Can anyone point me toward the circuit diagram including source code for an add-on circuit I can attach to the PC-AT keyboard line (in parallel) and which enables me to send key codes to the PC on detection of some input to the PIC? I need to simulate that the user presses some F-key on the keyboard when an external switch closure is detected. Bo Berglund PaddelvŠgen 10 17545 JŠrfŠlla Sweden tel: +46-8-580 15304 fax: +46-8-584 00 281 e-mail: bo.berglund@telia.com PGP: My public key is available at the following locations: Idap://certserver.pgp.com http://pgpkeys.mit.edu:11371