
                      XFree86 Video Timings HOWTO İ
                                       
: Eric S. Raymond <esr@thyrsus.com>
: Ѹ <pxun@163.net>

   v3.6, 13 June 1999 : 1999118
     _________________________________________________________________
   
   Ϊʾ/ʾϱдXFree86µģʽ.XFree86ķ
   а汾ڰ˺ܺõĹ,ȷô׼;ҪΪ
   ĸʾǳӲֹģʽ.Ҳ԰
   kvideogenģʽ,xvidtune޸Ĳ̫ʺʾĳֱ׼
   ģʽ.
     _________________________________________________________________
   
1. 

2. 

3. Զ㹤

4. ʾ

5. ʾʾҪ˽Ļ

     * 5.1 ʾͬƵ
     * 5.2 ʾƵ
     * 5.3 ʾʱ
     * 5.4 Щͳݿʲô
       
6. ԻĽ

     * 6.1 Ƶ
     * 6.2 ͬƵʺˢ:
       
7. ϵͳʱȨ

8. 洢

9. ֡ĴС

10. ͬ

     * 10.1 ͬ
     * 10.2 ͬ
       
11. 

12. ʾ

13. ʹøģʽ

14. 

15. .

     * 15.1 λ
     * 15.2 ϻλ
     * 15.3 ˮƽʹֱ̫
     * 15.4 ˮƽ̫(̫խ)
     * 15.5 ڴֱ̫(̫ǳ)
       
16. ʾ

17. л
     _________________________________________________________________
   
1. 

   ʹĲ,ге.ʾ̼ʱ,
   ͬʱ˺ʾԼ.Ķ [1]ʾȡϸ
   Ϣ.ڹʾɶʾ.
   
   ĵ°汾 [2]Linuxĵƻҳҵ.
   
   ֱӰ,͸Ľ鷢 [3]esr@snark.thyrsus.com.벻Ҫ
   ʼһܽʾķ,ֻľҵ
   ʱ䲢ʧ --- ֪ȫѾ.
   
   ע:κϵĴ,֪ͨ [4]pxun@163.net.߶
   ԭɵκʧһŲκ.
   
2. 

   XFree86ûǵʾϵͳ,ŻʹеӲ
   .ָͼѧԼʱֵŻʹʾ
   ʾ.
   
   ǽһʹϵͳתķ,Ȼչʾɻÿʼ,
   ֱζ.
   
   ѾһֻԹģʽ(ر,ĳԤVESAģʽ
   ȶʾ,һģʽһλ,߻̫С̫)ֱ
   Ķһ [5].޸ʱֵԴﵽЧ.
   
   װһνXʱʾ,ҪٶҪеģʽýе
   ;Ҳ󲿷ģʽгʼȷ,ֻĬֵĳһʺӲ
   .Ӧð'CTRL'-'ALT'-'С+'Ѿװģʽѭл.
   һЩģʽ,Գ640x480һע͵ģʽ,
   ģʽǷ.,ôȥģʽеעͷ,һ800x600
   һ1024x768,趨ΪһʾӦܴƵ.
   
3. Զ㹤

   XFree86 3.2ʼ,XFree86ṩһXF86Setup(1),ܼܺ򵥵ؽʽ
   һֿԹʾģʽ,òֱӶԸ鷳ʾʱֵ.ڴ
   㲻Ҫһֻʾģʽ.ҵ,XF86Setup(1)һЩ;
   ֻʶߵ1280x1024ı׼ʾģʽ.һ̨ǳܵʾ,
   ֧1600x1200,ԲòмĻʾģʽ.
   
   һKDEĹ߽ [6]KVideoGen,ܴӻʾʾͳݱм
   ģʽ.ģʽ,û.ע
   Horizontal Refresh Rate(ˮƽˢ)Vertical Refresh Rate(ֱˢ
   )HSF(Ƶ)VSF(Ƶ)ͬ.Horizontal
   Sync Pulse(ͬ)ֵָԺһͬĿ,ù߼ٶ
   HGT1½HGT2̶ֵ.㲻ֵ֪ͬ,ʹȱʡֵ
   ϰȫ.
   
   汾XFree86ṩһ߽xvidtune(1).ܷܿڲԺ͵
   ʾģʽʱ൱.ʼһηĹڲȷʹÿܵ½
   ľ.ϸоĲѧϰxvidtuneԻƯֺ
   ,㽫Чسĵʹxvidtune.
   
   xvidtune(1),ܿٵزµģʽ,޸Xļ,
   X.,XFree86XconfigĲͬģʽ֮
   л(XFree.manϸ).ʹԽʡĴ!
   Ҫһģʽʱ,һΨһģʽǲӵȼ嵥Ľ
   β.һ֪ģʽΪĬֵ,Եģʽʱ˻ȥ.
   
   ڽӽĽβĵط,ǰһ'modeplot'ű(script),
   ֿѡģʽģͼ.ֱӰģʽ,԰õ
   ֮Ĺϵ.
   
4. ʾ

   ˽ʾXconfigļͬӦʲôֵǲȱ
   .ЩֵXFree86ڶʾײ.
   
   ʾһصһ.Щشγ.Щд
   ϵγɻ.ʾڲĵЩصϾͷ˹.
   Ϊʹȵʱÿ,һֺ㶨ģʽĻ
   ɨ.
   
   ɨĻϽ,Ļֱ,ʱͣĻ
   .ȻĻ,һ.µһһһɨ
   .ģʽϵظֱʾһɨ.ʱʾ
   ƵϽ,ùٴοʼ.
   
   ģʽһֽиɨ:ڵһ֡ÿеһбɨ,
   ڵڶ֡űɨ.
   
   ʾϽǿʼɨһ֡Ŀʼ.ʾ½ٴ
   Ͻʱһ֡ͽ.һ֡ɵʾϴϵɨ
   ейɵ.
   
   ɨ֡ʱǿ,ʾеضᱻ.Ļ
   ԵͲкɫ߿.ĻıԵͻ,Ϊѿ.Ϊ
   ˼ٱ,ʹָĻԵ,Ҳᱻ.
   ,ʾĿͼ.
   
   һҪҪ,ûرɨʱʲô.
   ʾұԵʱڰѵұԵƻԵƵ
   һ.ʾ±Եʱڰѵʾ½ƻ
   Ͻ.
   
