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From: pmacdona@sanjuan (Peter MacDonald)
Subject: X finally up
Date: Tue, 12 May 92 03:14:01 GMT


After about 10 hours of trying, I finally have X up and running.
Except for losing a few chars now and then at 9600 with a large font
scrolling in an Xterm, I have no complaints.  I have an uncached 386/25,
and am using an older (2 years) VGA Morse monitor.

Because so many others seem to be having the same kind of trouble I did,
I will quickly describe my experience:

 1) Forget the timing parameters X reports, they are probably wrong.
 2) Forget the timings "clock" gives, mine were divided by two.
 3) Use "dmode" or whatever utility/manual comes with your video card
    to figure out your clocks.
 4) Try [Vendor "hicolor"] if you have a DAC.
 5) I had to use interlace, because of my slow monitor.
 6) Here is the config I ended with:
================================================================
Microsoft       "/dev/ttys2"
  BaudRate      1200
#  SampleRate   150
  Emulate3Buttons

#
# The graphics drivers
#
vga256
  Chipset "et4000"
  Vendor "hicolor"
  Virtual       1024 1024
  ViewPort      0 0
  Modes "1024x768i"
  Clocks 50 56 72 45 60 65 40 47

ModeDB
# clock  horzontal timing      vertical timing
  "640x480"  56     640  672  768  800    480  490  492  525

  "1024x768i" 45    1024 1064 1224 1264    768  777  785  817   Interlace

From: liljeber@kruuna.Helsinki.FI (Mika Pekka Liljeberg)
Subject: Re: X finally up
Date: 12 May 92 10:22:27 GMT

In article <1992May12.031401.6333@sol.UVic.CA> 
pmacdona@sanjuan (Peter MacDonald) wrote:
> 
> After about 10 hours of trying, I finally have X up and running.
> Except for losing a few chars now and then at 9600 with a large font
> scrolling in an Xterm, I have no complaints.  I have an uncached 386/25,
> and am using an older (2 years) VGA Morse monitor.
> 
> Because so many others seem to be having the same kind of trouble I did,
> I will quickly describe my experience:
> 
>  1) Forget the timing parameters X reports, they are probably wrong.
>  2) Forget the timings "clock" gives, mine were divided by two.
>  3) Use "dmode" or whatever utility/manual comes with your video card
>     to figure out your clocks.

Good advice. I hope other people get good manuals, or a working
diagnostic program. I didn't. :-(

>  4) Try [Vendor "hicolor"] if you have a DAC.

Nope. It's Vendor "hiclock".

After this the clocks reported by clock.exe and X (less reliable) should
work. I had the same problem with my Boca Super X VGA with Sierra DACs.
Without the Vendor line the clocks seemed about double the ones reported.
I ended up with horrid resolutions like 1280x600 (blech!).

I believe that doubling the clock values doesn't actually do anything.
I think that the purpose of the values is just to tie a certain mode
into a certain clock, numbered from 1 to 8 as displayed on the Clocks line.
The actual values just serve to remind the user about the frequency of
the actual clock (correct me, if I'm wrong).

You can test this by changing the line Clocks to:

Clocks 1 2 3 4 5 6 7 8

..and replacing the ModeDB clocks with these as appropriate.

So, the most important thing is to know the proper clock frequencies AND
the order they are in and calculate syncs accordingly.

>  5) I had to use interlace, because of my slow monitor.
>  6) Here is the config I ended with:
> ----------------------------------------------------------------
> Microsoft       "/dev/ttys2"
>   BaudRate      1200
> #  SampleRate   150
>   Emulate3Buttons
> 
> #
> # The graphics drivers
> #
> vga256
>   Chipset "et4000"
>   Vendor "hicolor"

Again, it's "hiclock". Is this a straight copy from your Xconfig? I'm
beginning to wonder, if I've got a different version of X386, or
something. ;-) Amazing. Perhaps they both work...

>   Virtual       1024 1024
>   ViewPort      0 0
>   Modes "1024x768i"
>   Clocks 50 56 72 45 60 65 40 47
> 
> ModeDB
> # clock  horzontal timing      vertical timing
>   "640x480"  56     640  672  768  800    480  490  492  525
> 
>   "1024x768i" 45    1024 1064 1224 1264    768  777  785  817   Interlace

Cheers!

        Mika

--
Mika Liljeberg                  Email:  liljeber@kruuna.Helsinki.FI
Helsinki University                     Mika.Liljeberg@Helsinki.FI
Dept. of Computer Science