One reason that it was practical to implement AppleTalk in both the Mac and LaserWriter at the same time was that the LaserWriter, by design, looked like a Mac to much of the software. It used the same 68000 CPU (processor) as the Mac, and the same SCC (serial communications) chip.
The LaserWriter was actually more powerful technologically than the original Macs that were hooked up to it:
- The LaserWriter’s 68000 chip ran at 12MHz, versus 5-8MHz for the Mac.
- The LaserWriter had 512KB of RAM, versus 128KB in the Mac.
- The LaserWriter’s ROM was 512KB, versus 64KB for the Mac.
And of course the LaserWriter cost $7000 ($21,000 in today’s dollars) versus the original Mac’s $2500 ($7400).
The LaserWriter was Apple’s most advanced computer at the time because it needed to be able to interpret Postscript and convert(rasterize) the pages Postscript described to individual pixels to then be printed on paper at 300 dpi (dots per inch).
The LaserWriter’s high cost (and large size), however, were due more to its underlying Canon print engine than to its advanced electronics. It was the combination of that new print engine, Postscript, and the Macintosh itself that ultimately brought us all the Future that was Desktop Publishing.
