RPG Rotary Pulse Generator
Rotary Pulse Generators (RPGs), also known as rotary encoders, are a simple easy to use input device.
Rotary Pulse Generators (RPGs), also known as rotary encoders, are a simple easy to use input device similar to that of a potentiometer (pot) with a few subtle differences. First of all an RPG does not have a lower or upper mechanical bound, where as with a pot there is a clearly defined min and max to how far you can turn it. RPGs also commonly have a push button beneath the knob allowing for another user input without any additional space being used. While slightly more expensive than a pot, RPGs are much more versatile and still relatively inexpensive.
The RPG used to develop this Library is available from Sparkfun
See http://developer.mbed.org/users/canderson199/notebook/rotary-pulse-generator-library/ for more details.