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PM 6500
Posted by: juan123 on 2007-07-11 18:55:07
Hey my PM 6500 that I recently got has a G3 upgrade. I got that working , but I'm wondering, is there anyway to make the G3 upgrade work AND the 603 processor that's the original, kind of making a dual processor machine? thanks!

Posted by: coius on 2007-07-11 18:59:10
no sorry, once it takes over, it is not compatible to use two different processors, especially when they don't work on the same instruction level. The only way you can use dual processors, is when they both are the same type. There is no system on it that can handle which instuctions go to the CPU that supports a feature, while it doesn't send the same instruction to one that doesn't support a feature.

In anyway, you are stuck as soon as the G3 kicks in, it dissables the processor at hardware level and takes control of the bus. You would have to redesign the north bridge COMPLETELY and probably is not possible on the Mac Systems

The Lisa is the ONLY one I know of that can do that. But it uses the 6502 Chip for the boot and then hands it over to the 68k CPU

Posted by: Maccess on 2007-09-12 22:52:38
It might be possible if you'd write a new enabler extension that would be smart enough to know which instructions to send to each processor.

You'd have to be a really smart software engineer to do that and I would think the odds of that happening are probably higher in PPC Linux than the Mac OS.

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