   ʾź,ʹʾÿϲ.ͨһ
   Žͬ,ʾҲʲôʱʾѵұƻ߲һ
   .ÿһнʱһͬ.ʾһ֪ͬͨʾ
   ѵƵĻϽ.ڽӽÿһ֡ʱһͬ.
   
   ͬͳ֮ͬǰ֮,ʾҪһζ̵ʱõλ
   ȶ.ȶ,Ҳȶ.
   
   һ,ǽö,ʽͷЩԭ԰ʹ.
   
5. ʾʾҪ˽Ļ

   ޸һXconfigĿǰ,һЩҪ˽.:
   
     * ʾƵͳƵѡ
     * ʾƵ
     * ʾʱƵ,"ʱ"
       
5.1 ʾͬƵ

   Ƶÿʾˮƽɨ;ǹʾһҪͳ
   ֵ.Ƶÿʾֱܴɨ֡.
   
   ͬƵͨʾֲļҳ.Ƶֵ͵Hz(ÿ)
   ,ƵKHz(ÿǧ)궨. ͨƵķΧ50150Hz֮,Ƶ31
   135KHz֮.
   
   һ̨Ƶͬʾ,һƵʷΧ.ĳЩʾ,ǵ͵,
   ж̶Ƶ.Ҳܽ,Ŀѡᱻʾ̶ļ
   ϸ.ΪѵķֱѡߵƵ.ҪС --- ͼһ̶̨
   ƵʾøƼƵʻ׵.
   
   ָϵڰ汾ڹƵͬʾ൱,ʹǳ
   ϵ߳ƵԻøõ.Ժָ˸ɶи
   ;ǽ½ [7]ʾۼ.
   
5.2 ʾƵ

   ʾƵӦðֲļҳ.û,ʾ߶
   ֱ.Ϊһ鷨,ָתΪƵĹֵ(ӶתΪ
   ʹõʱӵĴ):
   
        640x480                 25
        800x600                 36
        1024x768                65
        1024x768          45
        1280x1024               110
        1600x1200               185

   ˳˵һ,ű񲢲;Щֵֻڱ׼XFree86ģʽݿÿֱַ
   ʵʱӶ(һ,òֵϵ).ʵʾ
   Ƶܸܿ߷ֱҪСֵ,ԲҪȥһ
   MHzʱ.
   
   ҲעԼ65MHzµʱ˵,ƵһӰ.һ
   SVGAʾʹ߷ֱʾ,ôҲﵽʾƵ
   ֵ.и:
   
        ͺ                          Ƶ
        ----------                      ---------------
        NEC 4D                          75MHz
        Nano 907a                       50MHz
        Nano 9080i                      60MHz
        Mitsubishi HL6615               110MHz
        Mitsubishi Diamond Scan         100MHz
        IDEK MF-5117                    65MHz
        IOCOMM Thinksync-17 CM-7126     136MHz
        HP D1188A                       100MHz
        Philips SC-17AS                 110MHz
        Swan SW617                      85MHz
        Viewsonic 21PS                  185MHz
        PanaSync/Pro P21                220MHz

   ͵ʾͨֱҲ̫Ƶ.NEC Multisync IIһ
   ܺõ --- ļʾ800x600.ֻ
   ʾ800x560.ĵͷֱ㲻ҪߵʱӻƵ;
   õ32MHz36MHz,ʾĶƵ30MHzԲ̫Զ.
   
   Ƶ,ĻҲûӦﵽô,
   ȻԽ.NEC Multisync IIƵܸ36MHzȻ.ͨ
   ı༭ⲻǺܹؼ,ֻҪҪػμ(
   ۾̸).
   
5.3 ʾʱ

   ʾֲļҳͨÿʱ(ָÿ
   ʾдĻϵܸ).
   
   ֲûϢ,XΪ.汾Xȫ֧
   --probeonly ѡ,ʾϢȻ˳,òXıʾģ
   ʽ.
   
   Xû --probeonly ѡҲҪ.ʹXסʾ,Ի
   һйʱӺϢʾڱ׼.Ϣضһ
   ļ,ᱣ,ʹ㲻òԻص̨.
   
   ̽ĽϢȥӦ֮һ:
   
   ʹXFree86: (ע:ΪĻ,----ΪĻķ˵)
   
Xconfig: /usr/X11R6/lib/X11/Xconfig
         --------------------------
            Xļ·

(**) stands for supplied, (--) stands for probed/default values
                --------                  ---------------------
            (**)ṩֵ                (--)ֵ/ȱʡֵ

(**) Mouse: type: MouseMan, device: /dev/ttyS1, baudrate: 9600
                  --------          ----------            ----
                          豸ļ      봮ͨѶ

Warning: The directory "/usr/andrew/X11fonts" does not exist.
         Entry deleted from font path.
(**) FontPath set to "/usr/lib/X11/fonts/misc/,/usr/lib/X11/fonts/75dpi/"
                      --------------------------------------------------
                                     ·

(--) S3: card type: 386/486 localbus
                    ----------------
                     ʾ

(--) S3: chipset:   924
                    ---
    Chipset(оƬ) --- ȷеоƬͺ;һ86C911֮ǰͺ

(--) S3: chipset driver: s3_generic
                         ----------
                       оƬ

(--) S3: videoram:  1024k
                    -----
         ʾ֡ڴ(׳Դ)ĴС

(**) S3: clocks:  25.00  28.00  40.00   3.00  50.00  77.00  36.00  45.00
(**) S3: clocks:   0.00   0.00  79.00  31.00  94.00  65.00  75.00  71.00
                  ------------------------------------------------------
                              MHzĿõƵ

(--) S3: Maximum allowed dot-clock: 110MHz
                                    ------
                                     Ƶ

(**) S3: Mode "1024x768": mode clock =  79.000, clock used =  79.000
                                        ------                ------
                                            1024x768ģʽʱ

(--) S3: Virtual resolution set to 1024x768
                                   --------
                                Ļֱ

(--) S3: Using a banksize of 64k, line width of 1024
(--) S3: Pixmap cache:
(--) S3: Using 2 128-pixel 4 64-pixel and 8 32-pixel slots
(--) S3: Using 8 pages of 768x255 for font caching

   ʹSGCSX/Inside X:
   
WGA: 86C911 (mem: 1024k clocks: 25 28 40 3 50 77 36 45 0 0 79 31 94 65 75 71)
---  ------       -----         --------------------------------------------
 |     |            |                 MHzĿƵ
 |     |            +--ʾ֡ڴĴС
 |     +--оƬͺ
 +--X

   ע:Ļж¸ɺ(ܵĻ)Žм.ΪXһӦó,
   ʱѭ̻ͻ,ֵ׼ȷ.⼸ι۲ֵǷ
   ȶ;ȶ,صһЩֱֵȶ.ػ,еĻ,
   ʧ(ػ̶Linuxûgpm,SVr4û
   mousemgr).
   
