On 26/10/2011 00:44, The Natural Philosopher wrote:
Tim Streater wrote:
In article om,
"dennis@home" wrote:

"Tim Streater" wrote in message
...
In article m,
"dennis@home" wrote:

"Steve Firth" wrote in message
-september.

org
...
"dennis@home" wrote:
[snip]
If only Apple had allowed the clones to build Macs back in the
80s

yes we would still be stuck with an OS that didn't even do
virtual memory.
Windows did that for years before macOS.

No that's bull****. It would have been accurate had you said
that Windows
had protected memory before MacOS.

Well that's not surprising.. it wasn't until the 68030 series came
out that there was a working MMU to run the protection and
coincidently support paging and VM.
That is true for Motorola CPUs as used by Apple.

Mmmm no (again). The 030 was the first in the 68k line to have an
*on-board* MMU. You could perfectly well use a 68020 and use the
68851 MMU as a co-processor with it.

Which MacOS used one of those?

The later versions of classic MacOS, with virtual memory, would
certainly have run on an 020 Mac with MMU.

Anyway they didn't work very well.

Do you mean the 020? (Used in the TGV and Eurofighter according to
WinkyPedia). Or the MMU.

Having written a tiny OS for the 68000 (see
http://www.clothears.org.uk) I can state that it's a much better
processor than the 8086 ever was. Just a shame that the 68008 wasn't
out in time for IBM to use in the original PC instead of the 8088.

+1
Far better chip.

Segmentation was a complete ******* without proper paging 386 was first
DECENT 32 bitter

'286 would have been ok(ish) if it were not for the legacy of PCs and
DOS. You really needed the complexity of the 386 to tame those. The 386'
was the first processor I met where it took 20 mins to acclimatise to
the new assembler, and then months to get a handle all the wrinkles of
the architecture.

--
Cheers,

John.

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