Subject: Re: Which '040 is this?
To: None <amiga@NetBSD.ORG>
From: Patrick Phalen <pphalen@crl.com>
List: amiga
Date: 02/02/1996 12:47:29
>>     The cpu has XC68040HRC25M printed on top along with a smaller block
>                    ^^^^^   ^^
>Obviously, it's a 68040/25MHz.  A Full '040.  The EC040's (XC or MC68EC040)
>had a disabled or nonexistant MMU, and the LC040's (XC of MC68LC040) had
>a disabled or nonexistant FPU (Floating Point Unit... Aka the Math
>Coprocessor).

Okay, now I'M confused. Following is a quote from a review (May 1993) in
comp.sys.amiga.reviews of the Progressive Peripherals Inc. Mercury 68040
accelerator for the Amiga 3000:

------------
  "The 68040 supplied was not a production chip, but was designated
  'XC68EC040RC25'.  Contrary to my first angry conclusion, this chip DOES
  have a full 68040 with MMU and FPU inside, but it has the less advanced
  bus system of the 68EC040.  Also, the "XC" designation means it has at
  least one minor bug (in the design), and is therefore only for prototyping
  purposes.  I have, however, had no problems with it, and it performs in
  every way like a full MC68040."
------------

I'm looking for an accelerator for my 16MHz A3000 which hopefully can
accept 4MB of SIMMs which I already have. This card would seem to do that,
except for the question about the MMU.

Is my thinking correct? I have the 16MHz A3000 with 2M Chip and 2M Fast and
I have the 4M SIMMS with nothing to plug them in. Rather than pay a premium
for rare 1x4 Zips, wouldn't it make more sense to buy an accelerator with
room for the SIMMs?



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