INT 10H 12H BL=36H: Enable/Disable Screen Refresh
Expects: AH 12H
AL setting: 00H enable refresh
01H disable refresh
Returns: AH 12H if a valid value was passed in AL
Info: This modifies bit 5 of the VGA's Sequencer Clocking Mode Register
(see VGA I/O Ports).
You can draw complex graphics faster while refresh is disabled
(it avoids some enforced wait states). Be sure to re-enable
refresh when finished updating video memory.
See Also: INT 10H 12H (EGA/VGA Special Functions/Alternate Select)
INT 10H: Video Services
EGA/VGA Data Areas