[Solved] Looking for BIOS: MBA-386B-25UN \ VOGONS

[Solved] Looking for BIOS: MBA-386B-25UN

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First post, by fgenesis

Posted on 2021-04-22, 18:15

fgenesis Offline

Rank Newbie

Rank: Newbie
Posts: 39
Joined: 2021-04-20, 17:21

I recently obtained an Addonics MBA-386B-25UN mainboard.

The attachment DSC00742.JPG is no longer available

Unfortunately some parts are missing. At least the battery hasn't leaked yet. But it will have to go soon.

I'd like to get this board back into a working state, means i need the BIOS, an AMI keyboard controller, and a 25 MHz 386.
The CPU is easy and I'll probably have one soon, but the BIOS doesn't seem to exist on the internet. UH19 says it's an AMI one but I don't know anything else.
I'm in no particular rush to get this project completed but i'll leave this post here in case in future anyone manages to get hold of a BIOS dump. If you do, please share.
In case this BIOS (or a suitable alternative) turns up I'll edit the post and link it right here.

Since the infos on UH19 are incomplete, here are some more pictures:

The attachment DSC00734.JPG is no longer available

The attachment DSC00738.JPG is no longer available

That's a lot of jumpers there 😮
What's this weird white connector? Haven't seen that one on a mainboard yet.

If anyone has any hints to fix this, or possible alternatives for BIOSes (like a MR-BIOS that saved the day previously) please add your thoughts.
As far as my knowledge about keyboard controllers goes is that it specifically needs to be an AMI one, correct? Since it's supposedly an AMI bios...
Or could a 8042 work as well? Or whatever else is out there?

EDIT: Redirected to new uh19 entry

Last edited by fgenesis on 2021-05-18, 18:43. Edited 2 times in total.

Reply 1 of 2, by Deksor

Posted on 2021-04-22, 19:17

Deksor Offline

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Rank: l33t
Posts: 3423
Joined: 2016-06-07, 14:37

I think a 8042 should work.

In the meantime you could try these testing rom just to see if your board has some life left : http://www.minuszerodegrees.net/supersoft_lan … 0IBM%205170.htm

Trying to identify old hardware ? Visit The retro web - Project's thread The Retro Web project - a stason.org/TH99 alternative

Reply 2 of 2, by fgenesis

Posted on 2021-05-18, 18:43

fgenesis Offline

Rank Newbie

Rank: Newbie
Posts: 39
Joined: 2021-04-20, 17:21

Update: The board is back to life!

An 8042 keyboard controller indeed did the trick. Also found two BIOSes that seem to work. Source info in the zip file.
The original one appears to be an AMI one but I don't have that. The AMI one in the zip may or may not be the original but it's at least for that chipset.
Since there's also a MR-BIOS for the chipset I'll probably roll with that one.

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