The Imlac PDS-1 is a graphical minicomputer made by Imlac Corporation (founded in 1968) of Needham, Massachusetts. The PDS-1 debuted in 1970 and is considered to be the predecessor of all later graphical minicomputers and modern computer workstations. The PDS-1 had a built-in display list processor and 4096 16-bit words of core RAM. The PDS-1 used a vector display processor for displaying vector graphics as opposed to the raster graphics of modern computer displays. The PDS-1 was often used with another flagship Imlac product, a typesetting program called CES.
The PDS-1 was used in many pioneering computer applications. The FRESS hypertext system had enhanced capability and usability if accessed from a PDS-1 system; the user could make hyperlinks with a light pen and create them simply with a couple of keystrokes. Multi-window editing on FRESS was also possible when using the PDS-1.
The PDS-1 also had the capability to run remote graphical programs such as those that ran on the Stanford AI Lab's main computer. The PDS-1 was also able to run Mazewar, the first online multiplayer computer game. The PDS-1 connected to a host PDP-10 computer (located at MIT) running ITS over Arpanet and the Mazewar program. Up to 8 players running PDS-1 minicomputers or other terminals could access MIT's Mazewar host. The PDS-1 was also important during the early days of Arpanet when network graphics protocols were under consideration.
I used to work at Imlac in Needham, MA back in 1975. I was an electronic assembler/tester and built the CRT monitors and light pens. I remember getting a -1450 volt shock from a defective light pen! We used to make 100 foot cables by pulling the wire bundles through a shrink wrap tube. We used talcum powder to help get the cables pulled through!
Saturday 23rd April 2011
Gary Paresky (Massachusetts/USA)
In 1972 I was assigned to develop a process to proofread text destined for composition on a Photon 713. This was a phototypesetting process that used Friden keyboards producing paper tape from manuscript. The PDS1 system was to be used to proofread text without first running the tape on the Photon 713 projected onto photosensitive film. Our PDS1 system consisted of the display, keyboard, additional keyboard, AB Dick printer with embedded 7" flat faced monitor projecting text to electrostatic paper and paper tape reader/writer. We designed 1,300 unique characters to match shape and spacing of Times Roman medium, italic, bold and bold italic font as well as the 4 faces of the Univers Medium font. The process was a complete success except for the inability of the AB Dick copier to keep the toner solution fully mixed. The system was the equivalent of desktop displays currently available back in ''72.
Saturday 3rd June 2017
Bob Rasmussen (Maryland, United States)
I had a personal Imlac PDS-1 at the University of Utah for the graphics of the fluid mechanics calculations I was doing in the early 70''s. It seemed to work pretty well. Lots of curve drawings using 5th order spline functions, sending stuff to UCLA and getting it back over the Arpanet. Isometric and contour plots. Lots of interesting people were working there then$$Dave Evans, Ivan Sutherland, and Tom Stockham. I was with the Divispon of Artificial Organs with Harvey Greenfield and Dr. Willem Kolff, inventor of the artiificial kidney and a founder of ASAIO. I feel blessed to have been there then.