[CCTECH] Interesting tidbit on 6502

From: J.C. Wren <jcwren_at_jcwren.com>
Date: Fri Jun 7 08:26:01 2002

This only occurred in the very first step level of the 6800 released, IIRC.
You'd be hard pressed to find any parts with this flaw. And even if you
should wind up flaming a part (which are astromical odds these days), 6800s
are still readily available.

        --John

-----Original Message-----
From: cctalk-admin_at_classiccmp.org [mailto:cctalk-admin_at_classiccmp.org]On
Behalf Of Ben Franchuk
Sent: Friday, June 07, 2002 02:04
To: cctalk_at_classiccmp.org
Subject: Re: [CCTECH] Interesting tidbit on 6502


Loboyko Steve wrote:
>
> I'm building a 6800 machine right now and I was
> wondering about this "Halt and Catch on Fire"
> instruction. Is this for real. This is a serious
> question. Is there actually an instruction that will
> overheat the chip?

Not on the 6800 but I believe some FORTH chips have that problem.
This instruction for the 6800 if remember right just continually
increments the address bus, ignoring any data read. Only a hard
RESET will reset the machine from this state. I think the opcode
is $00.
Received on Fri Jun 07 2002 - 08:26:01 BST