I'm using PSP mode on a PIC to interface to a PC parallel port. In the PC application, I'm using BIOS interrupt 0x17 to send stuff to the PIC thru the parallel port. My BIOS book is real old (1991) and make no mention of bidirectional parallel ports. Is there a STANDARD BIOS call to read from a parallel port? Harold FCC Rules Online at http://hallikainen.com/FccRules Lighting control for theatre and television at http://www.dovesystems.com ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/tagj. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.