Someone@Someplace (01/19/90)
Back when I was a college student I had a job programming on a PDP-8/e. Although it only had 4K, it did have an oscilloscope controller which was normally used to control a pen plotter along with a homebrew board to raise and lower the pen. I hacked up FOCAL-8 so that it had instructions to plot to a particular point and control the pen. I put a fair amount of effort into it; but to my knowledge the software was never actually used for real work. Probably, because the PDP-10 in the computer center got a real plotter with software that could only be fantasized about on a PDP-8... During the summer, I was able to borrow a 'scope from the Mechanical Engineering Department and hook it up in place of the plotter. I had gotten a listing of the old PDP-8 Spacewar program from DECUS and had hacked it up so it would run on the 8/e. Among other things, there were different I/O instructions for the 'scope and the timings had to be changed. The resulting game was a good deal of fun, and my friends and I would while away many hours playing it. We had an idea of buying a PDP-8/a and setting it up with a quarter-eater in a bar, but lack of funds prevented the project from getting anywhere. This was the mid-70's, before the video game craze... The other fun thing I did was music taking advantage of RFI generated by the core. What I wrote was an interpreted system which took a pitch number and a duration. It would use the pitch number to index into a table of addresses which it would indirect jump to. Most of memory consisted of no-op's followed by a jump back to the interpreter. The result was some nice square waves, albeit a bit out of tune in the higher notes...