Chinaunix首页 | 论坛 | 博客
  • 博客访问: 2915751
  • 博文数量: 241
  • 博客积分: 15936
  • 博客等级: 上将
  • 技术积分: 25158
  • 用 户 组: 普通用户
  • 注册时间: 2007-03-27 11:22
  • 认证徽章:
个人简介

Fedora-ARM

文章分类
文章存档

2016年(3)

2014年(1)

2013年(3)

2012年(50)

2011年(61)

2010年(26)

2009年(27)

2008年(21)

2007年(49)

分类: Delphi

2012-03-28 14:23:58

在研究VGA视频标准的时候看到的,总结的不错,原文地址:http://www.hardwarebook.info/VGA_(VESA_DDC)
怕以后无法查阅,备份转载如下:
VGA (VESA DDC)

VGA=Video Graphics Adapter or Video Graphics Array
VESA=Video Electronics Standards Association
DDC=Display Data Channel

Contents
Pinout

Videotype: Analogue.


15 PIN HIGHDENSITY D-SUB FEMALE at the videocard.

15 PIN HIGHDENSITY D-SUB MALE at the monitor cable.


PinNameDirDescriptionImpedance/Level
1REDArrowr.pngRed Video75 Ω, 0.7 V p-p
2GREENArrowr.pngGreen Video75 Ω, 0.7 V p-p
3BLUEArrowr.pngBlue Video75 Ω, 0.7 V p-p
4RES-Reserved
5GNDArrow.pngGround
6RGNDArrow.pngRed Ground
7GGNDArrow.pngGreen Ground
8BGNDArrow.pngBlue Ground
9+5VArrowr.png+5 VDC
10SGNDArrow.pngSync Ground
11ID0Arrowl.pngMonitor ID Bit 0 (optional)
12SDAArrowlr.pngDDC Serial Data Line
13HSYNC or CSYNCArrowr.pngHorizontal Sync (or Composite Sync)
14VSYNCArrowr.pngVertical Sync
15SCLArrowlr.pngDDC Data Clock Line

Note: Direction is Computer relative Monitor.

VESA DPMS power saving

DPMS = Device Power Management Signalling

SignalPower save mode
NormalStandbySupspendedOff
13 HSYNCOnOffOnOff
14 VSYNCOnOnOffOff
Power level100%80%<30W<8W
DDC

DDC = Display Data Channel

NamePinsProtocol
SDASCL
DDC11214Unidirection protocol (uses VSYNC (14) as clock)
DDC2B15I2C
DDC2B+I2C (Bidirectional)
DDC2ABI2C (ACCESS.bus)
DDC/CII2C

Note: DDC2 was never implemented

DDC1

DDC1 is a quite simple protocol. Unidirectional communication from the monitor to the video card. VSYNC (14) is used as clock.

DDC2B

Based on Philips I2C protocol. Video card is the master and monitor is always slave. Monitor has address 0xA0 (for write mode) and 0xA1 (for read mode). Control of display is not possible only exchange of information.

DDC2B+

Modification to allow bidirectional communication, point to point. Both video card and monitor can be master and slave. Control of display is possible.

DDC2AB/DDC2B+

Monitors that implement DDC2AB/DDC2B+ are full featured ACCESS.bus devices. Multiple devices on one bus. ACCESS.bus is based on Philips I2C protocol. Default address for monitor is 0x6e and 0x50 for video card (host). Extra information is transmitted thru VDIF (VESA Video Display Information Format).

DDC/CI (formerly DDC2Bi)

DDC/CI = Display Data Channel Command Interface E-DDC (VESA Enhanced Extended Display Data Channel Standard) is the physical standard.

Extended Display Identification Data

EDID = Extended Display Identification Data

EDID 1.0/1.1

The EDID information consists of 128 bytes of monitor data.

Additional blocks of 128 bytes can be stored in EDID extension blocks (aka VDIF) after the initial EDID block. These blocks contain addtional detailed timing information. There is a flag within the EDID to indicate the existence of these blocks. VDIF is not currently used in our systems.

VersionRevisionYearStandard
101994DDC
111996EDID Standard v2
121997EDID Standard v3
201997EDID Standard v3 (Discouraged for future designs)
131999E-EDID Rel A
OffsetNameDescription
00h-07hHeader00h, FFh, FFh, FFh, FFh, FFh, FFh, 00h
08h-09hVendor/Product IDManufacturer IDprovided by Microsoft
0Ah-0BhProduct IDassigned by manufacturer
0Ch-0FhSerial number
10hManufacturing dateWeek1-54
11hYearYear-1990 (must be >3)
12hEDID verionVersionCurrent version 1
13hRevisionCurrent revision 3
14hBasic Display ParametersVideo Input Definition
  • bit 7: 0=analog, 1=digital
  • if bit 7 is digital:
    • bit 0: 1=DFP 1.x compatible
  • if bit 7 is analog:
    • bit 6-5: video level
      • 00=0.7, 0.3, 01=0.714, 0.286, 10=1, .4 11=0.7, 0
    • bit 4: blank-to-black setup
    • bit 3: separate syncs
    • bit 2: composite sync
    • bit 1: sync on green
    • bit 0: serration vsync
15hWidthin cm, 0 for projectors
16hHeightin cm, 0 for projectors
17hGamma
18hPower Management support
  • bit 7: standby
  • bit 6: suspend
  • bit 5: active-off/low power
  • bit 4-3: display type.
    • 00=monochrome, 01=RGB colour, 10=non RGB multicolour, 11=undefined
  • bit 2: standard colour space (sRGB)
  • bit 1: preferred timing mode
  • bit 0: default GTF supported

Note: Little-endian

E-EDID

E-EDID = Enhanced Extended Display Identification Data Standard Up to 32kB of data.

LinksContributionsSource
阅读(4436) | 评论(1) | 转发(6) |
给主人留下些什么吧!~~

jxyfdlh19872012-12-08 13:57:38

作者对此类型很专业

评论热议
请登录后评论。

登录 注册