Re: [9fans] Monitors and VGADB

Re: [9fans] Monitors and VGADB

[Mark_Otto]

I have gotten replies to my post but nothing about making a VGADB monitor
entry.  The vertical frequency is not a typo.  I'll let you know or post
something if there is a change.

Mark





William Staniewicz <wstanREMOVETHIS@planet.nl>@cse.psu.edu on 08/21/2000
05:37:07 AM

Please respond to 9fans@cse.psu.edu

Sent by:  owner-9fans@cse.psu.edu


To:   9fans@cse.psu.edu
cc:

Subject:  Re: [9fans] Monitors and VGADB


Mark,

I just installed Plan9 on my pc yesterday. I have the same monitor as you
do
and used the vgadb entry for the Micron 17FGx. This is probably not the
correct
thing to keep running it but at least it got something up on the screen for
me
to work with. I looked at my user's manual for the Micron 700FGx and
noticed a
difference in one of the numbers you posted. I wasn't sure if it is a typo,
but
what I have is indicated below. BTW, if you got any replies to your posting
I would
be interested in how to modify my vgadb correctly too.

/Bill
wstanREMOVETHIS@planet.nl

On Fri, Aug 18, 2000 at 04:14:15PM +0000, Mark C. Otto wrote:
> I have a Micron 700FGx 17" monitor, and I was trying to work through the
> second part of the vgadb(6) to see if vga(8) will recognize my monitor.
> I found an entry in the database for a Micron 17FGx.  I cannot figure
> out how to go from the information in the monitor manual to VGADB entry,
> Display           300x225mm of viewable area.
> Dot pitch         0.26mm (gives only one and does not specify horizontal
or
> vertical)
> Horizontal frequency   30.0-69.0kHz
> Vertical frequency     50.0-160.0Hz <--- I have 50.0-120.0
> Video band width  86MHz
> Maximum resolution     1280x1024@60Hz
> Preset modes:

Re: [9fans] Monitors and VGADB

[William Staniewicz]

Mark,

I just installed Plan9 on my pc yesterday. I have the same monitor as you do
and used the vgadb entry for the Micron 17FGx. This is probably not the correct
thing to keep running it but at least it got something up on the screen for me
to work with. I looked at my user's manual for the Micron 700FGx and noticed a
difference in one of the numbers you posted. I wasn't sure if it is a typo, but
what I have is indicated below. BTW, if you got any replies to your posting I would
be interested in how to modify my vgadb correctly too.

/Bill
wstanREMOVETHIS@planet.nl

On Fri, Aug 18, 2000 at 04:14:15PM +0000, Mark C. Otto wrote:
> I have a Micron 700FGx 17" monitor, and I was trying to work through the
> second part of the vgadb(6) to see if vga(8) will recognize my monitor. 
> I found an entry in the database for a Micron 17FGx.  I cannot figure
> out how to go from the information in the monitor manual to VGADB entry,
> Display			300x225mm of viewable area.  
> Dot pitch		0.26mm (gives only one and does not specify horizontal or
> vertical)
> Horizontal frequency	30.0-69.0kHz
> Vertical frequency	50.0-160.0Hz <--- I have 50.0-120.0
> Video band width	86MHz
> Maximum resolution	1280x1024@60Hz
> Preset modes:

Re: [9fans] Monitors and VGADB

[Scott Schwartz]

| does anyone know
| how it did that?  i thought the video output
| cable was one-way.

No, modern monitors use "DDC" to communicate their vital data back to
a DDC compatable video card.

There's a linux program that supposedly exercises this, but I didn't
have much luck with a Nokia 447x talking to a #9 771.

http://altern.org/vii/programs/linux/read-edid/ 

Re: [9fans] Monitors and VGADB

[Matt]

>  does anyone know
> how it did that?  i thought the video output
> cable was one-way.

DDC

and I'm pleasantly surprised to know something Russ didn't know


that's like something I can tell people about :-)

Re: [9fans] Monitors and VGADB

[Matt]

> an odd side-note: i plugged my (real) hitachi cm751u
> into a win98 box the other day, and the win98 box
> figured out that it was connected to a "Hitachi CM751"
> (new hardware detected!, etc.).  does anyone know
> how it did that?  i thought the video output
> cable was one-way.

DDC
Short for Display Data Channel, a VESA standard for communication between a
monitor and a video adapter. Using DDC, a monitor can inform the video card
about its properties, such as maximum resolution and color depth. The video
card can then use this information to ensure that the user is presented with
valid options for configuring the display.



http://webopedia.internet.com/TERM/D/DDC.html

Re: [9fans] Monitors and VGADB

[Russ Cox]

aux/vga won't recognize your monitor
per se, but if you set monitor=micron-17FGx you
should be all set.  i've been using a micron
monitor with the cm751u defn to run at 1600x1200
and it works fine (yes it's a hack).

an odd side-note: i plugged my (real) hitachi cm751u
into a win98 box the other day, and the win98 box
figured out that it was connected to a "Hitachi CM751"
(new hardware detected!, etc.).  does anyone know
how it did that?  i thought the video output
cable was one-way.

for translation from the manual to the
numbers needed by vgadb, the best reference
i know of is the XFree86 Video Timings HOWTO
(formerly the Hitchhiker's Guide to X386
Video Timings).

http://www.linuxdoc.org/HOWTO/XFree86-Video-Timings-HOWTO.html

russ

[9fans] Monitors and VGADB

[Mark C. Otto]

I have a Micron 700FGx 17" monitor, and I was trying to work through the
second part of the vgadb(6) to see if vga(8) will recognize my monitor. 
I found an entry in the database for a Micron 17FGx.  I cannot figure
out how to go from the information in the monitor manual to VGADB entry,
particularly how to get shb, ehb, ht, vrs, vre, vt, hsync, and vsync. 
Since the VGADB specifications are in terms of character clocks, this
seems to be from the generation of character terminals, which I cannot
find a description of.  I have been reading the PC Upgrade Bible to get
an idea of how the video cards and monitors work.  Ferraro, Richard E.,
Programming Guide to the EGA, VGA and Super VGA Cards is out of print.  

Could someone could give me a time period in the 9fans archives or an
another book or article that would explain how to go from a monitor
description like the one below to a VGADB monitor entry.  Russ has
talked about updating the graphics part of Plan9, but until then some
conversion formulas would help, especially when I do not have the system
installed to experiment with it. 

Thanks for any references or information someone can provide.
Mark Otto



Display			300x225mm of viewable area.  
Dot pitch		0.26mm (gives only one and does not specify horizontal or
vertical)
Horizontal frequency	30.0-69.0kHz
Vertical frequency	50.0-160.0Hz
Video band width	86MHz
Maximum resolution	1280x1024@60Hz
Preset modes:

					Frequency		Signal Polarity
Mode		Resolution	Horzontal	Vertical	Horz	Vertical
VGA 480@60Hz	640x480		31.47kHz	59.94Hz		-	-
640x480@75Hz	640x480		37.50kHz	75.00Hz		-	-
800x600@75Hz	800x600		46.88kHz	75.00Hz		+	+
832x624@75Hz	832x624		49.73kHz	74.55Hz		-	-
1024x768@70Hz	1024x768	56.48kHz	70.07Hz		-	-
1024x768@75Hz	1024x768	60.24kHz	74.93Hz		-	-
1024x768@75Hz	1024x768	60.02kHz	75.03Hz		+	+
1280x1024@60Hz	1280x1024	63.98kHz	60.02Hz		+	+

There is no mention of interlacing in the monitor manual.