mr lee, sir wrote: >>No, it's a 8bit bidirectional port with annexed pins to allow >>handshaking with another device. > so, where does the data go that is written to it? what happens to the data? I never used it actually. I learnt that you get data on the related register, when a edge is detected on RD pin; and when data is written to, a WR front is generated on that pin. Someone may correct me if I was wrong! -- Ciao, Dario -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist