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From: waltrip@capd.jhuapl.edu
Newsgroups: comp.sys.next
Subject: Re: Is there an 8+ serial port mux for NeXT cubes available?
Message-ID: <1991May3.144622.1@capd.jhuapl.edu>
Date: 3 May 91 19:46:22 GMT
References: <9104240831.AA01164@lhs.woodside.ca.us> <573@rosie.NeXT.COM> <1991Apr26.023505.32391@mp.cs.niu.edu> <1991May2.214100.13070@zardoz.cpd.com>
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In article <1991May2.214100.13070@zardoz.cpd.com>, neil@uninet.cpd.com (Neil 
Gorsuch) writes:
	[...material deleted...]
> The way that our stuff works, we only incur interupts on each
> block of characters, and the vast majority of characters traveling on
> a serial port come as blocks of output characters from application
> programs.
	I'd be interested in more details on how this works.  This sounds a bit
	like you can't do raw (character at a time) I/O...but I doubt that's
	true.  Comment?

	[...material deleted...]
> ...compare our price to an ethernet serial box.  The last
> time I looked, most of them were in the $2,000 to $3,000 range.
	I believe they may be available in the $1,500 range these days.
	BTW, I believe the overhead issue is of some
	significance with regard to Ethernet terminal servers...both in terms
	of Ethernet traffic and use of ptys.  TCP/IP based terminal servers
	tend to introduce a somewhat disproportionate Ethernet load...and don't
	they generally just make a telnet connection to the host, using a pty
	(and a socket?) in the process?

c.f.waltrip

Internet:  <waltrip@capsrv.jhuapl.edu>

Opinions expressed are my own.