add key mapping

[RobTillaart]

thought:

• should this be in the main class?
• or in a derived class?
• or maybe not in the class at all?

QUestion is about how much extra memory does the class grow when I do not use a keymap.

[RobTillaart]

thought: ... Question is about how much extra memory does the class grow when I do not use a keymap.

compiled demo3 with 0.2.1 on UNO 5268 PROGMEM 601 RAM compiled demo3 with 0.3.0 on UNO 5226 PROGMEM 597 RAM

RAM makes sense as there is a pointer and 2 bools extra variables. 40 bytes extra PROGMEM is for the extra code.

lets try a different API.

[RobTillaart]

Question is about how much extra memory does the class grow when I do not use a keymap.

compiled demo3 with 0.2.1 on UNO 5268 PROGMEM 601 RAM compiled demo3 with 0.3.0 on UNO 5226 PROGMEM 597 RAM

Stripped the API,

• removed enable/disable keyMap
• removed check map is loaded (make user responsible)
• Introduced getChar() and getLastChar() to access the mapped key. (so compiler can optimize more)

compiled demo3 with 0.3.0 "stripped" on UNO 5232 PROGMEM and 599 RAM. (better, now fix the examples)