Re: [stella] "Illegal" opcodes

Subject: Re: [stella] "Illegal" opcodes
From: Russ Perry Jr <slapdash@xxxxxxxxxxxx>
Date: Sun, 18 Jun 2000 23:55:20 -0500
At 12:19 AM -0400 6/19/00, Erik Mooney wrote:
>>I've always wondered why they didn't just tie off any used opcodes as
>>NOPs to actually MAKE them unuseable.

>As I said, because tying them off as NOPs would increase complexity and
>cost for an actual _reduction_ in chip functionality, which is rather a
>bad idea on the engineering level.

True, you said that; sorry I didn't recall that while responding.  That
does make some sense.  BUT!

>I'd still maintain that the chip designers knew exactly that those
>operations would result from those opcodes and intentionally left it
>that way.

Then why not document them?

I imagine they may have planned to announce new opcodes in the next
release?  :-)
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