Hello all,
I've made a simple 16-bit DOS program cycling thru all video-modi from 00h upto 7Fh and output (redirected to file) the effective video modus and what the width and height of each is (looking in the 0040:xxxx memory segment). Which seems to work alright (I get a full list). (remark: I've already excluded the "special" and "reserved" video modi)
But switching back to the desktop (from a full-screen DOS window) goes
wrong: All I see is a black screen with the mousepointer (which I can move), and after a few seconds the 'puter reboots. :-(
I think I've isolated the offending video-modus to 5Ch. The problem with it is that RBIL doesn't show that mode as being special or reserved. Also, the output shows it being a valid modus (0040:0049) and the resolution seems to be alright too (1920x1440)
Remark: video modus 4Dh (with the same, highest resolution) doesn't cause a problem (though RBIL doesn't mention the returned resolution ...).
My questions:
1) Does anyone know how/why video-mode 5Ch causes XP to malfunction
2) Is there a DOS, INT10h way to check if a video-modus is acceptable other than to try it and see the 'puter crash ?
I just realised: it could have something to do with the ammount of colors (read: ammount of needed video memory), but a quick look doesn't show any such info being stored in the 0040:xxxx memory segment.
Regards,
Rudy Wieser
1) it's VENDOR specific:...
and perhaps your graphic chip doesn't have it.
2) VESA is your friend here, it can list all available modes and also if asked it reports in deep detail what a certain mode is able
to do.
look at INT 10_4F_00...
But what I get is this (below memory adresses have been set to -1 before switching video modus):
Video mode set: 5C
0040:0049=5C
0040:004A=000F0
0040:0084=5A
0040:0085=0010
I've got more problems though: I tried to set mode 30h, 32h and 34h, but
that trashes text (it gets horizontally smeared out), it doesn't seem to
want to plot pixels (INT 10h, AH=0Ch BH=00h) and enableing the mouse (INT 33h, ax=0001h) causes an NTVDM unrecognised instruction crash. :-|
In short, I have no idea what exactly is going on, but it looks that my 'puters integrated video card doesn't match its BIOS. :-( (its an Dell Optiplex 745)
That's definitely a custom video mode. Not yet listed in RBIL.
Have you tried running the test from pure DOS?
I suggest you check the video BIOS. e.g. with DEBUG command:
And if you don't mind, share the BIOS.
Not on the XP machine (the partitions are too big for true DOS).
Below are the strings that I found :
0000:0010 30 30 9C 18 E9 8D 17 00 40 00 B0 0A 30 30 49 42 '00..笮.@.°.00IB' 0000:0020 4D 20 56 47 41 20 43 6F 6D 70 61 74 69 62 6C 65 'M VGA Compatible' 0000:0030 20 42 49 4F 53 2E 20 03 5A 00 6A 00 78 00 8B C0 ' BIOS. .Z.j.x..� ....
0000:0AB0 24 56 42 54 20 42 52 4F 41 44 57 41 54 45 52 2D '$VBT BROADWATER-' 0000:0AC0 47 20 20 20 64 00 30 00 37 07 81 00 30 00 00 00 'G d.0.7...0...' 0000:0AD0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 '................' 0000:0AE0 42 49 4F 53 5F 44 41 54 41 5F 42 4C 4F 43 4B 20 'BIOS_DATA_BLOCK ' ....
0000:0B90 00 00 00 00 00 00 00 00 00 00 00 00 00 00 43 6F '..............Co' 0000:0BA0 70 79 72 69 67 68 74 20 28 43 29 20 32 30 30 30 'pyright (C) 2000' 0000:0BB0 2D 32 30 30 33 20 49 6E 74 65 6C 20 43 6F 72 70 '-2003 Intel Corp' 0000:0BC0 2E 20 41 6C 6C 20 52 69 67 68 74 73 20 52 65 73 '. All Rights Res' 0000:0BD0 65 72 76 65 64 2E 0D 0A 0D 0A 00 00 C0 03 08 04 'erved.......�..' ....
0000:0F90 00 00 00 00 00 00 00 00 0B A6 00 21 30 00 52 60 '.........¦.!0.R`' 0000:0FA0 53 49 2D 31 33 36 32 2D 41 00 00 00 01 05 70 1D 'SI-1362-A.....p.' ....
0000:5390 49 6E 74 65 6C 28 72 29 42 72 6F 61 64 77 61 74 'Intel(r)Broadwat' 0000:53A0 65 72 2D 47 20 47 72 61 70 68 69 63 73 20 43 68 'er-G Graphics Ch' 0000:53B0 69 70 20 41 63 63 65 6C 65 72 61 74 65 64 20 56 'ip Accelerated V' 0000:53C0 47 41 20 42 49 4F 53 00 49 6E 74 65 6C 20 43 6F 'GA BIOS.Intel Co' 0000:53D0 72 70 6F 72 61 74 69 6F 6E 00 49 6E 74 65 6C 28 'rporation.Intel(' 0000:53E0 72 29 42 72 6F 61 64 77 61 74 65 72 2D 47 20 47 'r)Broadwater-G G' 0000:53F0 72 61 70 68 69 63 73 20 43 6F 6E 74 72 6F 6C 6C 'raphics Controll' 0000:5400 65 72 00 48 61 72 64 77 61 72 65 20 56 65 72 73 'er.Hardware Vers' 0000:5410 69 6F 6E 20 30 2E 30 00 60 01 61 01 62 01 63 01 'ion 0.0.`.a.b.c.'
It doesn't tell /me/ anything I can use though :-) What is it telling you ?
I don't mind. Though I'm not so sure that putting a binary dump like the above or base64 encoded into a newgroup message would be a good idea. So, where (email) do you want me to send it to ? (due to JS being disabled on my 'puter it doesn't play nice with most filesharing servers. And for one-off drops I don't like to register either)
You can create a bootable USB thumb drive, or bootable
CDROM; with DOS in it.
Windows' VGASAVE driver
AFAIK, Intel video adapters are known to be mediciore ones, including
the current 3D GPUs. So, I wouldn't be surprised if the hardware or its
BIOS has bugs.
But it's no longer necessary since you've posted filtered BIOS data
to include only meaningful strings.
Sysop: | Keyop |
---|---|
Location: | Huddersfield, West Yorkshire, UK |
Users: | 415 |
Nodes: | 16 (2 / 14) |
Uptime: | 54:43:23 |
Calls: | 8,728 |
Calls today: | 1 |
Files: | 13,276 |
Messages: | 5,958,441 |