Hello all. New guy here... The old Commodore 64 (and others??) used an asynchronous floppy disk drive. I don't remember all the details but I remember that it used a certain number of characters in a certain sequence that would not be possible in a data sequence. This was how it determined the beginning of a track. This may not be entirely relevant because the speed was fixed but there may be some parts of the algorithm which may be pertinent. Bennett -----Original Message----- From: pic microcontroller discussion list [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Bob Ammerman Sent: Tuesday, July 11, 2000 8:46 PM To: PICLIST@MITVMA.MIT.EDU Subject: Re: [EE]: RS232 error This only works if the start bit is followed by the opposite line state for a little while. Actually, you would not be restricted to a single bit per word: The line is idle (say a 0 on the input). Send a start bit (a 1) for time N. Send a dummy bit (a 0) for time f(N), where 'f' is a function of N. For example f(N) = N or f(N) = N/2. Send a group of data bits (1 or 0) for g(N) time each, where 'g' is another function of N. Return the line to idle. Bob Ammerman RAm Systems (contract developer of high performance, high function low-level software) ----- Original Message ----- From: James Cameron To: Sent: Tuesday, July 11, 2000 9:37 PM Subject: Re: [EE]: RS232 error > Hrm, this implies that to communicate without regard to clock accuracy > one could reduce to one bit per word, and then the receiver could > determine the rate by measuring a start bit time ... is there a name > for this form of protocol? > > -- > James Cameron mailto:quozl@us.netrek.org http://quozl.netrek.org/ > > -- > http://www.piclist.com hint: The PICList is archived three different > ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu