[Gta04-owner] Keyboard for GTA04

Dr. H. Nikolaus Schaller hns at goldelico.com
Thu Mar 15 12:57:23 CET 2012

During the "Openmoko Stammtisch Munich" yesterday, we
have once again discussed options to build a special GTA04 keyboard.

And now I think we have found a way to really square the
circle. The square being functionality and the circle being

The idea is to use:
* off-the shelf pushbutons (Panasonic has some nice and very
   flat SMD buttons readily available at DigiKey)
* a Shapeways made custom case
* a not very sophisticated PCB with the buttons, a Bluetooth
   HCI module [1], a small LiIon battery and a microcontroller scanning
   the keyboard and supporting USB charging

Now comes the key idea: having a shapeways printed case makes
it possible to think about a keyboard built into a replacement battery
cover. It makes it a little thicker than normal, but you can detach it
and use it as a keyboard.

A first cost estimate:
* buttons: 25 ct each i.e. 16 EUR @ 64 keys
* case: 20 EUR
* bluetooth module: 20 EUR
* PCB + MCU: 20 EUR
* Battery, production etc.

So it should be possible to build such a beast at less than 100 EUR
(where we are back at the financial issues we generally have).

And, it needs people working on it.

Tasks will be to choose a HCI capable bluetooth module
and a MCU, write software (firmware), work on the schematics
develop 3D data for a Shapeways case.

Who would be interested (and has time and skills to contribute) to join
a team that starts working on such a project?


[1]: something like http://www.sparkfun.com/products/10823

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