🚀 go-pugleaf

In article <Dme8D3w160w@gendep>,  writes:
> emmo@moncam.co.uk (Dave Emmerson) writes:
> 
> > Which other 2nd/3rd/4th generation processor has this b****y stupid 
> > 'protected' mode? 
> 
> [deleted]
> So basically what it comes down to is that Motorola is working with
> design ideas that are about 6 years younger than Intel's.  But what
> would happen if, say, the world turned to 64-bit microprocessors?
> Motorola's 32-bit linear address space couldn't be retained without
> (you guessed it) something resembling Intel segmentation.  The
> newer Intel processors would be in pretty much the same boat, even
> in protected mode, for the same reasons.
> [more deletions]

I generally agree with most of the article, but the above extract just 
doesn't hold water. 64 bit processors have been around for some time
btw, ask AMD.
A 64 bit register/address 68xx0 would cope very easily with all current
software without ANY extra mode instructions being needed. If you are
familiar with 680x0 assembler, consider what happens when you do a 16
bit load into an address register. The MSB automatically gets extended
into the upper 16 bits, right? So, literally all that's needed is for
32bit loads into 64bit address registers to follow the precedent.

Such a powerful processor would in any case very likely have more
registers than its predecessors, so while that mode is applied to the
bottom 8 A & D regs, the new ones would be true 64 bit registers AF..8
and DF..8 to give new programmes access to the processor's real power.

This is all speculation of course, the *facts* I have had from MOT are
covered by a non-disclosure agreement, and cover a different aspect
entirely, but I can tell you that the 680x0 is only in its infancy,
even now, unless they eventually kill it off to promote the 88xxx, and
that won't be for a while yet, the 88xxx isn't well enough established.

If you're *really* interested, try to wangle an invite to one of the
seminars, it can be quite enlightening, and gives you some idea which
way things are going in the next few years.

ATB

Dave E.