[net.micro.68k] Possible Mac Upgrade Questions

ravi@eneevax.UUCP (Ravi Kulkarni) (01/27/85)

I was wondering how hard it would be to replace the 68k on the
mac with a little board that would contain a 68020,fpu and mmu
and plug into the 68k socket. I don't think interfacing the
68020 would be that hard since it has dynamic bus sizing. Is
there a chip set available for the 68k series equivalent to the
3 chip set offered by national in it's 32000 series, namely the
demand paged mmu, and floating point unit and cpu unit? I would
be interested in knowing some of the technical issues involved
in trying to put this in a mac both hardware and software wise.
One other question is how much improvement can be expected by
just replacing the 68000 with the 68020 at the same clock rate
and maintaining the 16 bit bus?


-- 
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chuqui@nsc.UUCP (Chuq Von Rospach) (01/31/85)

In article <227@eneevax.UUCP> ravi@eneevax.UUCP (Ravi Kulkarni) writes:
>I was wondering how hard it would be to replace the 68k on the
>mac with a little board that would contain a 68020,fpu and mmu
>and plug into the 68k socket. I don't think interfacing the
>68020 would be that hard since it has dynamic bus sizing. Is
>there a chip set available for the 68k series equivalent to the
>3 chip set offered by national in it's 32000 series, namely the
>demand paged mmu, and floating point unit and cpu unit? I would
>be interested in knowing some of the technical issues involved
>in trying to put this in a mac both hardware and software wise.
>One other question is how much improvement can be expected by
>just replacing the 68000 with the 68020 at the same clock rate
>and maintaining the 16 bit bus?
>

The 68020 replacement question was handled by Lon Poole in this months
Macworld. Rather than type it in, I refer you to his column...

chuq
-- 
From the ministry of silly talks:               Chuq Von Rospach
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