What are the capacitor values needed for the 5V power supply?
The parallel port adapter requires a 5V power supply to power the reader and the buffer chip. We create this by using a 9V batter and a 7805 voltage regulator. Technically, you do not need capacitors as shown. However the capacitors stabilize the 5V, making dying batteries work longer, and allowing voltage picky readers to work. Since we are dealing with digital instead of analog circuits, the exact value of these capacitors doesn’t really matter. Capacitors on the order of 1uF or 0.1uF should work just fine, though I imagine larger ones would work as well.
