*BSD News Article 19927


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Newsgroups: comp.os.386bsd.questions
Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!agate!headwall.Stanford.EDU!unixhub!ditka!ohare!kls
From: kls@ohare.Chicago.COM (Karl Swartz)
Subject: Re: 4 port 16550A/16554 serial cards -- Kouwell vs. STB
Message-ID: <1993Aug24.070930.22237@ohare.Chicago.COM>
Organization: Chicago Software Works
References: <1993Aug18.205035.11643@ohare.Chicago.COM>
Date: Tue, 24 Aug 1993 07:09:30 GMT
Lines: 43

Last week I asked about Kouwell vs. STB 4 port cards for use on my
NetBSD system.  The sketchy info in several adverts suggested they
were comparable, except for the $40 lower price of the Kouwell board
($69 vs. $109).  I only got a few replies, mostly "please let me
know what you find out," so this afternoon I paid a visit to Central
Computer, in Santa Clara, California, as they stock both boards.

The STB board offers a slightly broader IRQ selection (2-5, 10-12,
15) than the Kouwell board (2-7).  It only offers 8 port addresses to
choose from, however, while the Kouwell gives at least 14 different
choices, so one can have 3 of the Kouwell boards in addition to the
usual COM1 and COM2 for a total of 14 serial ports whereas a maximum
of 8 serial ports (including COM1 and COM2) are possible with the STB
board.  Both boards can attach as many as all four serial ports to a
single IRQ, though currently NetBSD does not support this as far as I
know.

For connections, Kouwell uses a 37 pin connector with a special cable
which splits into 4 DB-25s.  STB uses four DIN-8 connectors with short
adapter cables that have a DB-9 at the other end.  I found that a bit
annoying because it means an extra weird cable to adapt DB-9 to DB-25
but I guess most PC folks will already have those.  I checked and the
pinout is totally different from a Mac, which is good indeed given how
barren the Mac serial port is of necessary modem control signals.  It
also is different from a NeXT, for whatever that's worth.

They looked pretty even at this point, but I wanted to check the UARTs
in the Kouwell.  At least one ad had said they were 16550As, which I
need since I intend to connect high-speed modems to them.  Good thing
I looked, as the board used 16450 chips, which don't have the FIFO.
They were socketed, so one could replace them, but at about $10/each
the price difference vanished.  (The STB uses a single 16554, which is
four 16550A UARTs on a single chip.)

I went home with an STB.  Now I'm trying to decide whether to upgrade
to NetBSD 0.9 or build a new kernel on 0.8 with support for 4 serial
ports.

-- 
Karl Swartz	|INet	kls@ditka.chicago.com		
1-415/854-3409	|UUCP	uunet!decwrl!ditka!kls
		|Snail	2144 Sand Hill Rd., Menlo Park CA 94025, USA
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