Hi, At present, I am studying on a Simulation Module of Intel 386DX. Is there anyone who also do such research? I am puzzled by the PTU(protect test unit), which I think is not neccesary, :P How do you think about it? I am glad to hear from you. yours, leyuanniao -- To unsubscribe from cores mailing list please visit http://www.opencores.org/mailinglists.shtml