   Ϊ˱ʱӼĲ׼ȷ,ӦдʱֵΪʱֵŵ
   Xconfig --- ʱѭ,XһݿԳԵʱֵ׼ȷ嵥.ʹ
   ӵ:
   
wga
        Clocks  25 28 40 3 50 77 36 45 0 0 79 31 94 65 75 71

   ڸɸ߶ȱ仯ϵͳ,Ҳ԰صXʧ.пX
   ʱ,ϵͳɶôʱֵ,ǲݿҵһƥ
   ʱ --- ҵһ!
   
5.4 Щͳݿʲô

   ʾͬƵʷΧ,ʾʱһ,õļ
   ֱ.ӲǱõʲô̶.һ׳ڵӲ
   ȴûͬ豸ǶԽǮһ˷.һ,һ
   ܵӲԽĻ,ܾܵھӲǱ.
   XFree86˼.
   
   ӦðõʱʾƵƥ.Ȼ,кܴԵ --- һ
   ЩʾܳƵֵ30%.ķڳʾĶƵ;
   ϸ.
   
   ˽Ƶʹڸֿܵǵѡ.ӰʾĻ
   (΢Сϸڵ).
   
6. ԻĽ

   һ½ĺ,һЩҪ˽Ķ.һЩ
   .еʱָı.
   
   Ƶ(HSF)
          ÿˮƽɨ().
          
   Ƶ(VSF)
          ÿ봹ֱɨ().ҪҪˢʵ.
          
   ʱ(DCF)
          ʽı,'ʱƵ';ʾľѹƵ ---
          ÿܷ.
          
   Ƶ(VB)
          뵽ʾƵʾԿɱʱƵ.
          ʾĻ,ƵDCFһ,Ƶ
           DCF/2 ʼ.Ȼ,Ϊʾ΢СϸпԽ
          ʾ,㲻ߵʱ̫,ھ͸.
          
   ֡(HFL,VFL)
          ˮƽ֡(HFL)ʾǹɨɼұ߽ڵˮƽһ
          Ҫ.ֱ֡(VFL)ǰɼ±߽ڵ
          ɨ.
          
   Ļˢ(RR)
          ÿĻػĴ(Ҳ"֡").ƵԽԽ,ΪԼ
          ˸.60HzͿ,VESA׼72Hz͸.
          
          ֵ
          
        RR = DCF / (HFL * VFL)

          עĸеĳ˻ʾĿӷֱʲһ,һ΢.
          Ӵϸ.
          
          ͨģʽָƵ(87Hz)ʵǰ֡:Ե͵ʾ
          Ļȥ˸Ƶ,ÿһֻһĴˢ
          .
          
          Ϊ˼ķǰѸɨȫ֡(ˢ),Ҳ
          43.5Hz.ģʽĻҪͬȫ֡ʵģʽ,Բ
          ȫ֡Ϊ֡ʵģʽ.
          
6.1 Ƶ

   ʾϲԸƵΪƵĻȺͿԸı
   ɫ.ƵζԿСϸ.
   
   ʾõźǰֳ.ЩźһʽתΪģ
   ʽ,Բʽʾ.ǿԿɺܶ򵥲϶,ÿһ
   ζһ̶Ƶ,ܶMHzΧ,,20MHz,40MHz,70MHz.
   ʾƵʵָܲʧʾƵߵģź.
   
   ΪǵĿ,ƵҪΪһʹõʱӵĽƽֹ.
   
6.2 ͬƵʺˢ:

   ʾϵÿһˮƽɨֻɨһ֡ȵĿӲ.κʱĻʵ
   ֻһ,㹻ˢ۾Ӱʹ""
   .
   
   һЩʾͼ:
   
     _______________________
    |                       |     Ƶÿ
    |->->->->->->->->->->-> |     ʾĵ
    |                      )|     ͼһ
    |<-----<-----<-----<--- |     Ĵ
    |                       |
    |                       |
    |                       |
    |                       |
    |_______________________|
     _______________________
    |        ^              |     Ƶÿ
    |       ^ |             |     ʾĵ
    |       | v             |     ͼ
    |       ^ |             |     һ
    |       | |             |     
    |       ^ |             |
    |       | v             |
    |       ^ |             |
    |_______|_v_____________|

   סʵʵĹդɨ߿úܽZε;֮,ͬʱϵ
   ƶ.
   
   ֪ʱӺ֡СˢʵĹϵ.ݶ,һ(Hz)ָÿ
   һ.,ˮƽ֡HFLֱ֡VFL,ôĻҪ
    (HFL * VFL) .Ϊݶʾÿ뷢DCF,Ժ
   ȻʾĵǹҲϵɨĻÿ DCF /(HFL *
   VFL) .Ļˢ,ΪָÿĻܱ(Ӷˢ
   )Ĵ!
   
   ,ܰʺҪĳַʽķֱ÷ֹ˸.
   
   Щͼֵ,һͼ:
   
        RR                                      VB
         |   min HSF                     max HSF |
         |    |             R1        R2  |      |
max VSF -+----|------------/----------/---|------+----- max VSF
         |    |:::::::::::/::::::::::/:::::\     |
         |    \::::::::::/::::::::::/:::::::\    |
         |     |::::::::/::::::::::/:::::::::|   |
         |     |:::::::/::::::::::/::::::::::\   |
         |     \::::::/::::::::::/::::::::::::\  |
         |      \::::/::::::::::/::::::::::::::| |
         |       |::/::::::::::/:::::::::::::::| |
         |        \/::::::::::/:::::::::::::::::\|
         |        /\:::::::::/:::::::::::::::::::|
         |       /  \:::::::/::::::::::::::::::::|\
         |      /    |:::::/:::::::::::::::::::::| |
         |     /     \::::/::::::::::::::::::::::| \
min VSF -+----/-------\--/-----------------------|--\--- min VSF
         |   /         \/                        |   \
         +--/----------/\------------------------+----\- DCF
           R1        R2  \                       |     \
                          min HSF                |    max HSF
                                                 VB

   һͨʾģʽͼ.ͼxʾʱ(DCF),yˢ(RR).
   ͼϵʾ:ڵÿһ㶼һֿܵʾģ
   ʽ.
   
