On Wed, 26 Jul 2000, Jason R Thorpe wrote:

> Aren't all the R4000 mipsco boxes ARC-like?  The Magnum 3000s are
> all R{2,3}000, yes?

I have only seen a R4000 mipsco box once - and that was running RISC/os
5.01
The Magnum 3000 range are all R3000 based.  From my observations the first
digit of the model number is generally indicates the CPU type.

R3000 are all physically indexed, write thru with invalidate, direct
mapped caches.  I'm not aware of any variations to that rule.

As for R4000 caches - they are virtually indexed with physical tags at the
first level.   Outside the chip they will be physicaly indexed, but
depending on hardware design they could have unified or seperate I and D
caches.

Wayne
--
  _____	   	Wayne Knowles,  Systems Manager
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