15 April 2010
You can learn more details about GKOS for Arduino here.
If you are planning to build a stand-alone system where a small but full-featured keyboard is needed, this simple solution could be useful for you.
With the 6 GKOS keys, directly connected to Arduino I/O pins, it is possible to type any text and enter most functions found on the PC keyboard (Alt, Ctrl, Tab...).
Other I/O pins can also be used.
There are sample sketches showing how to use the library. One sketch uses an LCD to display the text typed, one just indicates the keypad operation by the pin 13 LED on the Arduino board. The third sketch uses the IDE Serial Monitor to show the text typed.
The GKOS Alphabet.
Letters G, K, O, S and W require two keys, and they also function as modifiers (shifts) changing the characters on other keys.
Pressing all 6 keys down toggles between numbers and letters. You get backspace by pressing the 3 keys on the left, and space by pressing the 3 keys on the right. The full character set can be found here.