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geekhack Community => Keyboards => Topic started by: Jerryno on Wed, 29 November 2017, 15:38:35

Title: T570 keyboard to USB conversion
Post by: Jerryno on Wed, 29 November 2017, 15:38:35
Hi,

I would like an external full keyboard with Trackpoint and backlit, but it seems these are impossible to get. The only solution it seems is to get a T570 replacement keyboard and convert it into USB, then make a nice wooden housing for it:

(https://i.ebayimg.com/images/g/kXEAAOSw-wJZ7bC2/s-l500.jpg)

There are two ribbons coming out of this keyboard, one is the key matrix and the other is the PS/2 trackpoint. I have the capability of soldering smd parts and I have read these articles:

http://www.instructables.com/id/A-Better-ThinkPad-USB-Keyboard-Adapter/
http://www.instructables.com/id/Make-a-ThinkPad-keyboard-USB-adapter-with-Arduino/
https://www.tindie.com/products/rampadc/arduino-thinkpad-usb-keyboard-adapter/

Would like to make a similar board, maybe even with Bluetooth to go wireless, but I don't want to complicate things on the beginning (battery management charging etc.). USB will do for starters.

I am familiar with how keyboards are wired and I can do arduino programming, but I didn't done any keyboard yet and would like to avoid making too many prototypes. So I turn to you for advise:

- would it be better to cannibalize some existing old keyboard or is it better to hook everything to some I2C Keypad Scan IC connected to teensy? I would like to have all keys functioning. Do you have some Keypad Scan chip to recommend?
- I have no idea how to connect that PS/2 Trackpoint with buttons, had no luck finding any reference. I would greatly appreciate some help with this. If nothing I will reverse-engineer how it is wired from the links above, but I would like to spare myself this work.
- I am unsure which wires handle the backlight, couldn't find any datasheet for the keyboard. Any chance it uses the same connector and scheme as some older variant or one without the numpad?

I appreciate any help, this info is hard to find. If no one knows, I will try-and-error this. If successful I would post this here as open hardware design, but can't promise anything yet. I am still noob in this.



Title: Re: T570 keyboard to USB conversion
Post by: Techno Trousers on Wed, 29 November 2017, 20:13:29
Is backlighting really so important that you'd use a crappy laptop keyboard? What about the Unicomp EnduraPro?
Title: Re: T570 keyboard to USB conversion
Post by: C5Allroad on Fri, 01 December 2017, 10:49:59
There was a keyboard floating around on r/thinkpad that was a 60% and had trackpoint.  Although I'm not sure that it's as good as trackpoint.

I haven't seen anything fullsize with trackpoint. But after using my T470 for like 2 months I'd love a mechanical keyboard with trackpoint.

As far as backlighting goes.I rarely use mine, there's a lot of light bleed around the caps making it really bright and not just the letters being lit up but around the keys.


[edit] I found the keyboard
https://www.massdrop.com/buy/tex-yoda


Is backlighting really so important that you'd use a crappy laptop keyboard? What about the Unicomp EnduraPro?

To be completely fair, when it comes to laptop keyboards thinkpads aren't that bad. They're pretty damn good for a laptop.
Title: Re: T570 keyboard to USB conversion
Post by: Jerryno on Sat, 02 December 2017, 13:32:57
Imho thinkpad laptop keyboards are very good, if not the best. But that Unicomp EnduraPro has a very poor build quality. I'd like a slim profile keyboard because it is easier to transport. That's why I am also thinking about that Bluetooth conversion later, for portability reasons..

Yep seen the TEX Yoda. It is not that bad, if it was with numpad I would change the switches and keycaps to support backlight do some wiring and call it a day. It is DIY friendly keyboard. There is also this 60% Thinkpad keyboard https://www.amazon.com/ThinkPad-Compact-Bluetooth-Keyboard-TrackPoint/dp/B00C32FWJC with BT which would be the dream, but no backlit and no numpad.
 
Unfortunately I am also not a fan of light-bleed around keys, hopefully I'll be able to modify that with black nail polish.

I found another great resource: https://flashandrc.wordpress.com/category/thinkpad-keyboard/. This guy is probably the one I need to learn from. T570 replacement keyboard is on the way. I got also this: http://wiki.epalsite.com/index.php?title=Mega2560_Pro_Mini as it should have all the pins I need for research. This will also be handy if that trackpoint is just a sensor with analog output out and has no PS/2 mouse circuitry on the keyboard. In the end I am planning to switch that for some Keypad Scan chip.

I don't know how soon I will have any results (if any:), but probably after holidays as that will give me some time to work on this.
Title: Re: T570 keyboard to USB conversion
Post by: dando on Fri, 04 May 2018, 17:03:29
Hi, any news regarding this interesting and quite useful project?
Title: Re: T570 keyboard to USB conversion
Post by: CarloS83 on Sat, 12 May 2018, 04:41:20
Hi to everyone, i'm a new member of geeekhack.
I'm very interested about this topic, i love thinkpd keyboard (i have a thinkpad x1 carbon 3rd generation).
I think that this controller http://sprintek.com/products/sk5102.aspx could be the perfect one for this project.
It has a programmable 8X20 matrix, an integrated ps/2 in, led backlight controller and a rotary encoder for an additional volume knob.
Now we need the pinout of the ribbon cable, the matrix of the keyboard and a schematics for backlight led.
Title: Re: T570 keyboard to USB conversion
Post by: ptykozoon on Fri, 18 May 2018, 17:26:43
why backlit doe