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IBM AT Keyboard, or Model F

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bettablue

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So is there any real difference between AT keyboard as supplied with the IBM 5150 PC, and 5160 PC/XT computers, and the Model F? What are those differences and do those differences even matter? Also, I know that early 5170 PC/AT computers came with an AT keyboard, but later ones came supplied with a Model M keyboard. Does that mean the Model M can be also used with either the 5150, and 5160 computers?

I personally like the Model M much better than I do the AT style, as the 101 key layout the Model M introduced, has become the standard of the industry. If possible, and just in my computer/hobby room, I have an extra Model M I would like to use while working on some of the IBM computers I either have, or will soon have. It would be nice just to have a standard location for the different keys. And other than the function keys, and the idea that the Model M doesn't have a F11, or F12 doesn't seem to be an issue; at least so far.
 
Just to clear up the keyboards,

5150 - shipped with 84 key Model F - XT protocol
5160 - originally shipped with 84 key Model F - XT protocol
5170 - originally shipped with 84 key Model F - AT protocol

So if a keyboard works on a 5170, we can't assume it'll work on a 5150 or 5160.

101 key Model M was available in many variants. Some earlier models will auto-sense and change between XT or AT protocols as needed.
Someone here suggested that Model M's with the square logo are likely to support XT's, but ones with the more modern round logo on the left are unlikely. I wouldn't know for sure.

The difference between the XT and AT standards was the protocol and signaling - one enhancement was the ability for the computer to send instructions to the keyboard like turning on or off the LEDs.
I've used XT compatible 101 key keyboards on my 5150 256K, 5160 256K, and 5160 640K models without problem - although I think the later BIOS revision on the 640K model provides better support for all keys.
 
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Thanks for the quick response.

Actually, when I was explaining the missing F11 and F12 keys, I was referring to the Model M. The Model M never did have either of those keys.

Now, you mention that the possibility of a Model F missing the F11 and F12 keys, I believe is erroneous, as I have had a couple of AT keyboards, a Model F, and currently own a couple Model M's. I have never seen a Model F missing those two keys, as the Model F had it's function keys in the exact same layout as the AT style keyboards. Indeed, if there were no labeling on the bottom of the keyboard to state which model it was, there would really be no way to just look at the keyboard and say, "Yeah, that's an AT", or "that's a Model F"

I am interested in the protocols you mention though. I didn't realize the Model F used either the AT, or XT protocols.

When my "new" 5150 arrives, I'm definitely going to try connecting my Model M to it, to see if it will work. From what I understand, most model M's were auto switching, so it should work as soon as the computer is booted. If not, then I'll have learned something, and I'll have to buy a keyboard specifically for the 5150.
 
I think you might have them mixed up :)

Model F - F1 to F10 on the left - total of 84 keys
XT Version that shipped with 5150/5160: http://www.clickykeyboard.com/2013/feb02/001.jpg
AT Version that shipped with 5170: http://cpkey.com/wp-content/uploads/2013/09/IBM-Model-F-1024x447.jpg (think this also came without the LEDs too)


Model M - F1 to F12 on the top - total of 101 keys
http://www.knizefamily.net/russ/blog/wp-content/uploads/2012/01/keyboard-model-m-1.jpg

There were special versions with more keys, but those are the ones IBM shipped with general PCs.

My favorite is clone keyboards with the Model M layout, but the Model F click :)

Edit: oh and with the Model F keyboards, IBM labelled them "Personal Computer", "Personal Computer XT", and "Personal Computer AT". Clones often had an 8088/80286 or XT/AT switch and some like my Commodore 101 key keyboards auto-sensed. Later model keyboards though had no labelling, switch or autosense, so you often get people going 'why wont this work on my XT???'.
 
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Stupid me! I did get them reversed. Sorry for the confusion. The Model M HAS always had the F11 and F12 keys, it's just that they are unused when connected to either a 5150 PC, 5160 PC/XT. Regardless which revision, the 5170 PC/AT seemed to support either the Model F, or Model M keyboards. Model F keyboards don't have the F11 and F12 keys. That still begs the question; What are the real differences between the Model F, and AT style keyboards, or are ALL AT and XT keyboards Model F's?

Thanks for the clarification, and you were absolutely right. I did have my boards mixed up.

SpidersWeb said:
I think you might have them mixed up :)

Model F - F1 to F10 on the left - total of 84 keys
XT Version that shipped with 5150/5160: http://www.clickykeyboard.com/2013/feb02/001.jpg
AT Version that shipped with 5170: http://cpkey.com/wp-content/uploads/2013/09/IBM-Model-F-1024x447.jpg (think this also came without the LEDs too)


Model M - F1 to F12 on the top - total of 101 keys
http://www.knizefamily.net/russ/blog/wp-content/uploads/2012/01/keyboard-model-m-1.jpg

There were special versions with more keys, but those are the ones IBM shipped with general PCs.

My favorite is clone keyboards with the Model M layout, but the Model F click :)

Edit: oh and with the Model F keyboards, IBM labelled them "Personal Computer", "Personal Computer XT", and "Personal Computer AT". Clones often had an 8088/80286 or XT/AT switch and some like my Commodore 101 key keyboards auto-sensed. Later model keyboards though had no labelling, switch or autosense, so you often get people going 'why wont this work on my XT???'.
Click to expand...
 
