Date: Mon, 7 Aug 1995 11:22:29 +0930 (CST) From: Michael Smith <msmith@atrad.adelaide.edu.au> To: tweten@frihet.com Cc: msmith@atrad.adelaide.edu.au, spaz@u.washington.edu, questions@freebsd.org Subject: Re: 115200 hangs my modem :-( Message-ID: <199508070152.LAA22094@genesis.atrad.adelaide.edu.au> In-Reply-To: <199508070105.SAA03006@tale.frihet.com> from "David E. Tweten" at Aug 6, 95 06:05:46 pm
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David E. Tweten stands accused of saying: > > It's possiuble to convince a 16550 to clock at ~115200Kbps, yes. It's a > > Really Bad Idea, but people persist in doing it. (If you want to know why, > > read the datasheet.) > > Okay. I have the datasheet (although 22 pages is a bit large for a "sheet") > and I've read it. The way I read it, 115200 Kbps with a 1.8432 MHz crystal > calls for a divisor of one, which is acceptable up to crystal frequencies up > to 4 MHz (section 8.3, paragraph 1, sentence 2). > > Care to provide any hints? Like page and paragraph numbers? MHA; I misremembered two things: The warning in 8.3 is actually for a divisor of _0_, and the 16550 divides to a 16x sampling clock, rather than having a fixed sampling clock and dividing it to produce a bit rate. On rereading, there shouldn't be anything wrong with 115200. > David E. Tweten | PGP Key fingerprint = | tweten@frihet.com -- ]] Mike Smith, Software Engineer msmith@atrad.adelaide.edu.au [[ ]] Genesis Software genesis@atrad.adelaide.edu.au [[ ]] High-speed data acquisition and [[ ]] realtime instrument control (ph/fax) +61-8-267-3039 [[ ]] My car has "demand start" - Terry Lambert [[
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