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From: cjl@ecsvax.UUCP (Charles Lord)
Newsgroups: net.micro
Subject: Re:HCF
Message-ID: <796@ecsvax.UUCP>
Date: Sun, 3-Mar-85 21:06:18 EST
Article-I.D.: ecsvax.796
Posted: Sun Mar  3 21:06:18 1985
Date-Received: Wed, 6-Mar-85 02:46:00 EST
Organization: NC Educational Computing Service
Lines: 21


HCF was and is alive and well on the 6800. The instruction
(HALT and catch fire) is only an expression, and does not
make the chip burn as some have suggested. The code is really
a useful utility designed by the engineers at Motorola for
testing primative systems. The address counter merely increments
from 0000-FFFF repeatedly until reset. Although handy for 
hardware repair, the code was a villan for many that learned
programming on the D2 or similar manual machines.

  As the same engineers then went to form the company
MOS Technology (the inventer of the 6502), it is conceivable
that they hid the same instruction in the 65XX family.

Anyone who has studied ATE(Auto test equipment) principles
can readily undewrstand WHY such instructions exist!

(See- we still need a NET.DiGITAL!)

                               -Charles Lord
                                cjl@ecsvax