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From: Jay Miller (jnmiller, cryptofreak dot org) Date: 2001.03.08 - 19.15 MST
X-Mailer: Mutt 1.2.5i So, by reading around a bit I've found out a few important things: * We're dealing with 'phase modulation'. I'm retarded for calling the difference in the wave 'frequency' - phase is changing, not freq. Anyway, this is a very common method and in order to use it, the serial connection needs a constant (control) clock signal at all times to either negate or double the signal that we were given. The moral here is that PM is not used with asynchronous (start-stop) serial communication. * Synchronous transmission works by sending large blocks of data in a continuous stream of (usually) 2000-4000 characters. These characters are bordered by 'STX' and 'ETX' symbols (sometimes two or three) rather than start/stop bits. Here's some good references: http://wheelie.tees.ac.uk/users/a.clements/Async/async.htm http://www.rad.com/networks/1994/modems/modem.htm http://www.microsoft.com/TechNet/HW/async232.asp So, ah, this could be harder yet. <sigh> -- Jay Miller ICQ: 32123421 | YM: ladenedge | http://www.cryptofreak.org PGP: 0xedc9bb8d | 41a6428c 46abd36b 6b259b68 8a28ca4c edc9bb8c -- This is the mod-chal mailing list. To unsubscribe, email majordomo, cryptofreak dot org with message body 'unsubscribe mod-chal'. Or, for more information, visit http://www.cryptofreak.org/.
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