Centronics interface

Lots of people seem to think that computers show the results of their number crunching activities on screens only. The highly educational circuit described here dernonstrates that a standard PC interface such as the parallel printer port may be used for applications which are off the beaten track. It may be used, for example, to drive external circuits. After your experiments, the circuit may be used as a permanently installed data exchange monitor in the PC-to-printer link.