Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!apple!well!stevef
From: stevef@well.UUCP (Steven Robert Fordyce)
Newsgroups: comp.sys.atari.st
Subject: Re: CMI MC68000 Processor Accelerator Board
Keywords: CMI, accelerator
Message-ID: <12635@well.UUCP>
Date: 10 Jul 89 02:03:49 GMT
Reply-To: stevef@well.UUCP (Steven Robert Fordyce)
Organization: Whole Earth 'Lectronic Link, Sausalito, CA
Lines: 59

I work for Creative Microsystems, Inc. and am one of the designers of our
accelerator for the Atari ST.  There has been some confusion about our
product and our company which I would like to clear up.

The first ST accelerator we are shipping is for the older style 520's and
the Mega (the same board works for both).  These boards will start shipping
early next week.  The version for the 520 STFM and 1040 will be out
later.

It is not necessary to remove the 68000 to install our board (you can if
you want, but it is easier not to).  We provide a socket that you solder on
top of the 68000.  Our board plugs into that.  Three pins on the 68000 have
to be cut where they go into motherboard, and there are four wires that
have to be soldered to the motherboard and connected to our board (we
provide the wire harness with a connector on it).  That's all there is to
it.  If you are uncomfortable doing the installation you can have your dealer
do it.

Fast ROM is a feature our board offers that speeds operation up quite a
lot, but it is not necessary for our board to work.  All versions of the ST
are designed to run at 8 MHz.  Our board (and the others) run the CPU at 16
MHz.  The rest of the computer can't run that fast, so circuitry on our
board slows down communication between the CPU and the motherboard so that
the motherboard can't tell our board from the stock 8 MHz CPU.  This is why
an ST with our board (or either of the other two accelerators for the ST)
doesn't run twice as fast as the standard ST.  Using Fast ROM allows our
board to access the ROM's at twice the normal speed.  The TOS operating
system is in ROM, and most Atari software makes a lot of ROM calls, so Fast
ROM offers a substantial improvement over standard 16 MHz operation.

You can modify your ST to use Fast ROM either of two ways:  You can get a
two ROM set from us (Atari's two ROM set isn't fast enough), plug them into
our board, and remove the ROM's in the motherboard (they are in sockets);
or if you have an ST with the six ROM set, you can lift two pins and wire
them up as instructed in our manual (one pin is grounded, three wires run
to our board).  You can then use Fast ROM.

Our board doesn't have a cache, and is compatible with all software.  Our
board also comes with a socket for a blitter (which you can get from your
Atari dealer and we are talking to Atari about allowing us to sell them
directly), and a socket for a 68881 math co-processor.

I will be posting speed comparisons between our board, the stock ST, and
the other accelerators soon.

CMI has been in business for more than three years and has been selling
accelerators for the Amiga for a year.  We have a line of products for the
Amiga (but none for the PC), and this is our first product for the ST (but
not the last).

If you have any questions post them to this group, or send me email.  Or you
can call customer support at CMI, (503)691-2552 and ask for Lilliane Carter.

						Steven R Fordyce
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