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From: rhyde@feller.ucr.edu (randy hyde)
Newsgroups: comp.sys.apple2
Subject: Re: BRK Reality
Message-ID: <11389@ucrmath.ucr.edu>
Date: 24 Jan 91 00:46:31 GMT
References: <278d0eda.563e@petunia.CalPoly.EDU> <91015.000214AABENSON@MTUS5.BITNET> <11204@ucrmath.ucr.edu> <1991Jan17.072144.12928@ux1.cso.uiuc.edu>
Sender: news@ucrmath.ucr.edu
Reply-To: rhyde@feller.ucr.edu (randy hyde)
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BRK and COP have signature bytes.


You're right, the latest WDC literature explains the bug in the BRK in
this fashion.  Originally, though, BRK was a one byte instruction with
a bug in the microcode which pushed the return address.
*** Randy Hyde