Information page about the Intel machines

Sun Monitors

This is configuration information of Sun Monitors.

The old sun monitors, GDM-1662B works at this four modes:

Resolution  1152 x 900    1152 x 900   1076 x 824    944 x 736
Clock        92.94505MHz  105.561MHz   105.561MHz    92.94505MHz
HSynch       61.80kHz      71.71kHz     71.71kHz     70.84kHz
VSynch       65.95 Hz      76.05Hz      76.05Hz      84.03Hz

So, probably the entry for the monitor in XF86Config file looks like
this(although I have not tested yet):  

 Bandwidth     110
 HorizSync     71
 VertRefresh   72

 #             < name >       DCF     HR  SH1  SH2  HFL   VR  SV1 SV2 VFL
 ModeLine      "1152x900"     110    1152 1184 1568 1600  900 903 909 930


 Calculation 
This calculation is based on the document
     "/usr/X11R6/lib/X11/doc/VideoModes.doc". 

Monitor's video bandwidth is, according to the table in the document,

	1152x900	  90MHz

(although there is no description about this resolution, but it must
be proportional to the number of dots in screen.)

	DCF = 90MHz

But, since visible area is about 80% smaller in width and hight, to
get 1152x900 output we need Horizontal frame length(HFL) of about 1440
and Virtical frame length(VFL) of about 1125 at least.

        HFL = 1440
	VFL = 1125

Then DCF should be

	DCF = RR * HFL * VFL = 116.6 MHz

Well, let's say DCF = 110 MHz. here.

	DCF = 110MHz
	
	

Horizontal Sync


        |___ __ __ __ __ __ __ __ __ __ __ __ __
        |_ _ _ _ _ _ _ _ _ _ _ _                |
        |_______________________|_______________|_____
        0                       ^               ^     unit: ticks
                                |   ^       ^   |
                                HR  |       |  HFL
                                |   |<----->|   |
                                |<->|  HSP  |<->|
                                HGT1         HGT2


    HGT1 and 2 are about 30ticks.
    Take HSP to be 3.8 microseconds at the start point.
    Using 110MHz clock, HSP is 418 ticks.  But 1440-1152 = 288 is much 
    smaller than 418.  So do adjustment as the document says.
    
    How about using 3.5 instead 3.8?  110*3.5 = 385. Lets set HGT1 =
    HGT2 = 32.  1152 +32 +385 +32 = 1601.  Round it to 1600.  Then HSP
    = 384, 3.49 microsecond long.
    

Virtical Synch

   |___ __ __ __ __ __ __ __ __ __ __ __ __
   |_ _ _ _ _ _ _ _ _ _ _ _                |
   |_______________________|_______________|_____
   0                      VR              VFL     unit: ticks
                           ^   ^       ^
                           |   |       |
                           |<->|<----->|
                            VGT    VSP

	Virtical tick is 1600/110MHz = 14.55us.  If we assume virtical
	sync puls of 150us, it will be 10 vertical clock ticks.  So
	VFL is at least 910(=VSF+10).


Mode line

  Probably it looks like this:
  (But I have not tested yet!)

 Bandwidth     110
 HorizSync     71
 VertRefresh   72

 #             < name >       DCF     HR  SH1  SH2  HFL   VR  SV1 SV2 VFL
 ModeLine      "1152x900"     110    1152 1184 1568 1600  900 903 909 930


Actually DCF=110MHz and HFL=1600 produce HorizSync=68.75kHz
(=110Mhz/1600), and refresh rate 73.92Hz (=110Mhz/(1600*930)).