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IBM Model M Keyboard with an XT
- Thread starter marcoguy
- Start date
Chuck(G)
25k Member
Depends on the Model M--earlier ones can auto-detect the XT protocol. Later ones cannot.
You can always get an AT-XT keyboard converter from Hargle--they're cheap and they work with almost any PS/2-interface keyboard.
You can always get an AT-XT keyboard converter from Hargle--they're cheap and they work with almost any PS/2-interface keyboard.
Well, I have what has to be the world's crappiest model M with a switch for AT/XT. I really want an IBM one. I've got an 83 key IBM one that I disassembled earlier today to clean and accidentally went a little too far and got all 83 of the little plastic things under the keys with the spring on them out of order. Once I got them back in order, I tested it and found that the N key didn't work. I took off the key and saw that the spring had become detached. I now have to take it apart again and realign all of the little plastic things again and fix that spring... Well, what I have realized is that my entire keyboard is caked with dirt on the inside and it probably won't last very much longer. The crappy keyboard would be okay until I got a replacement, but if I would probably sell my system before staying with that keyboard long term. I really just want to get a replacement keyboard and feel that I may as well get an old model M.
I might be able to get one for you from a guy who has a stack of model M's. I think they all have the caps/scroll/num lock LEDs so they might not be the right models. I have opened one up and on the chip was (c) 1984, so maybe there was one model with the LEDs that could still switch between XT-AT.
kishy
Veteran Member
The early part numbers 1390120/1390131 and language variants are XT autosensing capable (1390120 actually shipped with/for XTs, hence the lack of LEDs). The same goes for at least 'some' 1391401 and language variants.
(example of a language variant: 1391406 is a different layout version of 1391401)
The 83-key "Model F" will outlast you and 3+ more generations to come. Take it apart and clean it up - they're well worth the care, especially partnered with a converter so you can use them on more than just vintage boxes.
(example of a language variant: 1391406 is a different layout version of 1391401)
The 83-key "Model F" will outlast you and 3+ more generations to come. Take it apart and clean it up - they're well worth the care, especially partnered with a converter so you can use them on more than just vintage boxes.
Great Hierophant
Veteran Member
LEDs don't matter, even the LEDless Model Ms have header on their circuit board for a ribbon cable from where the LEDs go. If the keyboard supports the XT protocol, the keyboard will work but the system will just simply not be able to light them up. Model ##s matter.
Amen to that. I have found that 1391401s made by IBM, 1985-1992, work just fine. Anything made by third parties like Lexmark, Unicomp and the like, I do not know. If you don't want to have to find a converter box, the 84-key AT keyboard is also built like a tank.
Ah, ok. I thought that the presence of LEDs meant that it was AT only so I never tested it with an XT machine. I'll check with the guy this weekend to see if he still has them. I'm almost certain that they're all 1391401s made in the late 80s.
Stone
10k Member
I've got several Model Ms, some with and one without the LEDs and they all work with my XT. They're also all from 1986 and 1987.
Chuck(G)
25k Member
Model M's are pretty much indestructible in my experience. I've got about 10 of them in various vintages and brands (the one I'm typing this on says "Wang" and is a 13977721). I've never had any fail on me, even with aggressive daily use.