Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ncar!tank!eecae!abaa!esker
From: esker@abaa.uucp (Lawrence Esker)
Newsgroups: comp.sys.amiga
Subject: Re: New Agnus
Message-ID: <4710@abaa.UUCP>
Date: 10 Nov 89 20:05:33 GMT
References: <3707@nigel.udel.EDU> <127660@sun.Eng.Sun.COM> <3755@nigel.udel.EDU>
Reply-To: esker@abaa.UUCP (Lawrence Esker)
Organization: Allen Bradley
Lines: 29

In article <3755@nigel.udel.EDU> new@udel.edu (Darren New) writes:
>I think the original question was how to detect the presence
>of an "uninstalled" New Agnus. Obviously, if the New Agnus is
>properly installed then you will boot with more than 512K 
>of CHIP ram.  But what if the new agnus is in a machine that
>originally had the old agnus in it but had the old agnus pulled
>and the new agnus inserted without any other changes?  How does one
>detect that?    -- Darren

This is how I interpreted the original message.  I had sent a mail message but
it bounced and I since deleted the message.  (If someone can't post working
reply addresses, then they aren't woth my effort to respond more than once.)

Since there are many people not answering the original question, I will try
again.  The only way I know is to inspect the part number of the Agnus chip.
There should be a 4 digit number that (If I remember right) is 873x.  Where
x is

    0   Original NTSC agnus
    1   Original PAL agnus
    2   New Super Fat agnus, NTSC and PAL.

The board has jumpers to select the PAL or NTSC mode at powerup, inform the
agnus chip to use the extra 512 k, and change the memory from $C00000 to
$080000.
--
---------- Lawrence W. Esker ----------  Modern Amish: Thou shalt not need any
                                         computer that is not IBM compatible.
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