PC video problems

PC video problems

[jmk]

One of the biggest problems with Plan 9 on the PC is the awful VGA device and
the equally awful programme to set it up, aux/vga. Here's a quick rundown on what
to do if Plan 9 fails to recognise your VGA card on startup, i.e you are left in
the green-on-black text mode.

If the system hangs on boot before a message from dossrv appears on
the CGA screen then aux/vga blew it. You can prevent aux/vga from running
by commenting out the 'monitor=' line in plan9.ini, /bin/termrc will
only run aux/vga if the environment variable 'monitor' is set.

You will be left in CGA mode. Two warnings about this:

a) make sure you do not start anything fancy (such as a window manager)
   in your lib/profile;
b) DEL is interpreted by the window manager so you will be unable to interrupt
   anything you start.

If you can't get to this state then your PC/VGA just isn't compatible with Plan 9.

1) At the command prompt execute
	aux/vga -pv > /tmp/x
   (you may have to execute ramfs first if you don't have a writeable /tmp yet).
   Aux/vga defaults to 'monitor=vga' and resolution 640x480x1.
   Output is redirected to capture some information during this run while
   still in CGA mode that would be destroyed by the switch to VGA mode. Usually
   this will have the desired effect and the system will be in VGA mode.

2) Look in /tmp/x for any obvious errors. There may be a section which says e.g.

	controller not in ./vgadb
	0xC0000 55 AA 40 EB 04 37 34 30 30 E9 0A 15 00 00 00 00  U.@..7400.......
	0xC0010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 49 42  ..............IB
	0xC0020 4D 20 56 47 41 20 43 6F 6D 70 61 74 69 62 6C 65  M VGA Compatible
	0xC0030 20 42 49 4F 53 2E 20 00 BB 66 DB 01 EF 01 81 00   BIOS. ..f......
	0xC0040 00 FF 00 0A 51 75 61 64 74 65 6C 20 53 33 20 38  ....Quadtel S3 8
	0xC0050 36 43 38 30 35 20 45 6E 68 61 6E 63 65 64 20 56  6C805 Enhanced V
	0xC0060 47 41 20 42 49 4F 53 2E 20 56 65 72 73 69 6F 6E  GA BIOS. Version
	0xC0070 20 32 2E 31 33 2E 30 32 45 30 31 0D 0A 43 6F 70   2.13.02E01..Cop
	0xC0080 79 72 69 67 68 74 20 31 39 38 37 2D 31 39 39 32  yright 1987-1992
	0xC0090 20 51 75 61 64 74 65 6C 20 43 6F 72 70 2E 2C 20   Quadtel Corp., 
	0xC00A0 41 20 50 68 6F 65 6E 69 78 20 54 65 63 68 6E 6F  A Phoenix Techno
	0xC00B0 6C 6F 67 69 65 73 20 4C 74 64 20 43 6F 6D 70 61  logies Ltd Compa
	0xC00C0 6E 79 2E 0D 0A 41 6C 6C 20 52 69 67 68 74 73 20  ny...All Rights 
	0xC00D0 52 65 73 65 72 76 65 64 0D 0A 00 00 00 00 00 00  Reserved........
	0xC00E0 00 00 00 00 4F 72 63 68 69 64 20 54 65 63 68 6E  ....Orchid Techn
	0xC00F0 6F 6C 6F 67 79 20 46 61 68 72 65 6E 68 65 69 74  ology Fahrenheit

   This is a dump of part of the VGA BIOS and can be used to add an entry to
   /lib/vgadb for this card:
	ctlr
		0xC0044="Quadtel S3 86C805 Enhanced VGA BIOS. Version 2.13.02E01"
		ctlr=vga

3) Now try the default vga mode again by executing
	aux/vga -lpv > /tmp/xx
   Again, look in /tmp/xx for obvious errors.

4) With this in place aux/vga should work without complaint for resolutions
   640x480x[18] as these require no additional programming of the graphics chip,
   RAMDAC or clock generator.

To proceed to higher resolutions and clock rates it's necessary to know more about
the VGA card, specifically which graphics chip, RAMDAC and clock generator are
used; inspect the card and see VGADB(6) for more details.

PC video problems

[Hans-Peter]

We found the follwing unhappy things in the new edition.

1.	fcallconv() didn't like the new 9P structure.
2.	The man pages for the commands swap and rx are
	a little bit incorrect.
	
		man swap:	Syntax: swap file
		cmd swap:	Syntax: swap path
		
		man rx: 	Syntax: rx [-n]	 ....
		cmd rx:		Syntax: rx [-e]  ....

-hp

PC video problems

[Jack]

I've been trying to install the ftp-able version and I'm running into a 
strange problem.  After accepting none as the username, I get the following:

init: starting /bin/rc
/bin/dossrv 19: serving #s/dos
init: rc exit status: rc 8:false

init: starting /bin/rc
term%

Sometime during this the screen also changes size, but remains 
text-only.  I never get the windowing system.

Also, if I enter a username (after setting it up, of course) it hangs 
following the second "init: starting /bin/rc".

I assume it has to do with my video card.  It's a Cirrus Logic-based card 
on the motherboard (of an HP Vectra VL2), and Windows '95 tells me that, 
although it works, "The resources this device is using does not match any of 
its known configurations."  I know the gang at AT&T has had success with 
Cirrus Logic cards on the motherboard, so I'm hoping someone out there 
has run into this problem already.

Any help would be GREATLY appreciated!

-Jack Johnson
 fsjdj1@aurora.alaska.edu