Freddie, Use Interrupt to detect low going START BIT. Wait 1/2 Bit period If BIT still low then start BIT is valid If valid, wait 1 BIT period and read data BIT (x 8) wait 1 final BIT period and read BIT. If high then STOP BIT is valid - Word is OK To improve reliability, you can sample quickly multiple times at sample points. ie. say sample 3 times at 8 times BIT rate and 2 out of the 3 samples indicate valid state. Regards David Huisman -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body