hoskins@iccgcc.decnet.ab.com (04/11/91)
Has anybody heard of an algorithm called "Auto Baud"? What this is, if I understand correctly, is a method for a initializing a modem or serial port by trying to sync up to a known incoming data stream (all the same character, I think) and guessing at the baud rate, parity, etc. until the data stream is received. If anyone knows where I could find an article describing the algorithm, or maybe even source code, I would be greatly appreciative. Steve Hoskins Allen Bradley, Motion Control Division
root@zswamp.uucp (Geoffrey Welsh) (04/12/91)
>From: hoskins@iccgcc.decnet.ab.com >Has anybody heard of an algorithm called "Auto Baud"? What >this is, if I >understand correctly, is a method for a initializing a modem >or serial >port by trying to sync up to a known incoming data stream >(all the same >character, I think) and guessing at the baud rate, parity, >etc. until the data stream is received. I've seen some software that picks a baud rate and waits; if a framing error occurrs, it switches. I would think that one should start at a high baud rate and hope that incoming data words would be long enough to cause framing errors until the correct word size is chosen (though careful selection of data might conceivably prevent this). The incoming caller may send BREAK signals to force a change of baud rate. Of course, this doesn't address the possibility of line noise causing an error and triggering a switch *from* the correct baud rate! -- UUCP: watmath!xenitec!zswamp!root | 602-66 Mooregate Crescent Internet: root@zswamp.fidonet.org | Kitchener, Ontario FidoNet: SYSOP, 1:221/171 | N2M 5E6 CANADA Data: (519) 742-8939 | (519) 741-9553 The mile is traversed not by a single leap, but by a procession of coherent steps; those who insist on making the trip in a single element will be failing long after you and I have discovered new worlds. -- me