   Ϊ'R1''R2'ֱߴһ̶ķֱ(640x480);ǻ
   ͨʱӺˢʵĺܶ಻ͬʵһֱ.R2߱R1˸ߵ
   ֱ.
   
   ±߽ǴƵֵˮƽ.Ƶʱӵ,һ
   ұĴֱߴ.
   
    [8]ʾ)ҵһΪԼʾƵ
   ͼ(Xͼν,ÿ).һ»ȤĲ;Ƶƶɵ
   ߽.
   
7. ϵͳʱȨ

   ķʽĵóĹʽ
   
        DCF = RR * HFL * VFL

   ֮,ʱǹ̶.ܸʱӸˢ,ˮƽֱʻ
   ֱֱ.еһ,һ.
   
   ע,ˢʲܴʾƵ.,κһضʱ
   ضʾ,һ㲻ǿƵڵС֡˻.
   
   ѡʱ,ס:RRõ̫,Ļͻ˸.
   
   㲻ˢΪ60Hz.ӫ˸Ƶ;Դ˱Ƚ,
   ҪߵVESA˻ѧ׼涨72Hz.
   
   ˸ʹ۾ƣ,ʹ۾ӦԶҸ˶кܴĲ
   .90%ӽʾ,ʹúɫͺܺöԱȶɫǰ,͵
   е,45Hz**.
   
   ϸ:xterm -bg white -fg blackһױͺɫǰ
   xterm,ʹ󵽸.ڰʾȵֵ
   3/4,ʾת.һԿʾ(ʹΧ浥Ԫ).
   ûиеκ˸˸̶ǿ̵,ôˢʶ˵.
   һߵˢ,Ϊְӵ˸Ѹʹ۾ƣͲ
   ͷ,ʹĻڳӽǿȥ.
   
   Ըģʽ,˸ڸ,統ǰĴֱֱʺʵ
   Ļ.ֱһ°.㲻ϣԼ85Hz֡ʵ.
   
   ΪѾѡһɽܵˢ.ѡHFLVFLʱ,㽫
   һЩĿռ.
   
8. 洢

   õ֡ڴڲɫҶȼʾܴﵽķֱ.ֻкڰ
   ɫûлҶǳ仯ʾûʲôӰ.
   
   256ɫʾ,ÿӵҪһֽʾڴ.ֽڰ˾
   ɺɵϢ.Ҫ֪ҪԴ,ÿпԿ
   .ʾֱ1024x768, 1024 * 768 = 786,432ʾĿ
   .ÿһֽڵ,ҲʾҪʾڴֽ.
   
   ,ʾڴһ (HR * VR) / 1024 Kֽڲ(
   оȷֵ768K).Դʵ,жԴĻ
   .
   
   Ȼ,ʾֻ512K,ôͲʹø÷ֱ.ʹкõʾ
   ,û㹻ʾڴ,ǲܷʾǱ.һ,SVGA
   ʾ1Դ,ʾʾ800x600,ôҲﲻ߷
   ( [9]ʹøģʽһܵĲȷ).
   
   Դ벻Ҫ;XFree86ͨĻɼ
   ЩԴ(XconfigĵĻСĲ).Ҳסһ512K
   ʾʵʰװԴ治512,000ֽ, 512 * 1024 = 524,288 
   .
   
   һS3ʾX/Inside,16ɫ(ÿ4λ),
   XconfigɫΪ4,Чذʾܴķֱʼӱ.,
   1024x768x256S3ʾ,ʹ4λɫȵ1280x1024x16.
   
9. ֡ĴС

   :ַΪƵͬʾо.Ҳڹ̶Ƶʾ
   ,ûб֤.
   
   ʼʱͨDCFĿߵHSFõһˮƽ֡.
   
   ;һSigma Legend SVGA,ʱ65MHz,ʾƵ
   55KHz.ô(DCF / HSF)õ1181(65MHz = 65000KHz ; 65000 / 55
   = 1181).
   
   ĵһ.ҪΪӽ8ı.SVGA
   S3ʾʹõVGAӲⲽ;ʹһ8λĴ,3
   λ,ʵһ11λ.ʾATI 8514/AҲûҪ
   ,ǲ֪,Σ.԰Ѻõˮƽֵ֡
   Ϊ1176.
   
   (DCF / HSF Ϊ8ı)õСHFL.ͨͬ
   ͵HSFܻøHFL(Ӷ,ĻϿиˮƽ).Ǹ
   ˢʺ͸׾˸.
   
   Ϊһ鷨,ˮƽ֡80%ˮƽɨߵĿӲ --- ˮƽֱ
   (Զ˱Եͺʱ --- ǵĻұԵƵ
   դߵԵҪʱ).ˮƽֱ944.
   
   ,Ҫ4:3Ļ߿,ĴֱֱΪղˮƽֱ
   ʵ3/4.Ӷ708.ҪʵʵVFL,1.05õ743.
   
   4:3ǼϵĹ涨;һͬıõĻʵʳߴ
   ,ȫʹ.4:3ʹӶԽ߳֡ߺ֡úܷ,ֻ
   ҪöԽ߳0.8õ,0.6õ.
   
   , HFL = 1176  VFL = 743 .65MHzߵĳ˻һ
   ,74.4Hzˢ.ü!VESA׼!Xʱõ944x708,Ԥ
   800x600.ȫ!
   
   ܸһظĽˢ,ﵽ76Hz,ΪʾԸڶ
   Լ2KHzƵʽͬ΢VFL(֮,дֱֱС944
   75%).ڳ""Ļ֮ǰ,Ҫ,ȷʾ
   ǹƵܴﵽ76Hz.(,еNEC 4D.VSFֻܴﵽ75Hz).(
   [10]ʾȫ.)
   
   Ϊֹ,ݴ󲿷Ǽ򵥵͹ڹդʾĻʵ.ȫ
   ûκ!
   
10. ͬ

   ,Ϊѡʱ HFL / VFL ,ҳ˿ɽܵˢ,
   㹻ʾڴ. --- Ҫ֪ʲôʱͬ
   .
   
   ͬʵϿʾƵͳƵ.ӼHSFVSF
   ϵ,ƵͬƵֵ.ʾͬźŸʾʵ
   Ƶ.
   
   ͼ?դɨһ֡Ҫʱֻвʾӻ(
   ķֱ).
   
10.1 ͬ

   ֮ͨǰĶ,ˮƽɨһHFL.ǰѿĿ(Ļˮƽ
   )ΪHR.˸ݶȻ HR < HFL .,Ǽͬʱʼ,
   ʾ:
   
  |___ __ __ __ __ __ __ __ __ __ __ __ __
  |_ _ _ _ _ _ _ _ _ _ _ _                |
  |_______________________|_______________|_____
  0                       ^               ^     λ:
                          |   ^       ^   |
                          HR  |       |  HFL
                          |   |<----->|   |
                          |<->|  HSP  |<->|
                          HGT1         HGT2

   ,ʾҪڳHSPλ÷һͬ,Ҳڿ
   صĩ˺֡صĩ֮λ.Ϊʲô?Ϊ
   Ļ,ôĻͲƫ.ĻӦڵĵط,ε
   ʾĿ.
   
   ,ͬÿһǶҪԼ30Ϊ"ʱ".HGT1HGT2
   ʾ.һ͵HGT1HGT2,ڴ㽨һ,Ҫ
   ȿʼ(֮,ͬпʼ).
   
   ͬô֢״ͼĻƫ,һ߹ֵؿ,һͼ
   ĻԵƹ,һɫߺһ"ͼ".һλòʵĳͬ
   ڻʹ˳ͬƵĵӻһ(ʵ,תʱ
   ͬ).
   
   ˵Ļ,ʾͬȻڼĵ.û,
   ʼ...
   
   һ,㽫ò.ʱ,ǿ԰ȫؼٶһͬ
   峤ȴԼ3.54.0΢.
   
   ,ΪHSP3.8΢(˳˵һ,һʼֵ).
   
   ,65MHzʱֵ,֪HSP247(= 65 * 10**6 * 3.8 *
   10^-6) [ǵ M=10^6, micro=10^-6]
   
   һЩϲǵˮƽ֡ؿΪʱ.Ҳῴ
   :
   
   Ծʱ(HAT)
          ൱HR,ԺΪλ. HAT * DCF = HR .
          
   ʱ(HBT)
          ൱(HFL - HR),ԺΪλ. HBT * DCF = (HFL - HR) .
          
   (HFP)
          HGT1.
          
   ͬʱ
          HSP.
          
   ½(HBP)
          HGT2.
          
10.2 ͬ

   صͼ,ͼʾ247?
   
   ǵ,HR944HFL1176.֮ 1176 - 944 = 232 < 247 !Ȼ
   ǲòЩ.ô?
   
   Ȱ1176ߵ1184,944͵936.ڲ 1184 - 936 = 248 .,ӽ
   Щ.
   
   һ,ǲ3.83.5HSP;ô,ǵó 65 * 3.5 = 227 .
   .248227߶.ͨHRSPĿʼ֮ҪԼ30,SPĽ
   HFL֮Ҳһ.Ǳ8ı!Ǳס?
   
   .ô, 936 % 8 = 0 , (936 + 32) % 8 = 0 . 936 + 32 = 968
   , 968 + 227 = 1195 , 1195 + 32 = 1227 ...⿴̫.
   8ı,ǰΪ1232.
   
   Ǳڵ鷳,ͬ岻λhH.ҿüǷ
    1232 - 32 = 1200 Ҳ8ı, (1232 - 32) - 968 = 232 ,Ӧʹ
   3.57΢볤ͬ,Ȼ.
   
   , 936 / 1232   0.7676%,Ȼ80%Զ,Ӧû.
   
   ,ʹõǰˮƽ֡,Ҫʾͬ52.7KHz(= 65MHz / 1232),
   ܷΧ֮.û.
   
   ǰľ鷨, 936 * 75% = 702 ,µĴֱֱ. 702 *
   1.05 = 737 ,µĴֱ֡.
   
   Ļˢ= 65MHz / (737 * 1232) = 71.6Hz .Ȼܺ.
   
   Ƶػͬ岼:
   
   |___ __ __ __ __ __ __ __ __ __ __ __ __
   |_ _ _ _ _ _ _ _ _ _ _ _                |
   |_______________________|_______________|_____
   0                      VR              VFL     λ:
                           ^   ^       ^
                           |   |       |
                           |<->|<----->|
                            VGT    VSP

   ڴֱظսʱʼͬ.VGTͬĴֱʱ.
   ʾVGTΪ0(ûзʱ)ʱû.趨.
   Ҫصķʱ,ͨûк.
   
   ص:֡Ķ,һֱʱǸһˮƽ֡ʱ,
   ǵ, 1232 / 65MHz = 18.95us .
   
   һͬӦ50us300usΧ֮.150usһ
   ,8ֱʱ(150us / 18.95us   8).
   
   һЩϲǵĴֱ֡ؿΪʱ.Ҳῴ
   :
   
   Ծʱ(VAT)
          ൱VR,΢Ϊλ. VAT * VSF = VR .
          
   ʱ(VBT)
          ൱ (VFL - VR) ,΢Ϊλ. VBT * VSF = (VFL - VR) .
          
   (VFP)
          VGT.
          
   ͬʱ
          VSP.
          
   ½(VBP)
          ڳͬһʱ.ͨ.
          
11. 

   XconfigļƵģʽ,ÿһжXĳһģʽӦ
   һļ.ΪĶ,ƶ,ʱƵʶ,ˮƽκʹֱ
   .
   
   ƶΰһ,ǸҪ˵ʾģʽ.Xconfig
   ͼöε"Modes"б.ǰһе뵱ǰһ
   ,Ժ.
   
   ʱӶνʾģʽеʱ(֮ǰDCF).еָ
   ڲиֵʱֵ.
   
   ˮƽĸ,ָʾÿһˮƽ.εĵһÿ
   бγɻ(ǰHR).εĵڶ(SH1)ָͬ
   ĸؿʼ.(SH2)ָͬĸؽ.ĸָ
   ˮƽ֡ܳ(HFL).
   
   ֱҲĸ.һʾϿĿ(VR).ڶ
   (SV1)ָͬпʼ.(SV2)ָͬн.
   ĸֱ֡ܳ(VFL).
   
   :
   
     #ģʽ    ʱ       ˮƽʱ           ֱʱ

     "752x564"     40    752 784  944 1088  564 567 569 611
                   44.5  752 792  976 1240  564 567 570 600

   (ע:ǰX11R5ִ֧Сʱֵ.)
   
