Editing VESA BIOS Extensions (section)

==Standards==

===Early VBE ===
VBE 1.0 (VS891001) was defined in 1989.<ref>{{Cite web |date=2013-12-11 |title=SUPER VGA BIOS EXTENSION Standard # VS891001 › Gemixtes |url=http://www.gemixtes.de/super-vga-bios-extension-standard-vs891001/ |access-date=2022-12-27 |archive-url=https://web.archive.org/web/20131211151957/http://www.gemixtes.de/super-vga-bios-extension-standard-vs891001/ |archive-date=11 December 2013 }}</ref> VBE 1.1 (VS900602) was defined in 1990. VBE 1.2 (VS911022) was defined in 1991.<ref>{{Cite web |date=October 22, 1991 |title=VBE Version 1.2 |url=http://docs.ruudkoot.nl/vesasp12.txt |access-date=2022-12-27 |archive-url=https://web.archive.org/web/20090114055246/http://docs.ruudkoot.nl/vesasp12.txt |archive-date=14 January 2009 }}</ref> These versions of VBE require real mode to work.

VBE defines several new functions called through [[INT 10H]]. The function numbering start with AX=4F00, or (AH=4F, AL=00), for ''Function 00h''. 00h to 05h were defined in VBE 1.0, 06h and 07h in 1.1, and 08h in 1.2.

===VESA BIOS Extensions (VBE core) 2.0 (November 1994)===
This standard provides the primary functionality of the VESA BIOS Extensions. It allows applications to determine the capabilities of the [[graphics card]] and provides the ability to set the display modes that are found. VBE 2.0 adds some new features above the prior VBE 1.2 standard including linear [[framebuffer]] access and [[protected mode]] banking. Some of the VBE Core 2.0<ref>{{Cite web |date=2008-12-11 |title=VBE/Core 2.0 Standard |url=http://docs.ruudkoot.nl/vbe20.txt |access-date=2022-12-27 |archive-url=https://web.archive.org/web/20081211174813/http://docs.ruudkoot.nl/vbe20.txt |archive-date=11 December 2008 }}</ref> features include:

; Linear framebuffer access:  Enables direct framebuffer access in protected mode as one large area of memory instead of less efficient smaller chunks.
; Protected mode banking: Allows access to the framebuffer from protected mode without "thunking" down to [[real mode]]. This is implemented using a new ''Function 0Ah''.
; [[Super VGA]] page flipping: Allows higher performance animation to provide for smooth animation for computer games and other high performance graphics programs.
; Super VGA virtual screens: Allows software to set up virtual [[display resolution]]s, larger than the actual displayed resolution, and smoothly scroll or pan around the larger image.
; [[High Color]] and [[24-bit color|TrueColor]] modes: Industry standard 16-bit and 24-bit graphics modes for resolutions from 320×200 up to {{val|1600}}×{{val|1200}}.

===VESA BIOS Extensions (VBE core) 3.0 (September 1998)===
A superset of the VBE 2.0 standard. This standard adds [[refresh rate]] control, facilities for [[Stereoscopy|stereo glasses]], improved multi-buffering and other functions to the VBE 2.0 standard.

; [[Triple buffering]]:  Allows high speed applications to perform multi-buffering with less screen flickering and without having to wait for the graphics controller.
; Refresh rate control using GTF timings:  This allows applications and operating system utilities to change the refresh rate in a standard way on all VBE 3.0 graphics controllers. Important for stereo applications, since when stereo is enabled, the user's effective refresh rate is cut in half.
; Stereo page flipping:  When viewing an application using stereo [[LCD shutter glasses|glasses]], software needs to page flip twice as often as normal, because it needs to generate separate images for each eye. This new feature allows stereo compatible software to display properly.
; Hardware stereo sync:  Allows stereo software to determine if there is a connector for stereo glasses on the user's graphics card.

A new "Protected Mode Entry Point" was added as an alternative to ''Function 0Ah''.

===VBE/accelerator functions (VBE/AF) (August 1996)===
VBE/AF provides a low-level, standard interface to common acceleration functions available on most hardware. Some of the functions defined in the standard are access to hardware cursors, [[Bit blit|Bit Block Transfers]] (Bit Blt), off screen [[Sprite (computer graphics)|sprites]], hardware panning, drawing and other functions. It is defined to work under 32-bit protected mode.  Despite the widespread adoption of VBE Core, very few devices support VBE/AF.  The [https://shawnhargreaves.com/freebe/ FreeBE/AF] project implements [[Free software|free]] third-party VBE/AF drivers for certain graphics cards.

===Supplemental specifications===
Supplemental specifications provides device independent interface between application software and Super VGA hardware.  Function numbers are assigned by VESA Software Standards Committee (SSC).

====Power management extensions (PM)====
{{further|VESA Display Power Management Signaling}}
DPMS is a hardware standard that allows graphics cards to communicate with DPMS-compliant [[Computer display|monitor]]s via a special signalling system that can be used with existing graphics controllers and monitor cables. This signalling system allows the graphics card to tell the monitor to go into a number of different power management or power saving states, which effectively allow the monitor to turn itself off when it is not in use.

====Flat panel interface extensions (FP)====
Allows access to special features in flat panel controllers.

====Audio interface extensions (AI)====
Provides standard to audio services.

Currently (version 1.00), the VBE/AI specification defines three device classes: WAVE, MIDI, and VOLUME. Device types not covered:

; CDROM control: which is covered by the [[Microsoft CD-ROM Extensions|Microsoft's CD-ROM Extensions]].
; Effects processors: This class of device will be expanded in future version of the VBE/AI specification.

====OEM extensions====
Provides standard entry to vendor-specific extensions.

====Display Data Channel (DDC)====
{{Main article|Display Data Channel}}
The '''Display Data Channel''' or '''DDC''' is a digital connection between a [[computer display]] and a [[graphics card|graphics adapter]] that allows the display to communicate its specifications to the adapter. The standard was created by [[VESA]].

====Serial Control Interface (SCI)====
Provides hardware independent means for operating system and application to read and write data over [[I²C]] serial control interface.