PDP1 3536

The Xerox 8700 and 9700 lasers were sheet-feeders, but certainly they were mechanical marvels. Had an LSI-11-23 running RT-11 as the on-board controller. Basically Xerox's largest copier with a laser imager instead of the copy glbutt. Programmable fonts, multiple blank-paper hoppers, duplexer for double-sided printing.

At one point, Marlboro engineering decided that 62 printers on the floor of one building was becoming too unwieldy, so Paul Kyzivat headed up a project to replace them with 2 print servers with the big Xeroxes. Since the only documented host interface on the printers was IBM 1401 printer emulation, ACC built a UNIBUS board that emulated an IBM selector channel, for which I wrote the onboard firmware (the on-board micro was a Z80) and VMS device driver, while Paul wrote the VMS spooler "symbiont". I got to spend a week in Marlboro at system integration shakedown. Lots of fun. Must have been 1986 or 87. When I left, Paul got me booked to ride the corporate helicopter to Logan airport.

The 9700 would print about 60 pages per minute. But the pipeline had to be flushed between jobs, took about 15 seconds. The separator pages were separate jobs as far as the printer was concerned; that took a huge chunk out of overall system performance.

Later, we put clones of this installation at several universities, including University of Minnesota (where it was fed from a CDC Cyber 2xx) and Gallaudet University in DC.

Lars Poulsen