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Modding a Thinkpad Keyboard for External Use?
Rinisari asks: "I've recently acquired a working keyboard from a IBM Thinkpad. It has ~87 keys, mousestick with left, right, and rocker buttons, and five other buttons: IBM, volume up/down/mute, and a power button (part number 08K4785). I want to make an interface cable, preferably USB but PS/2 will suffice, to be able to use this on my desktop. Has anyone ever tried something like this?"
Have you checked if this thing has a keyboard controller chip built in? Normal PC keyboards have their own logic but laptop keyboards AFAIK don't, the logic may be somewhere on the laptop's mainboard.
Are you aware you can buy keyboards from IBM that are pretty close to what you want? In fact, this is slightly cooler, just because it comes with the number-pad, too..
D C= 461017
D C= 170470
http://www.cdw.com/shop/products/default.aspx?E
Or, if you really want the number-pad-less version, try this:
http://www.cdw.com/shop/products/default.aspx?E
Don Head
UNIX/Linux Administrator
Available from IBM:
88-Key Space Saver II Keyboard (Business Black)
Link is to the danish model.
Granted, you already have a keyboard and thus it's free. But I've got one of these (blue lights, black frame) and it's wonderful. Just like a notebook keyboard - perfect for coding: http://www.thinkgeek.com/computing/input/keyboards /5c3f/
I spent some time pondering something similar while putting together a home-made vertical split keyboard.
Didn't come across anything with IBM's name on it, but among the salvage laptop keyboards that I found in parts stores, none were easy to turn into a working keyboard. They not only lacked a controller, but they seemed to have entirely unique path layouts, making the prospect of finding a suitable ready-built controller unlikely. That's based solely on the three I explored - perhaps there are standards among some manufacturers.
The only suitable solution I could see was to cut every single circuit path on the keyboard and then wire them up *by hand* to a keyboard controller ripped out of a desktop keyboard, after carefully tracing out every path from the original desktop keyboard. Needless to say, it didn't seem worth the time required. But, with a DMM, a dozen dremel cutting disks, a half pound of solder, a weekend, and a whole lot of patience you could do it.
If you're willing to spend 100 bucks or more, you can find programmable controllers, and you might get lucky and find one compatible with the existing laptop keyboard. But, for that price, you can probably buy a keyboard to suit your needs right off the shelf.
If by some chance you find a nifty solution, please post it here. I'd love to see it.
I guess the silliest answer would be to attach it to an ibm laptop and write a program to mimic a keyboard on the usb port. (I suspect you'd run into latency problems - but it could be fun just for the shear absurdity of it.)
Just put it up on eBay and let it go. Someone will want it for spare parts. That's all it's really good for; laptop keyboards are very nonstandard and the odds are very good that you won't ever figure it out. This is a project involving large amounts of reverse engineering, development of custom circuitry, and microcontroller programming.
...
Here kid, here's 5 bucks, go get yourself a real keyboard.
In order to pull this off, you will need to figure out how the keyboard's matrix is set up, then hook it up properly to a microcontroller, and then program said microcontroller to work with PS/2 (forget USB). Simply put no easy task. And then there's the trackpoint. With that, you will have to find a microcontroller with analog inputs, and figure out how the thing behaves electrically. Just give it up and buy a new keyboard. This thing is a task only for someone who knows a lot about EE, and has the time to do it.
Mewyn Dy'ner
Check out the 28L3644, but beware of sticker shock. If it's the compact keyboard idea that attracts you, check out any of the Happy Hacker keyboards, which used to be at www.pfuca.com but now appears to be dead.
Here's the US link. It's surprisingly expensive, compared to their other keyboards.. ($155).
It's likely wired so that each key generates an X/Y position on the ribbon cable, so it won't be useful by itself.
:-)
However, combining it with a project like this might be a possibility. I hope you like soldering (I do!
If you could be told what you can see or read, then it follows that you could be told what to say or think - BoC
Why not get A keyboard for $3.59 instead.
If you're really intent on doing this (and I don't recommend it; just buy one of the previously posted products), then I recommend asking IBM first for specs. You might find a tech or engineer who's willing to release them to you. Then, you'll probably want to learn some stuff about PIC chips. Take a look around at the numerous one-handed keyboards and whatnot for ideas. There are a lot of people who have done similar projects.
If the answer to that is "yes", then be prepared for a possible long haul. If you have never done this sort of reverse engineer, prepare for a very steep learning curve. Finally, if you have never wielded a soldering iron (though why you would contemplate this sort of project if you haven't is beyond me - it isn't a beginner's project), forget it.
Ok, with that out of the way - take a very good look at the keyboard. If you have to, remove the backplate (if it has one, and you can without damaging or disabling anything - sometimes this is impossible to know before doing it - if in doubt, don't do it). See if anywhere on the keyboard is a controller chip/circuit. If there is, write down all the numbers/info you can about each part, and about the board in general. Find out assembly numbers, revision numbers, part number. Finally, write down the part number/rev/version/assembly numbers for the keyboard itself.
If you didn't see any circuitry (though I would expect maybe some for the trackmouse thingie - maybe not), then you are in luck - it is a keyboard matrix. Now, all you have to do is figure out the matrix.
If it is such a keyboard, the best way is to look up on DigiKey the kind of connector you need for the keyboard ribbon cable (as it is likely to be a simple flexible cable with little or no connector). If you know what the connector looked like on the laptop, it would help. Basically, you are going to need to take some mesurements of the cable/connector and such, and try to find the proper DigiKey part. You may need to take some pics and get in contact with someone at DigiKey for info regarding this.
Regardless of whether it is such a keyboard or not - have you tried contacting IBM and asking them about it? Don't send you email to sales or whatnot - be polite in the email, state you have purchased the item used (or whatever), and are interested in researching the feasibility of using the device in a custom application. State that you are an electronics hobbyist, and that you are looking for pinout information for the keyboard. Ask to be forwarded to an engineer. Go a couple of rounds of email with them (don't be discouraged - but don't get angry, either - you will likely get exasperated easily) - sometimes if you are persistent it pays off. They might actually outsource the keyboards from a foreign manufacturer. It gets tricky if it goes that direction (because of language barriers), but it isn't impossible. Hopefully they can give you an email address.
If they do tell you they outsource from a foreign manufacturer, politely ask if they would refer to you who the manufacturer is - likely it will be an asian source. With that in name in hand, you might try googling on it, or checking out AsianSources.com (I think that is right). Basically, you are going to lead yourself down a strange and difficult path, but not an impossible one.
Hopefully, you will get someone on this end that will know what you are trying to do, and won't try to sell you another product.
Once you determine (however) what kind of interface you have (ie, matrix or on-board controller mediated), and once you figure out its layout (the purpose of finding the proper connector from DigiKey is so you can build the interface and hook it up to experiment easily), you can then work on the interface. You can either hook it up to the standard keyboard connector or USB - USB is more difficult, but it has become easier lately for hobbyists (check out recent back issues of Nuts and Volts magazine for info on USB interfacing). Basically, you are going to need a micro-controller of some sort in between the keyboard and the interface, to translate what comes from the keyboard into what your interface is expecting. I would use either a PIC of some sort or if you want easier development, a BASIC Stamp (essentially a PIC with memory and custom software - there are clones available as well). I suppose you could go with an Atmel uController, but it might be overkill. A simple PIC wo
Reason is the Path to God - Anon