Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!rice!sun-spots-request
From: henry@zoo.toronto.edu
Newsgroups: comp.sys.sun
Subject: Re: Serial port speed
Keywords: Miscellaneous
Message-ID: <10199@brazos.Rice.edu>
Date: 24 Jul 90 16:58:32 GMT
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X-Sun-Spots-Digest: Volume 9, Issue 277, message 14
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>With our SCSI based serial port expander, baud rates can be any arbitrary
>value up to almost 150K baud.  And that limit is there only because the
>particular RS232 drivers that it uses starts to produce triangle waves
>rather than square waves 8-).

If one is being picky, one should note that that speeds beyond about 38400
are violations of the RS232C spec, which sets a limit on the speed of the
transitions from positive to negative.  Even 38400 is marginal, actually.
Old RS232C drivers seldom implement the transition-rate-limiting, though,
and with short cables and forgiving conditions the high rates generally
will work.

                                         Henry Spencer at U of Toronto Zoology
                                          henry@zoo.toronto.edu   utzoo!henry