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From: craig.treleaven@canremote.uucp (CRAIG TRELEAVEN)
Newsgroups: comp.sys.mac.programmer
Subject: TN261-68030 CACHES
Message-ID: <743e4cc3bfc72730fc24@canremote.uucp>
Date: 2 Nov 90 01:55:00 GMT
Organization: Canada Remote Systems Limited, Mississauga, ON, Canada
Lines: 20

UN:
   Tech Note 261 describes how to turn on and off the instruction
and data caches on the 68030.  And it works fine on a 68030.  But
I have two questions:

   1) The TN says: "make sure that the _HWPriv ($198) trap is
implemented, or your program will crash."  And yes indeed, it does
crash on a 68000.  But HOW does one check to see if a trap is
implemented?  I've looked at _NGetTrapAddress but it seems to
blithely return an address no matter what trap number you feed it.
Am I missing somethine obvious?

   2) What happens on a 68020 (or a 68040, for that matter)?  Does
the _HWPriv trap work on other processors?  If not, how does one
turn off the instruction cache on other machines.

   Craig.Treleaven@CanRemote.UUCP

ps:  My UseNet feed has been somewhat irregular recently.  Any
reply would help show it is working!