[comp.sys.mac] Rumours on slotted/colour/68020 Mac?

puckett@gidday.dec.com (Open the pod bay doors please HAL) (11/26/86)

As the usual Jan/Feb announcement is fast approaching, have any of the 
rumours about the new Mac gained in concreteness? My question now is 
whether to but a Mac+ or wait for something better. Has anyone heard of
any compatibility issues w.r.t. large screens, 68020, OS changes, etc?
If the processor family is as upward compatible as it claims, why does
MacWrite need a patch to work with Levco's 68020?

= Giles Puckett = 

miker@uwmacc.UUCP (m radovancevich) (11/27/86)

In article <6601@decwrl.DEC.COM> puckett@gidday.dec.com (Open the pod bay doors please HAL) writes:
>whether to but a Mac+ or wait for something better. Has anyone heard of
>any compatibility issues w.r.t. large screens, 68020, OS changes, etc?
>If the processor family is as upward compatible as it claims, why does
>MacWrite need a patch to work with Levco's 68020?
>
>= Giles Puckett = 

Just because a CPU is upwardly comptible, it does not mean that the programmers
are.  Macwrite 4.5 does some not so nice things with the TRAP instructions
that cause problems on the 68020.  There is a good write up on this and other
68020 concerns in the Technical Notes section of the November Mac Tutor.

There is also a Tech Note from Apple (#2?) that may cover compatibility
problems.

That issues Mousehole Report also mentions the new machines from Apple
and probably the most interesting item is that Rusty Hodge thinks that
Apple will hold the new big machine for the 68030.  I don't know about
that one.  Unless they have been planning on using it for some time, the
recoding of the OS and redesign of the motherboard will cost lots of
$$$ and time.  But 8 MIPS sounds nice...


Mike Radovancevich

rs4u#@ANDREW.CMU.EDU (Richard Siegel) (12/01/86)

"If the processor family is as upward compatible as it claims, why does
MacWrite need a patch to work with Levco's 68020?"

The processor is not the problem; it's the way that MacWrite calls ROM
instructions directly, instead of going thru the Mac trap dispatcher as most
right-thinking Macintosh applications do. Apparently the code for MacWrite is
so convoluted and hacked-up, if Randy Wigginton ever gets hit by a truck and
dies (god forbid), we're never going to see another version of MacWrite...

Personally, I think he oughta rewrite it...

		--Rich