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From: neil@cpd.com (Neil Gorsuch)
Newsgroups: comp.dcom.modems
Subject: Re: Suns and Microcom modems at 38.4kbaud (is two way talk possible?)
Message-ID: <1989Nov20.093623.26018@cpd.com>
Date: 20 Nov 89 09:36:23 GMT
References: <6205@tank.uchicago.edu>
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Reply-To: neil@uninet.UUCP (Neil Gorsuch)
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Organization: Custom Product Design, Inc., Santa Ana, CA, USA
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In article <6205@tank.uchicago.edu> brian@tank.uchicago.edu (Brian Yanny) writes:
>I'm trying to get two Suns (either OS3.5 or OS4.0.3)
>talking to each other at 38.4kbaud using two Microcom QX/V.32c
>data compression modems.  The phone connection is at 9600 baud
>but the serial ports are at 38.4k to handle the compressed
>data.   The Suns are set in "TANDEM | RAW" mode or "TANDEM|CBREAK".
>TANDEM is Suns/Unix's port setting which means "Watch the input buffer,
>when nearly full send a XOFF, then send a XON when empty".
>RAW means receive all characters as is,
>CBREAK receives all characters and will stop/start on XOFF/XON.
>The modems are set to bi-directional XON/XOFF flow control.
>The modems support hardware RTS/CTS flow control, but Sun OS3.5
>does not and Sun OS4.0.3 only supports it in one direction.
>That is, if the modem drops the CTS line, the Sun stops sending,
>but there is no hardware flow control equivalent of "TANDEM", that is,
>you can't drop the RTS line when you input buffer gets too full.

The following is a biased suggestion 8-).  If you use our new
serial/SCSI interface, you can use full RTS/CTS/DSR/DTR/XON/XOFF
throttling in any combination while using the standard tty drivers
supplied with the Sun's.  Works with any SCSI equipped Sun.

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