Software framework for demonstrating RF SOAP modul

Features
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- power handling (off, on, battery check)
- button handling
- rfm12 handling
- power saving
- UART (9600 baud, 8N1)

Hints
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- Leave clock fuses in factory setting (1 MHz internal clock (8 MHz, clockdiv activated)

Operation
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- Hold main button > 1 s (or connect USB to FT232, this will also power up the module)
- if battery voltage is sufficient modul will start (middle led flashing)
- with side buttons a value can be set between 1 and 3, indicated by the LEDs
- with main button the value will be sent over radio
- when value is received, the appropriate LED will flash and value is sent over serial interface
- Hold mainbutton > 1 s to switch of