INT 10 - VIDEO - ALTERNATE FUNCTION SELECT (PSIBM PS/2, any model, VGAVideo Graphics Array(Video Graphics Array) The video adapter introduced with the IBMInternational Busiuness Machines PS/2IBM PS/2, any model series of computers.) - VIDEO REFRESH CONTROL AH = 12h BL = 36h AL = new state 00h enable refresh 01h disable refresh Return: AL = 12h if function supported Desc: specify whether the contents of video memory should be displayed on the screen; disabling refresh effectively blanks the screen Note: when display refresh is disabled, the entire screen displays the color specified by the DAC(Digital-to-Analog Converter) A hardware device (in its simplest form, nothing more than a set of interconnected resistors) which converts a digital number into an analog signal whose voltage is proportional to the value of the digital number. VGAVideo Graphics Array and later color video boards use DACs to convert color values into the analog signals sent to the display; sound boards normally use DACs as well. color register 00h; thus to actually blank the screen, the application must first ensure that that register has been set to black BUG: GEM/VIEWMAX ET3000 and ET4000 drivers dated 1988/6/23 do not correctly reenable refresh after the screen has been blanked due to inactivity, resulting in a total loss of video synchronization SeeAlso: AX=BF05h