[Gllug] Beagle Board

[Richard Jones]

On Mon, Jan 12, 2009 at 01:41:14PM -0500, Andrew Farnsworth wrote:
> Ok, so I over simplified a bit.  Yes, you can do it on the older
> hardware but it was not directly supported by the CPU, unlike
> today's CPUs or even those from the 68030 (68020 even maybe, but it
> didn't have a separate mmu which the 030 did) did.  These CPUs had a
> hardware interrupt that regularly tripped and was easily used for
> preemptive multitasking.  It is/was possible to do on older
> hardware, but it was not standard across the board by any stretch of
> the imagination.

Even the ZX80 had a regular non-maskable timer interrupt.  As do all
PCs since the very first one (ie. the Intel 8253).

Not sure anyone ever tried to do pre-emptive multi-tasking on a ZX80,
but it wouldn't have been the hardware that prevented it.

Rich.

-- 
Richard Jones
Red Hat
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