Benny, The paper tape reader is not a servo system but just a way of loading the nc program.
Paramax, I looked into this a while ago, commonly known as a BTR or behind-the-tape-reader.
It depends on some degree how your machine electronics handle the information coming out of the reader, I did however make a parallel to serial interface for converting the tapes into a RS232 serial port. The reader essentially is a paralled read (8 bit + 1 bit for the sprocket hole) The sprocket hole is read also and is used for clocking the 8 bit data. it should be possible to emulate the reader itself by using a printer port possibly. If you have any ideas let me know.
Al
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.