   Xconfig,ἰ --- з,ѷͬ
   ʼָ,ʱ,֮ͬ
    --- ÿе.ˮƽܱ8.
   
   ˮƽֵʾ: 800 864 1024 1088
   
   ʾǷ(800),ͬʼλ(864),ͬ
   λ(1024),ˮƽһλ(1088).
   
   ٴע,ˮƽֵ(800,864,1024,1088)Ҫܱ8!ֱֵҪ
   .
   
   ʾϵµ֡.һ֡Ļʱź.˻.
   һʾ֮ͳ֮ͬǰ,еӳ.Ȼͬ
   ,֡ĩβн,Ϊ֮ӳ.ض
   ʾģʽʱҪֵָһƵķʽ.
   
   ֱֵʾ: 600 603 609 630
   
   ָʾ600,ͬ忪ʼڵ603,ڵ609,
   Լܼ630.
   
   עⴹֱֵҪܱ8!
   
   ǻصԭ۵.,ڿʼҪľǰǵĽ
   ʽдXconfig:
   
<>   DCF     HR  SH1 SH2   HFL   VR  SV1 SV2 VFL

   SH1ͬĿʼSH2ǽ;ͬ,SV1ǳͬĿʼ
   SV2ǽ.
   
   ҪЩֵ,һͬ.SH1ͬ
   Ŀʼ;, SH1 = HR + HGT1 .SH2½صĽ;, SH2 = SH1 +
   HSP .ͬ, SV1 = VR + VGT (ֻVGTͨΪ0) SV2 = SV1 + VSP .
   
#     ʱ        ˮƽʱ            ֱʱ     ־
 936x702  65      936 968 1200 1232   702 702 710 737

   Ҫ־;Ϊһģʽ..
   
12. ʾ

   ʾǹ̶Ƶʵ,ԲӦͼԽɨƵ.Ļ
   Ӳ.ҲӦ֪һ̨ƵͬʾܻǱڵĲ׾
   .
   
   ෴,ʱӸʾƵһ޺.(ע:ʱӴﵽ
   ʾƵʱ,Ҳʹﵽ˿ɱۼ.ο˹ض
   [Nyquist's Theorem]һֱӦ:ؿźڿռֲĲ
   ͻΪʲô.)
   
   ˶ͬƵʱ.ĳЩʾҲб·,Σ
   ɨƵʱرʾ,Ҫ.һЩɵĶƵͬʾ(
   Multisync II),ֻʹһˮƽѹ.ʾԹû̫ı
   .иѹڵ·(ڹ̶Ƶʾпû)ͬʱ,Ḳ
   ÿܵƵʷΧ,ڱ˵ͺ.ⲻζ·и,
   ҲʹĻӫ۸ϻ,ʹʾڶֵķ(X).
   
   ƵһҪʾ迹ֻΪ÷ΧƵָ,ʹøߵƵ
   ʻӰ,ĻֲĸźͶߵͨŵĸ.
   
   Ȼ,ʾת(ƵźŵĶͶ),ͨ
   ʵʵƵ,ʾƵ(ʾ̹
   Ļ).
   
   ҪС...
   
13. ʹøģʽ

   (һº̶ܴϹ鹦David Kastrup
   <dak@pool.informatik.rwth-aachen.de>)
   
   ʾͬ·ȶ֧һ̶ʱӵĻ,һ̨ʾ
   ˸Ҫһ̨ʾϲ.ΪȷǸģʽ.
   
   ģʽõΪͬƵVSF(ڹоĲ)ڶ
   Ӧģʽ.ͬƵ¸ģʽԽΪԽ,Ƶͨʾ
   /ʾԵ.
   
   ڹ̶ˢ(֡,VSF),ʾΪ˸:һ̨90Hzĸʾ
   һ̨90Hzʾ.Ȼ,ֻҪһƵһƵ.
   ͬʱӺͬɨºģʽȽ,Խ:45Hz
   ģʽ޷ܵ.90Hzĸģʽ,ҵMultisync 3Dʾ(
   1024x768)Ѿ˼,оǳ.ҲҪ70Hzʾ
   ͬ.
   
   ,ҪעҪ:ֻڸ߷ֱʹøģʽ,ɨ
   Ǳ˴˿.ҲҪͬĿȺλô򽻵Իȶɨ
   λ.ɨǽ,Ļ.һӦóѡ
   һͼΪ˵(XCept,˵Ǿ֪ûӦó
   ).ΪʹXCept,л800x600,ΪĻ˺ҵ۾.
   
   Ϊͬԭ,ʹ100dpi,ˮƽʻΪɨ߿
   (ڸ߷ֱ,嶼û).
   
   Ȼ,Ӳˢ֧ģʽĻͲҪʹøģʽ.
   
   ,㷢ĳЩֱʾʾƵǵ,Եõ
   ˲˸ˮʴ(Ƶ)Ļ,ҲҪֱͬʹ
   øģʽ.ȻʾVSFѾӽ伫Ҳûõ.
   
   øģʽ:ģʽһ.ֻ࿼:ֱ(
   ģʽеһ)Ҫһ,Լָ"Interlace"־ʱ,ʾ
   ʵʴֱ֡ʼӱ.ָģʽ45Hzģʽ"Interlace"־,
   ʾ֧90Hz֡.
   
   һ,1024x768ģʽҵģʽ:ҵMultisync 3Dָ֧
   90HzƵ38KHzƵ.
   
ģʽ "1024x768" 45 1024 1048 1208 1248 768 768 776 807 Interlace

   ڸģʽƶǡػþ.ָͬģʽ,ֻû"Interlace"
   ־,Ȼﵽʾˮƽļ(ϸ˵,΢ڳƵ),
   ޷ܵ˸.
   
   ù:һģʽ,Сʾֱһ,ʹֱΪ
   "Interlace"־.ʾἫĽ.
   
   ʹģʽ,þʾļ(гĳ
   ƵһʾֵԼ30%)ֶһָģʽ(΢Щ
   ķֱ)ϺõЧ,ҲܶԴ˳ŵ.
   
14. 

   :ٵӲǱ׼Ļֱ,ҿ?
   
   :Ϊʲô?ûһʹ640x480,800x600,
   1024x768.XFree86Ӳʱкܴ.ͨγ
   ҳȷ.ҪõҪĶںСĿµĸˢ
   ,˸۾Ϊ۵ĸ߷ֱ!
   