The 5150, 5160, and 5170 all originally shipped with Model F keyboards - but the version for the 5170 had used a different keyboard interface chip and some had Caps Lock, Num Lock, and Scroll Lock LEDs.
The 5170 only supports AT keyboards - you can't use XT keyboards on them - even if they're Model F.

The term "Model F" really describes the physical characteristics only. I have a Model M keyboard for my RT which has a speaker built in and an "Action" key. Completely oddball, but it's still called a Model M by IBM.

The "AT" keyboard standard stuck, so it's easy to find a keyboard that'll work on a 5170. Almost any PS/2 keyboard (even models with Windows keys) will work on a 5170 or higher.
On a 5150 or 5160 it's a bit more of a pain because of the old interface.

There was an AT-to-XT project on here a while ago I'm sure, hopefully those guys can provide the real technical differences. But as an end user, the only thing that annoyed me about the old XT interface was that the computer could never set the Caps, Num, or Scroll lock lights. So if software turned CAPS lock on, the light would stay off, then you'd press the key to turn CAPS lock off, and the light would turn on! I can say though that I regularly use 101 key keyboards on my PC, XTs, and clones - as long as they support that old XT interface - they do the job fine.

Edit: I hope that helps, I worry that I keep making it more confusing lol
 
SpidersWeb said:
Just to clear up the keyboards,

5150 - shipped with 84 key Model F - XT protocol
5160 - originally shipped with 84 key Model F - XT protocol
5170 - originally shipped with 84 key Model F - AT protocol....
Click to expand...
That doesn't take into consideration the Model F with 83 keys. I know they exist 'cause I have one.
 
SpidersWeb said:
Just to clear up the keyboards,

5150 - shipped with 83 key Model F - XT protocol
5160 - originally shipped with 83key Model F - XT protocol
5170 - originally shipped with 84 key Model F - AT protocol.
Click to expand...

Fixed that. Unless you have a non-IBM board the 84s are AT and the 83s are PC/XT.

The other Model F boards are harder to find - 122s terminal boards, 5291 board, 3178 board, etc. One The 122 boards however can be converted to work over USB with an adapter that doesn't require destruction of the board.
 
JohnElliott said:
You can, actually. Use KBXT to put the 5170's keyboard controller into XT mode.
Click to expand...
Now, there's something that makes a lot of sense. Use KBXT and an AT keyboard to put an AT's controller into XT mode so you can hotswap an XT keyboard into the AT. :) :) :) And I thought I was bored! I'm beginning to feel better already. :)
 
I have an 83 key Model F, available, that needs the spring replaced under the Alt key. It works with the rig I made for it, though. It's Part No. 1503206, came with the 5150, and was made in 1984.
 
As the owner of a AT Model F, I can tell you it is a troublesome beast. And they are very hard to find! I was on the lookout for months before finding one.

They use foam between the top metal plate (which is black painted) and the bottom plate which is galvanised metal+pcb.

The top metal plate is likely to be rusty given these are very old now. And if you take it apart to fix the rusty plate, you are likely to find the foam in between falls to pieces. And then you have to replace the foam, which requires you to make a replacement.

Then you have to put it all back together, and hope it works! Often it can take multiple goes to get it right (read the links below).

Read about the processes here:

http://www.epiguru.com/2012/05/model-f-project-reassembly/

http://geekhack.org/index.php?topic=37753.0

The first link covers an AT model, the second a 122 key, but what you have to do is very similar.

If after reading about what you need to do, then wait your turn to find one :)

And it will make you a keyboard geek, so you should probably join geekhack.com!

If you want something AT sized and buckling spring and don't want the headache, get a Model M Spacesaver. They are expensive too, but the technology is simpler and easier to fix.

If you have money, just buy a Model M Spacesaver someone else has already restored - they do turn up on eBay.
 
Thanks for the info Grrr8 !!

Yeah, I know they are very hard to find. I'm currently using a model M #1391401 (very similar to the #1391406), 102-keys. It's large, probably not a Spacesaver (I will have go research the Spacesaver). It has a PS/2 connector, so an adapter is used.

The problem I'm having with it is after I boot up, I have to unplug then plug back in the keyboard, and then the scancodes are correct. If I don't do that, the function keys get messed up and I have to reboot to close some programs (like Norton Commander), and I get capital letters even though the caps lock is not on.

Anyway, seems to have fixed the problem. My AT is a model 239, before they could handle an enhanced keyboard. I have one 1501105 keyboard for my two earlier machines, a PC and an XT. I wanted to be authentic as possible.

Guess I'll start saving my $$$ for a newly refurbished 0225 !!

Greg
 
greg2002 said:
Yeah, I know they are very hard to find. I'm currently using a model M #1391401 (very similar to the #1391406), 102-keys. It's large, probably not a Spacesaver (I will have go research the Spacesaver). It has a PS/2 connector, so an adapter is used.
Click to expand...
Yes, the 1391406 is *not* a spacesaver. :) The spacesaver has 84 keys. If you find one it's probably gonna cost an arm and a leg. Ask Shadow Lord -- I think he's very knowledeable about these keyboards and their pricing.

The 1391401 keyboard does have a detachable cord, however. I have a NOS Model M cord with an AT connector if you're interested.
 
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