Author Topic: AT 2 XT (Read 2361 times)

DaCiRo · « **on:** Wed, 08 October 2014, 07:20:19 »

Hi
I am trying to connect an IBM AT keyboard (84 keys) to an IBM 6\5160 XT machine, but I keep on getting the famous '301' error that confirms that there is no keyboard detected.
I am aware that the IBM keyboard versions AT and XT use different scan codes however there must be a way to make the IBM AT keyboard to simulate the XT scan codes.
Does anyone know if this can be done directly into the keyboard controller through software or is the only one to do it through some type of physical converter (and...where can I get one?)

E TwentyNine · « **Reply #1 on:** Wed, 08 October 2014, 07:53:15 »

I believe an IBM AT keyboard should be backward compatible to an XT. The M's are.

If no one comes up with a definitive answer I can set up my 5160 and plug in an AT and see what I get...

DaCiRo · « **Reply #2 on:** Wed, 08 October 2014, 08:02:47 »

Thanks for suggesting. I also assumed that it would work,...but doesn't seem to be the case. I tried rebooting and plugging-unplugging, ... no luck
I however can connect any of the IBM Model Ms including the IBM Space Saver.

hwood34 · « **Reply #3 on:** Wed, 08 October 2014, 08:12:45 »

Are you using an active PS/2 to USB converter?

DaCiRo · « **Reply #4 on:** Wed, 08 October 2014, 08:29:30 »

This is 5 pin cable (not USB) connected directly into the keyboard port of the motherboard.

hwood34 · « **Reply #5 on:** Wed, 08 October 2014, 08:36:40 »

Quote from: DaCiRo on Wed, 08 October 2014, 08:29:30

Show Image

This is 5 pin cable (not USB) connected directly into the keyboard port of the motherboard.

Hmm, well that's all I got. Aren't ATs supposed to be able to communicate without anything else but a converter?

DaCiRo · « **Reply #6 on:** Wed, 08 October 2014, 08:43:45 »

I would think so, my other AT keyboards work, but for some reason the 84 key it is not recognized by the system (

)

DaCiRo · « **Reply #7 on:** Wed, 08 October 2014, 09:00:33 »

The IBM SpaceSaver (1st picture) gets detected no problem
The IBM AT 84 keys (2nd picture) doesn't get detected.... been trying few times with the same results.

DaCiRo · « **Reply #8 on:** Wed, 08 October 2014, 09:03:24 »

sorry.

1st picture (S

pace Saver)
2nd picture (AT 84 keys)

DaCiRo · « **Reply #9 on:** Wed, 08 October 2014, 09:05:01 »

Whatever the F@@#$%! order,... I can't get it right.

E TwentyNine · « **Reply #10 on:** Wed, 08 October 2014, 10:00:47 »

Quote from: hwood34 on Wed, 08 October 2014, 08:12:45

Are you using an active PS/2 to USB converter?

He's going against a 5160, an XT computer. USB was a long long ways away at that point.

JPG · « **Reply #11 on:** Wed, 08 October 2014, 10:07:09 »

Why not buy a IBM XT keyboard? They are the most easy to find and most cheap.

DaCiRo · « **Reply #12 on:** Wed, 08 October 2014, 10:12:50 »

I don't think I can get used to the small enter key of an XT keyboard, I am not too fan of the overall layout of the keys.
Also I would not be able to use it in any other system without a special XT to AT adapter, so basically it is a keyboard slave of XT systems only, while the AT keyboard is compatible with all other systems,... except I cant make it work in my XT

JPG · « **Reply #13 on:** Wed, 08 October 2014, 10:24:27 »

Quote from: DaCiRo on Wed, 08 October 2014, 10:12:50

I don't think I can get used to the small enter key of an XT keyboard, I am not too fan of the overall layout of the keys.
Also I would not be able to use it in any other system without a special XT to AT adapter, so basically it is a keyboard slave of XT systems only, while the AT keyboard is compatible with all other systems,... except I cant make it work in my XT

They both work very well with modern computer with a Soarer converter using USB!

Do you use this old computer that much?

DaCiRo · « **Reply #14 on:** Wed, 08 October 2014, 10:40:18 »

I use it almost everyday. I do a lot of document typing with it.
The soarers converter is a great solution, specially to make this boards work in modern systems. I just want the AT to work in my old XT system and there must be a way for it I am sure.

hwood34 · « **Reply #15 on:** Wed, 08 October 2014, 10:44:51 »

Quote from: E TwentyNine on Wed, 08 October 2014, 10:00:47

Quote from: hwood34 on Wed, 08 October 2014, 08:12:45
Are you using an active PS/2 to USB converter?

He's going against a 5160, an XT computer. USB was a long long ways away at that point.

Oh, hah, didn't read the OP closely enough

E TwentyNine · « **Reply #16 on:** Wed, 08 October 2014, 13:07:20 »

I fired up my 5160 and it works fine with an XT keyboard. With an AT keyboard I get the 301. The LED's did flash which was actually a little surprising to me.

I don't believe there's anything that can be jumpered inside an AT keyboard to get it to talk XT.

dorkvader · « **Reply #17 on:** Wed, 08 October 2014, 13:58:34 »

I remember reading about this before. I will do some research and see if I can find anything, but I think E TwentyNine may be correct.

I do know that the AT keyboard was set up differently than other IBM (and other AT) keyboards at the time. I thought it had XT capabilities and would auto-switch somehow (like the model Ms do) but I don't remember any specifics.

Again. I will poke around a little then get back to you.

edit: what bios version does your XT have?
http://www.vintage-computer.com/vcforum/showthread.php?17677-IBM-model-M-on-a-IBM-XT-machine

edit2:
here we go:
http://geekhack.org/index.php?topic=6916.msg111915#msg111915

So probably not, unless it's an XT 286 (which is more like an AT in an XT box I guess). Because of that you might be interested in either a model M (most or all should work with your XT, and the 1390120 certainly will) or this converter:
http://www.vintage-computer.com/vcforum/showthread.php?15907-AT-to-XT-Keyboard-Converter

DaCiRo · « **Reply #18 on:** Thu, 09 October 2014, 08:47:42 »

E29, Dorkvader
Thank you very much for your help. E29 for testing the AT at you end and Dorkvader for all the links with such good information, really appreciated.
it seem then that this is not going to be possible (what a bummer!).

Do you think that a soarers converter somehow would do the trick. I have heard about them but mostly for USD conversion, from for a 5pin XT to 5pin AT.

dorkvader · « **Reply #19 on:** Thu, 09 October 2014, 10:08:19 »

soarer's converter (info at the link below) only converts things to USB
http://geekhack.org/index.php?topic=17458.0

You might want to check with the guys on vintage computer forums about this converter though:
http://www.vintage-computer.com/vcforum/showthread.php?15907-AT-to-XT-Keyboard-Converter

DaCiRo · « **Reply #20 on:** Thu, 09 October 2014, 10:16:52 »

Thanks Dorkvader.
Reading through it right now...

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Author Topic: AT 2 XT (Read 2361 times)