10 Apr
2005
10 Apr
'05
12:59 p.m.
On Apr 10, 2005 1:02 PM, Scott Stevens <chenmel at earthlink.net> wrote:
The LaserWriter had one of those massive 64 pin DIP
package 68000 chips
on it. Often the LaserWriter had a more powerful CPU than the Macintosh
connected to it.
The size and internal arrangement of the 68000 CPU was identical
between the Mac 128/512/Plus/etc and the LaserWriter (64-pin DIP, 8
32-bit D registers, 8 32-bit A registers, 23-bit address bus, 16-bit
data bus...). The difference was that the computers ran at a nominal
8MHz (less effective speed due to video-induced bus blockages), and
the printers ran at 12MHz.
The 64-pin DIP was the standard 68000/68010 package, and only came in
a Z package (square with pins underneath), and a PLCC package (square,
SMT pins on the sides) later.
I think Eric Smith has the RAM/ROM differences right. The original LW
had 1.5MB of RAM and 512K of ROM, and I _think_ the Plus had an
additional 512K of ROM (more PostScript fonts, IIRC).
-ethan