This is the basic interface I used as part of my Computerized Room project. This is the parallel interface only. The 8 bit input card can be found, along with the rest of the project, at Computerize Your Room .This interface, as well as the other two interfaces, came from the book The Robot Builders Bonanza, by Gordan McComb. This interface is also useful for controlling small robots, etc. It is cheap and fairly easy to build, although you should not attempt this project unless you have prior experience with electronics
Part Total Qty. Description Substitutions
U1, U2, U3 3 74LS367 Buffer IC 74367, 74HC367
MISC 1 Case, Wire, Sockests, 18 Pin Socket (For Output), 25 Pin Connector (For Parallel Port), Ribben Cable
The interface is built on a piece of universal solder board due to the large number of wires that must cross. It is also much easier to fix mistakes then on a PC board.A 25 pin crimp connector is used to connect it to the parallel port. 26 conductor ribben cable was used to link the connector to the board
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