What in the world is up with this chip on this Unisys 486 board? Pic attached... \ VOGONS

What in the world is up with this chip on this Unisys 486 board? Pic attached...

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First post, by 9646gt

Posted on 2020-04-09, 01:33

9646gt Offline

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Just bought a Unisys SG3400 with a board that has AMI BIOS and a UMC chipset. I noticed one of the chips, not exactly sure what this chip is, has what I am not 100% is a modification or is an original job done at the factory. What has been done with this chip? I can provide details from the text on it if I get back around to opening it up again over the next few days...

https://photos.app.goo.gl/CusK1JxWWb7tNFxi9

Reply 1 of 3, by pentiumspeed

Posted on 2020-04-09, 01:41

pentiumspeed Offline

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Keyboard controller IC (microcontroller), with tiny 8 bit cpu and tiny memory, some ROM on one die.

This modifications I see this often with IBM produced boards as well.

Cheers,

Great Northern aka Canada.

Reply 2 of 3, by 9646gt

Posted on 2020-04-09, 01:43

9646gt Offline

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Wow! Thanks for the quick reply! I have never seen something like this on a factory board, I guess things were more wild west than I remember haha. Thanks again!

Reply 3 of 3, by Horun

Posted on 2020-04-09, 01:55

Horun Offline

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My guess is that the KB controller was not getting good clock signals from main board so it was modified. Good pics !

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

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