Subject: REVIEW: Motorola MC68010 microprocessor
From: [email-masked] (Michael Glew)
Date: 13 Oct 1993 13:14:49 GMT
Newsgroups: comp.sys.amiga.reviews

PRODUCT NAME

	Motorola MC68010 microprocessor

BRIEF DESCRIPTION

	The MC68010 is the third member of the "68000" family of
microprocessors from Motorola.  Replacing your Amiga's 68000 with a 68010 --
an inexpensive, drop-in replacement that does not require a board -- speeds
up the computer by approximately 15%.

	The MC68010 is fully object compatible with the earlier members of
the family and has added the features of virtual memory support and enhanced
instruction execution timing.

AUTHOR/COMPANY INFORMATION

	Name:		VSI Electronics (Australia) PTY LTD

	Telephone:	Melbourne     (03) 543 6445
			Brisbane      (07) 52 5022
			Adelaide      (08) 267 4848
			Perth	      (09) 328 8499
			Sydney office (02) 439 4655
			Sydney sales  (02) 439 8622

	[MODERATOR'S NOTE:  The MC68010 is made by Motorola, obviously.  VSI
	is the Australian distributor for Motorola.  - Dan]

LIST PRICE

	$300 (Australian) for 10 units.

	VSI only supplies these chips in lots of 10, so you are better off
buying privately like I did.  I picked up one for $25 which included the
programming reference card and advance information booklet.

SPECIAL HARDWARE AND SOFTWARE REQUIREMENTS

	HARDWARE

		An Amiga with a 68000 CPU.

	SOFTWARE

		AmigaDOS 1.3 or later is recommended.

COPY PROTECTION

	None.

MACHINE USED FOR TESTING

	Amiga 500
	1MB Chip RAM, 8MB Fast RAM
	Kickstart/Workbench 1.3

REVIEW

	A while back, I heard about the 68010 CPU and how it was more or less
fully compatible with the stock 68000 in my Amiga 500, and that its mul/div
capabilities were sped up.  This sounded like a cheap alternative to an
accelerator board, so I decided to buy one.

	I shopped around and discovered that either the price was in excess
of A$100, or else the chips were available only in bulk.  So I decided to
try buying one privately.  This was a good move as there were quite a few
people out there wanting to sell.  I ended up buying one from a guy in
Melbourne.

	Now, all I had to do to install it was to take the screws out of the
back of the Amiga's case, remove the RF shielding, remove the 68000, fit the
68010, replace the shielding, and replace the screws.

	[MODERATOR'S NOTE:  If you are not comfortable opening up your
	Amiga, then you should have the work done by an authorized Amiga
	service center.  Opening your Amiga yourself may void your warranty,
	and careless work may even damage the machine.  - Dan]

As hoped, when booted up, the Amiga functioned normally.  In benchmarks, the
speed increase was moderate at around +15%.

	Another feature that I discovered was a cache-loop mode.  Very small
assembler loops run much faster.  Specifically, this is called the DBcc
looping primitive instruction.  For example:

		lea	SOURCE,a0
		lea	DEST,a1
		move.w	#LENGTH,d0
	LOOP	move.w	(a0)+,(a1)+	; this section will run super-fast
		dbeq	d0,LOOP		; because no instructions are fetched

	There is a down side though.  If you're running under AmigaDOS 1.2
or lower, then some programs will not work.  This is because the programs
were written without taking into account the new stack pointer.  Basically
this is the same for all later CPU's also (68020, 68030, 68040, etc.).  So
if a program won't work with the 68010, then it won't work with a 68020+
either.  Try the 1.2 version of the Amiga's Calculator.... 8)

DOCUMENTATION

	The documentation is available in booklet form, separate from the CPU
itself, but I don't know what it costs.

	The documentation is technical, so if you don't know much about
electronics or assembler then you'll be lost.  But the information is very
complete for a technical person.

LIKES AND DISLIKES

	Overall, I'm pretty impressed.  Gives a little extra power to your
raytracing, although 68000's were never meant for raytracing anyway.  Oh,
and yes, raytracing is still very slow - but just think, a raytrace that
takes a full day on a 68000 will be quicker by 3.13 hours with the 68010.

COMPARISON TO OTHER SIMILAR PRODUCTS

	Adding a 68010 is different from adding a standard accelerator board.
The 68010 uses the same clock as the 68000, so there is no faster clock-speed
to contend with.  With faster clocks, you have to get faster RAM usually.
Since this uses the standard clock, no change in RAM speed is needed.

BUGS

	As mentioned above, some Amiga software will not work with the 68010
and higher processors if you are running AmigaDOS 1.2 or lower.  There is a
PD patch available called deciGEL, which works as far as I could tell.

VENDOR SUPPORT

	VSI doesn't really want to cater to small purchasers.  For a company
to tell an individual who wants a chip that he'll have to buy 10 is a bit
hard to swallow.

WARRANTY

	None.

CONCLUSIONS

	The 68010 is a good speedup for the budget-minded user; however, if
you want real speed, buy an accelerator board.

COPYRIGHT NOTICE

	Copyright 1993 Michael Glew.  All rights reserved.

---

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