[comp.sys.m68k.pc] The new 68's

KHINDRIA@MCMASTER.BITNET.UUCP (12/03/87)

So what are the latest rumours about the next 68 series chips?

How fast will they be this time?  What changes are they making to the

architecture ?

alan@pdn.UUCP.UUCP (12/04/87)

In article <8712031748.AA04874@lilac.berkeley.edu> KHINDRIA@MCMASTER.BITNET (Vivek Khindria MUMC x2439) writes:
>
>So what are the latest rumours about the next 68 series chips?
>
>How fast will they be this time?  What changes are they making to the
>
>architecture ?

I assume you already know about the 68030 (available now, costs about
$500, depending on MHz, complete software compatibility with '020,
not pin-compatible)?

Motorola has publicly stated that there will be a 68040 with initial
availability around 1989.  There have been various rumours concerning the
speed and architecture.  One rumour had it that the '040 would be a
64-bit cpu with a 128-bit data bus with a clock cycle of 100 MHz.
I do not believe this rumour.  EDN magazine reported that the '040
would be implemented using combinatorial logic instead of microcode
for all the commonly used instructions so that they would execute in
one machine cycle--thus bringing the average cycles per instruction down
close to one.  EDN also stated that other unspecified RISC-like features
would be incorporated into the design, and that the intent (hope?) is
that the thing will do 40 MIPS sustained.  Nothing was said about
any new features that would lead to software compatibility problems.
In view of the 78000 project (a true RISC processor due 1Q88), I doubt
that Motorola feels the need to emulate Intel and introduce any significant 
software incompatibilities.  As for hardware compatibility, each
generation to date has had problems, and you should not expect good news
(that way you might be pleasantly surprised some day).

Hope this helps.

--alan@pdn