I also built a MiniPOV, which is a kit from Adafruit. The major part of the minipov is the ATtiny2313, which is a microcontroller chip. It is customized by the AVRDUDE, which is a command line program. The LED lights are controlled by the chip and coding. 0 is off and 1 is on. There is a frequency controlled by the chip that allows you to see an image through the flashing of the lights. A minor part of the minipov is the diode, which limits the flow of current in one direction.