX = Bytes Per Scan Line
CX = Actual Pixels Per Scan Line
DX = Maximum Number of Scan Lines
The desired width in pixels may not be achievable because of hardware
considerations. The next larger value that accommodates the desired
number of pixels is used and the actual number of pixels usee is returned
in CX. BX returns a value that, when added to a pointer into video
memory, points to the next scan line. This function is also valid in text
modes. In text modes the application should find the current character
cell width through INT 10h Function 01h Return Super VGA Mode
Information, multiply that times the desired number of characters per
line, and pass that value in the CX register.