This small module is used to control a set of lights on a model boat (Milford Star).
An AVR ATtiny24 microcontroller decodes a standard RC proportional input signal (pulse length encoded value) and switches lights accordingly, from off to all 6 lights on. The AVR is powered through the RC receiver (5V), the lights have their own power source (unregulated 6V on the boat). Switching is done with small MOS-FETs, each capable of handling up to about 500mA.
The AVR is programmed using the standard Atmel tools in C, using up about 1.2kB code space (of 2kB available) with a range of filtering and failsafe code included. Calibration information is stored in the on-chip EEPROM section.