   :65MHzʱӺ55KHz HSFʱΨһķֱ?
   
   :Բ!㱻ѭĲ貢зҳϲ
   .Ȥ.ҲֻǸƵź,
   ʵһ̨ʽƵͬʾͨǲ𻵵.ڳʹһģʽǰ
   ȷʾָ֧ģʽ֡.
   
   СĹ̶Ƶʾ!൱ٵʹ.ȷǽе
   ÿ鶼Чˢ.
   
   :ἰֱ׼ֱ.Xconfig,кܶõı׼ֱ,ܸ
   ޸ʱʱǷʲôҪ?
   
   :!ڵǰXconfigг"׼"ģʽ640x480Ϊ.ʹ25MHz
   Ƶ,֡800525=>ˢԼΪ59.5Hz.̫.ԺܶSVGA忨
   ˵28MHzһͨʹõƵ.640x480,
   ۵Ĳ,ɵõ֡Ϊ812(Ϊ808)505.ˢ68Hz,
   һԱ׼ģʽ൱ĸĽ.
   
   :ܶΪֹ۵ܽ?
   
   :֮:
   
    1. κι̶Ƶ,ֱʻˢʽ͵Ĵ۴Ӷ
       Ե˸.
    2. ø߷ֱʶʾҲ֧,跨һṩƥʱֵ
       DCFSVGA.ԽԽ!
       
15. .

   ,ѾXõֵ.ǷXconfigһģʽıע.
   X,ȼлģʽ,...濴.ô?һ嵥,
   ƵԼνо.
   
   (ЩСıxvidtune(1)֮.)
   
   ͨıͬʱƶ.ͨı֡Ż(ƶ
   ͬԱֻڶӦͬλ,Ҳƶ).һЩ
   ϸķ:
   
   ˮƽʹֱλǶ.֮,ˮƽƶ治Ӱ촹ֱλ,֮Ȼ.
   ,ŶԾͲ̫ȷ.Ȼıˮƽߴ粻ı䴹ֱߴ,֮Ȼ,
   ܵĸıƵ.رĻ̫ʱ,Ų
   һߵʱ.Ϊ˿õķֱ,Ϊ
   һ!
   
15.1 λ

   Ҫ,ƶͬ.֮,Զͬغ½صˮƽʱ
   мֽ(8ı).
   
   ƫ(ұ߽̫,ƶ).ƫ(߽̫
   ,ƶ)ͬ.
   
15.2 ϻλ

   Ҫ,ƶͬ.֮,Զ˳ͬغ½صĴֱʱ
   мֽ.
   
   ƫ(±߽̫,ƶ).ƫ(ϱ߽̫
   ,ƶ).
   
15.3 ˮƽʹֱ̫

   лһߵʾʱٶ.ʱļжģʽ,ܿ
   һģʽؼ.
   
15.4 ˮƽ̫(̫խ)

   Ҫ,()ˮƽ֡.֮,ıһʱεĵĸ.Ϊ˱
   ƶ,Ҳͬ(ڶ͵)ƶһĵ,Աֻڶ
   Ӧͬλ.
   
15.5 ڴֱ̫(̫ǳ)

   Ҫ,()ֱ֡.֮,ıڶʱεĵĸ.Ϊ˱
   ƶ,Ҳͬ(ڶ͵)ƶһĵ,Աֻڶ
   Ӧͬλ.
   
   κβͨЩɵıκܿǷһЩļ
   ,ʱӸʾܴķΧ.
   
   ,סһ֡ήˢ,֮Ȼ.
   
   ʱͨʾĻСı.ȱΪ˾
   ͼģʽ()趨̫ԶĻ,Ҳıģʽ»
   Ź.ĺģʽǸõķ.
   
16. ʾ

   Ҫһʾģʽͼ,㽫Ҫgnuplot(һUNIXϵͳµĻͼ
   )modeplot.һѡʾͼ
   shell/gnuplotű
   
   modeplotһݿ:
   
#!/bin/sh
#
# modeplot--ʾʹõXģʽͼ
#
# ִ'modeplot -?'֪ѡ.
#

# ʾ.ƵMHzΪλ,ƵKHzΪλ,ƵHzΪλ.
TITLE="Viewsonic 21PS"
BANDWIDTH=185
MINHSF=31
MAXHSF=85
MINVSF=50
MAXVSF=160
ASPECT="4/3"
vesa=72.5       # VESAСˢ

while [ "$1" != "" ]
do
        case $1 in
        -t) TITLE="$2"; shift;;
        -b) BANDWIDTH="$2"; shift;;
        -h) MINHSF="$2" MAXHSF="$3"; shift; shift;;
        -v) MINVSF="$2" MAXVSF="$3"; shift; shift;;
        -a) ASPECT="$2"; shift;;
        -g) GNUOPTS="$2"; shift;;
        -?) cat <<EOF
modeplot control switches:

-t "<description>"   name of monitor            defaults to "Viewsonic 21PS"
-b <nn>              bandwidth in MHz           defaults to 185
-h <min> <max>    min & max HSF (KHz)        defaults to 31 85
-v <min> <max>    min & max VSF (Hz)         defaults to 50 160
-a <aspect ratio>    aspect ratio               defaults to 4/3
-g "<options>"       pass options to gnuplot

The -b, -h and -v options are required, -a, -t, -g optional. You can use -g to
pass a device type to gnuplot so that (for example) modeplot's output can be re
directed to a printer. See gnuplot(1) for details.

