Re: Hardware and 8MHz 68000 machines

[Stephen Usher <Stephen.Usher@earth.ox.ac.uk>]

>Steve Usher writes
>
>> Which is why I would suggest that TOS-domain processes should be assumed to
>> be non-relocatable, provided with only contiguous memory and live in
>> physical address space. Of course, all the normal hardware would appear in
>> its physical address space whatever.
>
>Sounds reasonable.  Should we add a domain mode, or simply assume that domain
>1 applications are smart enough to run in virtual memory?  I personally think
>it'd be safest to add a domain.

Maybe we should have a totally separate binary type with a new magic number.
This would allow us to get past the problem of stack allocation. The new
executables would let the OS assign the initial stack, at the top of VM. The
MC68030, MC68040 and MC68551(?) all have page table formats optimised for
stack VM. We could also implement malloc in a Unix-like way too using sbrk()
etc. Of course, this is but a pipe dream.

>> Hmm... but the majority of Atari users are still running 68000 based
>> machines. This means that we MUST cater for them if at all possible. Hence,
>
>It would be a nice way to finally get the Atari crowd to go for the 030
>and higher ranges if we would say:  forget the 68000.  I really don't
>understand that even Atari themselves don't see this point.  I mean
>1) developing MiNT and MultiTOS is plainly much harder if one keeps trying
>to keep everything 000 compatible and 2) it is simply going to cost Atari
>money because people will stick to their STs.  An average PC user upgrades
>his/her whole system at least three times as often as the average Atari
>user.  That's fine, but it shouldn't get out of hand.  The 68000 is history.
>Developing a new system supporting history is foolish.

But how many will merely drop the ST and buy a PC instead? The only reason
the PC clone is around is due to backward compatiblility, it's quite a
strong force in the market.

>-- 
>Annius V. Groenink | E-mail: avg@cwi.nl      |  Private & ZFC:
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Steve

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