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Path: utzoo!watmath!clyde!rutgers!uwvax!husc6!mit-eddie!genrad!decvax!tektronix!reed!kamath
From: kamath@reed.UUCP
Newsgroups: comp.sys.apple
Subject: Re: Interrupts on the //c
Message-ID: <5091@reed.UUCP>
Date: Sat, 24-Jan-87 22:11:56 EST
Article-I.D.: reed.5091
Posted: Sat Jan 24 22:11:56 1987
Date-Received: Mon, 26-Jan-87 01:44:22 EST
References: <220@cacilj.UUCP>
Reply-To: kamath@reed.UUCP (Sean Kamath)
Distribution: world
Organization: Reed College, Portland, OR
Lines: 50
Keywords: Is it me or what?

In article <220@cacilj.UUCP> paul@cacilj.UUCP (Paul Close) writes:
>No problem.  The only problem is that even with an interrupt-driven driver,
>the poor //c can't go much faster than 1200 baud!!!  (i.e. forget 2400).  I
>
>	Paul Close
>	(...!{crash, gould9}!cacilj!paul)


Well, I don't know, but I'd be willing to bet that you have an older //c
that had timing problems with the ports above 1200 baud.  Apple had a
policy of exchanging motherbaords on //cs that had this problem if you
brought in the hardware (which had to include your non-apple brand
modem.)  I don't know if it's still in effect...let me check.  Let me
qualify that. 

Serial Port Solutions - ODL299 Announced April 85.

"blah blah blah"
You can exchange a login board if the following conditions are met:

 - Customer shows proof of purchase of a non-apple modem; or,
 - THe problem can be duplicated with another serial device.

The Apple IIc serial port revision can be indentified by a silver
component located at location UC7 instead of a black LS161 integrated
circuit.

so, you may very well have a problem board.  I don't know the exact
serial numbers off hand, but I bet that is the problem.


________________________________________________________________________________

Sean Kamath

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