The modeplot tool was created by Eric S. Raymond <esr@thyrsus.com> based on ana
lysis and scratch code by Martin Lottermoser <Martin.Lottermoser@mch.sni.de>

This is modeplot $Revision: 1.9 $
EOF
                exit;;
        esac
        shift

done

gnuplot $GNUOPTS <<EOF
set title "$TITLE Mode Plot"

# ħֵ.ҵͼǵĸı൱,ĳЩʾǲܴʵ
ֵ.Ҫ
# ЩֵԻøӽģʽͼ.ЩֵǲModeDBݿдֵõ.
F1 = 1.30       # תˮƽֱʵ֡ı
F2 = 1.05       # תֱֱʵ֡ߵı

# (1.0ǿȽʵ)
ac = (1.0*$ASPECT)*F1/F2
refresh(hsync, dcf) = ac * (hsync**2)/(1.0*dcf)
dotclock(hsync, rr) = ac * (hsync**2)/(1.0*rr)
resolution(hv, dcf) = dcf * (10**6)/(hv * F1 * F2)

# Ϸñ
set xlabel 'DCF (MHz)'
set ylabel 'RR (Hz)' 6  # Yұ߷

# ͼ
set grid
set label "VB" at $BANDWIDTH+1, ($MAXVSF + $MINVSF) / 2 left
set arrow from $BANDWIDTH, $MINVSF to $BANDWIDTH, $MAXVSF nohead
set label "max VSF" at 1, $MAXVSF-1.5
set arrow from 0, $MAXVSF to $BANDWIDTH, $MAXVSF nohead
set label "min VSF" at 1, $MINVSF-1.5
set arrow from 0, $MINVSF to $BANDWIDTH, $MINVSF nohead
set label "min HSF" at dotclock($MINHSF, $MAXVSF+17), $MAXVSF + 17 right
set label "max HSF" at dotclock($MAXHSF, $MAXVSF+17), $MAXVSF + 17 right
set label "VESA $vesa" at 1, $vesa-1.5
set arrow from 0, $vesa to $BANDWIDTH, $vesa nohead # style -1
plot [dcf=0:1.1*$BANDWIDTH] [$MINVSF-10:$MAXVSF+20] \
  refresh($MINHSF, dcf) notitle with lines 1, \
  refresh($MAXHSF, dcf) notitle with lines 1, \
  resolution(640*480,   dcf) title "640x480  " with points 2, \
  resolution(800*600,   dcf) title "800x600  " with points 3, \
  resolution(1024*768,  dcf) title "1024x768 " with points 4, \
  resolution(1280*1024, dcf) title "1280x1024" with points 5, \
  resolution(1600*1280, dcf) title "1600x1200" with points 6

pause 9999
EOF

   һ֪modeplotgnuplotѾʵλ,Ҫʾ:
   
     * Ƶ(VB)
     * ƵΧ(HSF)
     * ƵΧ(VSF)
       
   ƳҪһЩȫȷļ򻯼ٶ.˵óͼֻһ
   .Щٶ:
   
    1. зֱеһĹ̶Ļ߿ AR = HR / VR .׼ֱ AR =
       4/3  AR = 5/4 .modeplotĬϼٶ4/3,滻.
    2. Լģʽ,ˮƽʹֱֱ֡ˮƽʹֱֱʵĹ̶:
       
        HFL = F1 * HR
        VFL = F2 * VR

   ΪһݴԵָ, F1 = 1.30  F2 = 1.05 ( [11]frame "֡
   С").
   
   ڴһͬƵ,HSF.ݸղļٶ,ÿֵʱƵ
   DCFѾˢRR,Ҳ˵,HSFÿֵһRR(DCF).
   иó.
   
   ˢʵʱƵʳ֡ĳ˻:
   
        RR = DCF / (HFL * VFL)          (*)

   һ,ˮƽ֡ʱʳƵ:
   
        HFL = DCF / HSF                 (**)

   ٶVFLԻΪHFL:
   
        VFL = F2 * VR
            = F2 * (HR / AR)
            = (F2 / F1) * HFL / AR      (***)

   (**)(***)(*)ǵõ:
   
        RR = DCF / ((F2 / F1) * HFL**2 / AR)
           = (F1 / F2) * AR * DCF * (HSF / DCF)**2
           = (F1 / F2) * AR * HSF**2 / DCF

   ڹ̶HSF,F1,F2AR,ǵͼһ˫.ƵСֵֵ
   Ǿ͵õ߽.
   
   ֱߴضķֱ.ǻ(*)͵ڶٶ:
   
        RR = DCF / (HFL * VFL) = DCF / (F1 * HR * F2 * VR)

   ͨΪĳ˸Ȥзֱʻֱ,̼סʾԷΧڷ
   ,ʱƵʺˢ֮ܵĹϵ.עЩ߲ʾ,ȷ
   ʵڵڶٶ.
   
   modeplotṩ׵;ͼ.modeplot -?Ŀѡ
   .һ͵:
   
        modeplot -t "Swan SW617" -b 85 -v 50 90 -h 31 58

   -bѡָƵ;-v-hƵͳƵΧ.
   
   Ķmodeplotʱ,ʼռסֻƵ.,ͬ
   ȵСҪɵHFL,ľȷٶľȷ.
    [12]гֵϸĴƷ(漰ĳЩ).
   ,ʲôǿܵĺЩȨйص,Ӧøõĸо.
   
17. л

   ԭεChin Fang <fangchin@leland.stanford.edu>.
   
   Eric S. Raymond <esr@snark.thyrsus.com> ŬĻ¼ӹ,
   ֯дChin Fangԭ.,Bob Crosson
   <crosson@cam.nist.gov> дһƪHOWTOĴ󲿷.
   
   ģʽҪDavid Kastrup
   <dak@pool.informatik.rwth-aachen.de>.
   
   Martin Lottermoser <Martin.Lottermoser@mch.sni.de> ʹgnuplot
   ģʽͼ뷨,modeplotѧ.modeplotESR
   MartinԭʼgbuplotΪĵƺ͹ɳ.

References

   1. file://localhost/tmp/zh-sgmltools.10692/XFree86-Video-Timings-HOWTO.txt.html#overd
   2. http://metalab.unc.edu/LDP
   3. mailto:esr@thyrsus.com
   4. mailto:pxun@163.net
   5. file://localhost/tmp/zh-sgmltools.10692/XFree86-Video-Timings-HOWTO.txt.html#fixes
   6. http://without.netpedia.net/kvideogen/
   7. file://localhost/tmp/zh-sgmltools.10692/XFree86-Video-Timings-HOWTO.txt.html#overd
   8. file://localhost/tmp/zh-sgmltools.10692/XFree86-Video-Timings-HOWTO.txt.html#cplot
   9. file://localhost/tmp/zh-sgmltools.10692/XFree86-Video-Timings-HOWTO.txt.html#inter
  10. file://localhost/tmp/zh-sgmltools.10692/XFree86-Video-Timings-HOWTO.txt.html#overd
  11. file://localhost/tmp/zh-sgmltools.10692/XFree86-Video-Timings-HOWTO.txt.html#frame
  12. file://localhost/tmp/zh-sgmltools.10692/XFree86-Video-Timings-HOWTO.txt.html#synth
