Does anyone have details on the signals used in the (old) Dataproducts printer inteface? Basically I know it uses differential signals - otherwise similar to centronics - but I would like details. I have the Pinout: http://www.hardwarebook.net/connector/parallel/dataproductsdsub50.html I would like a description of "Demand" signal and the polarity of "Strobe" and "OnLine" I would like to know the levels (I presume TTL) If anyone can help me out, perhaps I can respond in kind by giving them the final result - a circuit for a Centronics-->Dataproducts interface. steve(a)airborn.com.au