Alan Parekh's latest creation is a clock made from wooden gears.
Parekh says on Hacked Gadgets:
"The clock...consists of a bunch of wooden gears, a PIC microcontroller and a stepper motor. The heart of the clock is a PIC 16f628A microcontroller. This microcontroller has an internal oscillator however an external 20MHz crystal oscillator is being used since it will have to accurately keep track of time for weeks and months. The microcontroller is interfaced to two buttons and one motor...
To achieve the correct timing the 9 tooth motor gear is advanced 4 steps every 9 seconds. By moving 4 steps at a time the motor routines can be simple since the motor is always at rest with the same coil energized."