讯号协议|VGAtiming information FPGA|相关|Xilinx

VGAtiming information
Thisdocuments tries to collect together information about standard VGA card timingdetails.
Informationform HP monitor manual Horizonal Timing

Horizonal Dots640640640

Vertical Scan Lines350400480

Horiz. Sync PolarityPOSNEGNEG

A (us)31.7731.7731.77Scanline time

B (us)3.773.773.77Sync pulse lenght

C (us)1.891.891.89Back porch

D (us)25.1725.1725.17Active video time

E (us)0.940.940.94Front porch

______________________________

________|VIDEO|________| VIDEO (next line)

|-C-|----------D-----------|-E-|

___________________________________________

|_||_|

|B|

|---------------A----------------|

Vertical Timing

Horizonal Dots640640640

Vertical Scan Lines350400480

Vert. Sync PolarityNEGPOSNEG

Vertical Frequency70Hz70Hz60Hz

O (ms)14.2714.2716.68Total frame time

P (ms)0.060.060.06Sync length

Q (ms)1.881.081.02Back porch

R (ms)11.1312.7215.25Active video time

S (ms)1.20.410.35Front porch

______________________________

________|VIDEO|________|VIDEO (next frame)

|-Q-|----------R-----------|-S-|

___________________________________________

|_||_|

|P|

|---------------O----------------|

Informations source

HP D1194A Super VGA Display & HP D1195A Erognomic Super VGA Display Installation Guide, Hewlett Packard

"VGAindustry standard" 640x480 pixel mode General characteristics

Clock frequency 25.175 MHz

Linefrequency 31469 Hz

Field frequency 59.94 Hz

One line

8 pixels front porch

96 pixels horizontal sync

40 pixels back porch

8 pixels left border

640 pixels video

8 pixels right border

---

800 pixels total per line

One field

2 lines front porch

2 lines vertical sync

25 lines back porch

8 lines top border

480 lines video

8 lines bottom border

---

525 lines total per field

Other details

Sync polarity: H negative, V negative

Scan type: non interlaced.

Information source

Article "Re: VGA specifications ,where ?" posted 19 Nov 1997 to sci.electronics.design newsgroup by Jeroen Stessen

More VGAmode information Thereare the 3 "standard" VGA modes that each VGA card is supposed to beable to do:

640 x 350 x 70 is compatible with the old EGA mode, but on a VGA display.
640 x 400 x 70 is the MS-DOS text mode (when the computer is booting !).
640 x 480 x 60 is the default Windows(tm) graphics mode (16 colours !).

Theirline frequency is exactly twice that of the NTSC television system, or almosttwice that of the PAL television system. This makes it fairly easy to implementa VGA input on a television set that uses line doubling for the televisionsignals so the line deflection already runs on 31 kHz.
Thefollowing timings come from a list of 82 different computer timings, and by nowthere will be even more. Some video cards even have variable timing (allowingthe user to set width, height and shift...). The only standard is that thereis no standard !

"640 x 350 (EGA on VGA)""640 x 400 VGA text""VGA industry standard"

Clock frequency 25.175 MHzClock frequency 25.175 MHzClock frequency 25.175 MHz

Linefrequency 31469 HzLinefrequency 31469 HzLinefrequency 31469 Hz

Field frequency 70.086 HzField frequency 70.086 HzField frequency 59.94 Hz

One line:One line:One line:

8 pixels front porch8 pixels front porch8 pixels front porch

96 pixels horizontal sync96 pixels horizontal sync96 pixels horizontal sync

40 pixels back porch40 pixels back porch40 pixels back porch

8 pixels left border8 pixels left border8 pixels left border

640 pixels video640 pixels video640 pixels video

8 pixels right border8 pixels right border8 pixels right border

---------

800 pixels total per line800 pixels total per line800 pixels total per line

One field:One field:One field:

31 lines front porch5 lines front porch2 lines front porch

2 lines vertical sync2 lines vertical sync2 lines vertical sync

54 lines back porch28 lines back porch25 lines back porch

6 lines top border7 lines top border8 lines top border

350 lines video400 lines video480 lines video

6 lines bottom border7 lines bottom border8 lines bottom border

---------

449 lines total per field449 lines total per field525 lines total

per field

Sync polarity: H positive,Sync polarity: H negative,Sync polarity: H negative,

V negativeV positiveV negative

Scan type: non interlaced.Scan type: non interlaced.Scan type: non interlaced.

Information source
Jeroen H. Stessen kindlymailed this information for me to be added to this document at November 1997.
SuperVGAtiming from NEC monitor manual

Horizontal :

___________________________

|||

_______________|VIDEO|_______________|VIDEO (next line)

______________________________________________________

|_||_|

B C <------D-----><-E->

<----------A---------->

Vertical :

___________________________

|||

_______________|VIDEO|_______________|VIDEO (next frame)

______________________________________________________

|_||_|

P Q <------R-----><-S->

<----------O---------->

For VESA 800*600 @ 60Hz:

Fh (kHz) :37.88

A(us):26.4

B(us):3.2

C(us):2.2

D(us):20.0

E(us):1.0

Fv (Hz):60.32

O(ms):16.579

P(ms):0.106

Q(ms):0.607

R(ms):15.84

S(ms):0.026

【讯号协议|VGAtiming information】Information source

NEC Multisync manual

Necessarytiming information about VGA modes Vertical timinginformation

Mode nameLineslinesyncbackactivefrontwhole frame

Totalwidthpulseporchtimeporchperiod

(us)(us)(lin) (us)(lin)(us)(lin)(us)(lin)(us)(lin)

VGA 640x480 60Hz52531.786329533015382484285916683525

VGA 640x480 72Hz52026.417936862612782484184713735520

VGA 720x400 70Hz44931.78632101632128394043491114268449

VGA 720x350 70Hz44931.786321811571125035411443614268449

VGA 800x600 56Hz62528.445615682017177604-1*17775625

VGA 800x600 60Hz62826.4010645542115945604-1*16579628

VGA 800x600 72Hz66620.80125643621125636047283513853666

IBM 640x480 75Hz52525.3975127613012292484228913333525

MAC 640x480 66Hz52528.578631057371382748428114999525

Notes:

Active area is actually an active area added with 4 overscan border lines (in some other VGA timing tables those border lines are included in back and front porch)
Note than when the active part of VGA page is widened, it passes by the rising edge of the vertical sync signal in some modes (marked with *)

Horizonal timing information

Mode namePixelsyncbackactivefront whole line

clockpulseporchtimeporchperiod

(MHz)(us)(pix)(pix)(pix)(pix)(pix)

VGA 640x480 60Hz25.1753.81964564613800

VGA 640x480 72Hz31.51.274012564621832

VGA 720x400 70Hz28.3223.811085172615900

VGA 720x350 70Hz28.3223.811085172615900

VGA 800x600 56Hz36272125806211024

VGA 800x600 60Hz403.212885806371056

VGA 800x600 72Hz502.412061806531040

IBM 640x480 75Hz31.53.05964564613800

MAC 640x480 66Hz30.242.11649364661864

Notes:

Active area is actually an active area added with 6 overscan border pixels (in some other VGA timing tables those border pixels are included in back and front porch)

Information source