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From: scott@bbxeng.UUCP (Engineering)
Newsgroups: comp.sys.m68k
Subject: Re: Enclosed: One new opcode for your 68020 system!
Message-ID: <212@bbxeng.UUCP>
Date: 30 Aug 89 15:47:05 GMT
References: <7784@cbmvax.UUCP>
Reply-To: scott@bbxeng.UUCP (Scott-Engineering)
Organization: Basis International, Albuquerque, NM
Lines: 20

In article <7784@cbmvax.UUCP> bryce@cbmvax.UUCP (Bryce Nesbitt) writes:
   >
   >Number three on my "wish list" of 680XX opcodes is:
   >
   >		tst.l	a0
   >
   >As we all know, this instruction is documented as illegal in all Motorola
   >documentation.  68000 processors take an illegal exception.  The 68020
   >and 68030, however will properly execute tst.l a0 (!).

I always thought it was strange that the 68000, which is picky about
odd/even addresses, did not have a bit test instruction for an address
register.

-- 

---------------------------------------
Scott Amspoker
Basis International, Albuquerque, NM
505-345-5232