Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!linus!philabs!cmcl2!seismo!umcp-cs!cvl!umd5!louie
From: louie@umd5.UUCP (Louis Mamakos)
Newsgroups: net.micro.amiga
Subject: Memory/clock expansion for the Amiga (4/9 - clockset.doc)
Message-ID: <1018@umd5.UUCP>
Date: Wed, 11-Jun-86 16:08:10 EDT
Article-I.D.: umd5.1018
Posted: Wed Jun 11 16:08:10 1986
Date-Received: Sat, 14-Jun-86 05:00:34 EDT
Reply-To: louie@trantor.umd.edu (Louis Mamakos)
Organization: U of Md, CSC, College Park, Md
Lines: 23

The clock is set by using "clock" just like you would use "date" to set the
regular Amiga clock.  When you first build the board, the clock may gain or
loose a few seconds a day.  You can correct this by adjusting the variable
capacitor in the clock circuit.  The best way to do this requires patience.
Note the amount of error in a known amount of time, say a day or a week.
Make an adjustment of perhaps a quarter turn on the capacitor (remember the
direction). Wait this amount of time again.  Note the change in the error.
Now you can correct the capacitor by the proportional amount.  If the error
is worse, the capacitor must be turned in the opposite direction from the
first attempt.  If the error is of the opposite sense, then the first
adjustment overshot.  If a quarter turn is worth a second a day, then to
correct a second a week will require a one twentyeighth turn.  Since such
delicate adjustments are hard to make, you may need several tries.  You can
quit when the clock is sufficiently accurate for your needs.  Ultimately,
the clock can be adjusted for about one second a month error.  This may be
more trouble than you wish to take, since correcting the time is a one line
command.


-- 
Louis A. Mamakos WA3YMH   University of Maryland, Computer Science Center
 Internet: louie@trantor.umd.edu
 UUCP: {seismo!umcp-cs, ihnp4!rlgvax}!cvl!umd5!louie