VOGONS


First post, by citronalco

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Has anybody here a Schneider Tower AT?
I own a Schneider Tower AT 260 (286 with 12.5 MHz). It's a really nice machine, but I've serious trouble getting any Sound Blaster (or compatible) card to work.
I suspect the BIOS is somewhat faulty, causing DMA timing issues.

My machine has BIOS 1.05a. From pictures on the internet I've learned that there must be at least two newer BIOS revisions: 1.06 and 1.08.
Can someone here with a Tower AT and any newer BIOS than 1.05a post dumps? I think it can be from any Tower AT model as the hardware is always the same.

I've attached my dumps of the two BIOS ROMs (High and Low). I would be very happy if someone could help me.

Reply 1 of 11, by seob

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That's a nice looking machine. First time i see one. We had a Schneider cpc-464 as our first homecomputer, but we bought that in Germany. In the Netherlands Schneider was only known for their hifi sets. My first hifi set was also a schneider.

Reply 2 of 11, by florianix

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I've got 3 Schneider Tower AT systems.

- 2 System 240 (286/10MHz), both non-operational because of (supposedly) dead DALLAS RTCs and also PSU (in one case).
- one System 386 (386SX/16MHz).

Can't access/open one of the 240s (should be the newer one of them) to look for the bios revision, the other (older?) one is version 1.07.
The 386 seems to have a completely different MB layout and the BIOS chips are labeled "386 bios", so they won't work.

Hope to be able to read the ROM-chips soon, but that can take a while:
Need a PC with parallel port first (only have EEPROM programmer with that interface). And still no success with reviving the old machines for that (see Asus P3C-D thread)... 🙁

EDIT: Just found a Soundblaster (very first version) in the open machine that I used in it for years. So there is at least no general problem with that combination.

Reply 3 of 11, by florianix

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Just remembered another point:
The Schneider Tower AT machines can overclock the ISA-bus.
As far as I remember there are two option in the BIOS: Full CPU clocks of 1/2 the CPU clock (10MHz or 5 MHz in my case for the 10MHz version). The standard clock is only 8 MHz. Many cards have issues with higher clock rates. I had huge problems to get some early ethernet cards working with 10MHz bus clock.

Did you try 6.25 MHz bus clock?

Reply 4 of 11, by citronalco

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Yes, Soundblaster are supposed to work.
And yes, some cards have trouble with 12,5 MHz bus speed, e.g. Trident VGA cards: They tend to start in monochrome mode with 12,5 MHz. But using 6,25 MHz does not help anything with the Soundblasters: As soon as a sample should be played the machine freezes. IRQ, DMA and port settings are ok (means: free). And no other ISA cards are plugged in.
It must be the early BIOS revision.

florianx, great to hear you've got a 1.07. I hope I can get this baby working soon!

Reply 5 of 11, by matze79

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Maybe someone from the dosforum.de site can help you out,
There are many Owners in the German Community.
I'm pretty sure one is willing to dump it's rom for you.

https://www.retrokits.de - blog, retro projects, hdd clicker, diy soundcards etc
https://www.retroianer.de - german retro computer board

Reply 6 of 11, by citronalco

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dr.zeissler from http://forum.classic-computing.de was kind enough to create a BIOS dump of 1.07 for me.
I've split it into High and Low parts for the two EPROMS.

Reply 7 of 11, by Jo22

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Hello people,
I've got my Tower AT since a few days and try fixing it.
I got no picture yet, but the PSU seems working fine so far.
Anyway, I was making backups from the EPROMS while doing so.
What I got was an image of rev. 1.01 (low, high). Board is rev. 2A.

I know you're looking for recent versions of the firmware,
but maybe this old one can be useful for testing purposes someday.
I've included the EGA firmware aswell.

"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel

//My video channel//

Reply 8 of 11, by citronalco

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dr.zeissler from http://forum.classic-computing.de uploaded 2.01A there.

Euro AT and Tower AT use the same BIOS, regardless of EGA or VGA.

Reply 9 of 11, by Jo22

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Hello everyone!
Sorry to revive an almost a year old thread, but I've got a reason for this..
Just recently I've got some Schneider parts again and was able to retrive the firmware.
So I thought it was worth to attach another BIOS version here..
The BIOS version is 1.06 from December '88.

This version is special, because it doesn't seem to like VGA cards for some reason (if EGA is also present).
Well, at least I think so: I was unable to get any picture with this in a Schneider Tower with on-board EGA.
And with v2.01A or a BIOS from AMI, that problem went away..

"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel

//My video channel//

Reply 10 of 11, by Lyawon

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Hi, All.
Is anyone have the BIOS dump for Schneider VGA Tower AT system 40 more recent version than v2.01a?

Reply 11 of 11, by Lyawon

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Schneider VGA Tower AT BIOS v2.03 here: Re: 80286 BIOS image collection
"User type" for HDD avaliable with v2.03