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Xref: sserve comp.os.linux.misc:29978 comp.os.386bsd.misc:4126 sci.electronics:84365 Newsgroups: comp.os.linux.misc,comp.os.386bsd.misc,sci.electronics Path: sserve!newshost.anu.edu.au!harbinger.cc.monash.edu.au!bunyip.cc.uq.oz.au!munnari.oz.au!spool.mu.edu!sdd.hp.com!saimiri.primate.wisc.edu!caen!math.ohio-state.edu!magnus.acs.ohio-state.edu!csn!slate!mbarkah From: mbarkah@slate.mines.colorado.edu (Ade Barkah) Subject: Re: 16550 detection Message-ID: <1994Nov18.082900.12223@slate.mines.colorado.edu> Date: Fri, 18 Nov 1994 08:29:00 GMT References: <CMETZ.94Oct30051603@itchy.inner.net> <MICHAELV.94Nov1215132@MindBender.HeadCandy.com> <TYTSO.94Nov2113942@dcl.mit.edu> <JKH.94Nov2210122@freefall.cdrom.com> <Cyp34w.MxC@bonkers.taronga.com> <3a8u29$mi@awfulhak.demon.co.uk> <CzF7qx.9yH@indirect.com> Organization: Colorado School of Mines X-Newsreader: TIN [version 1.2 PL1] Lines: 30 Barnacle Wes (wes@indirect.com) wrote: : Brian Somers (brian@awfulhak.demon.co.uk) wrote: : : Please inform someone who thought that bps was the same as baud of : : their ignorance.... : In the days of 2400 bps/Baud modems, they were. A 2400 bps modem : transmits and receives (transcieves? ;^) two tones, one means "0" : and the other "1". If you use *more tones*, you can encode more than : one bit in each state change. Actually, I don't even think for 2400 bps modem 1 baud==1 bps. If I remember, the 2400 bps modems already use quadrature amplitute modulation (qam) encoding, with 600 baud/s at 4 bits per baud. : The Trailblazer used 512 different tones, and a unique encoding : method called (if I remember correctly) trellis encoding, and 7 : state changes/sec, or Baud, to achieve ~20,000 bps throughput. I'm not familiar with Trailblazers (I'm assuming you're talking about PEP) but 7 baud/s seems pretty slow. Maybe you ment it the other way: the trellis encoding gives it 7 (or 8) bits per baud, running at 512 bauds/sec. This is still far short of 20 kbps. A more likely scenario would be 8 bits per baud at 2400 baud per second for a 19,200 bps throughput (or 16.8 kbps if using 7 bits per baud). -Ade Barkah -- Renaissance Knowledge Systems, Englewood, Colorado.