Specifications

200 AMD Geode™ GeodeROM Functional Specification
Video BIOS Support
32087C
Returns:
13.2.9 Function 08h: VBE Set/Get RAMDAC Palette Format
These subfunctions either change the number of bits per primary (Set RAMDAC Format) or return the current number of
bits per primary (Get RAMDAC Format). Note that some hardware is only capable of 6 bits per gun, also note that for strict
VGA compatibility, the standard modes (modes 00h through 13h) usually only operate with a RAMDAC width of 6 bits per
gun.
On a mode set, the BIOS always sets the mode to 6 bits per gun. If this function is called in a YUV or in a direct color (16-
bit or 24-bit) mode, then this function will fail and AH will be set to 03h on exit.
13.2.9.1 Subfunction 00h: Set Format
Passed:
Returns:
13.2.9.2 Subfunction 01h: Get Format
Passed:
Returns:
Parameter Description
AX VBE return status
Parameter Description
AH 4Fh
AL 08h
BH Desired bits per gun
BL 00h
Parameter Description
AX VBE return status
Parameter Description
AH 4Fh
AL 08h
BL 01h
Parameter Description
AX VBE return status
BH Current number of bits per gun