> -----Original Message----- > From: Duilio Foschi [SMTP:foschid@SUMMER.ETRURIA.NET] > Sent: Thursday, 16 September 1999 17:15 > To: PICLIST@MITVMA.MIT.EDU > Subject: transferring data > > can PICs talk transfer data from one to another using one of their pins ? > (w/o a UART, I mean). > > Can 8051 uPs do the same ? > > Thank you > > Duilio Foschi > 1 pin on each for one way transfer with self syncing, 2 pins on each for two way transfer with self syncing, 3 pins on each if a clocking or comms enable signal is used to synchronize all comms. Self syncing usually involves sending a pattern in front of the data to allow the receiver to do its housekeeping (break out of whatever other routine it was doing) and watch for the start-of-data pattern. 6 x ASCII '01010101' is a good door bell pattern to use, followed by a null '00000000' and char 255 '11111111' giving a big 'ding-dong' wake up followed by an unmistakable 8 x 0 and 8 x 1 to identify the start of data - 0101010101010101010101010101010101010101010101010000000011111111 Bye.