This page lists some of the different types of computer hardware that I've been lucky enough to have been able to use during my engineering career and the types of personal or skunk works projects I created. Click the links to see a photo and something interesting about each computer. The pages below this one describe a few of my favorite projects.

Digi-Comp I downloaded June 19, 2018 from
      • Digi-Comp I (1969)
        - A 3-bit mechanical computer made of plastic and springs
      • HP 65 calculator and successors (1975-1982)
        –games (including 4 deck Blackjack in 100 keystrokes), math tools, chemistry tools
      • IBM 5100/5010 (1976-9, BASIC and APL)
        –coin-operated machine management, commercial general ledger and accounts receivable package, games
      • KIM 1 microcomputer (1977-8, 6502 assembler)
        –experiments –cost about $200 in 1977 with 1K RAM and a cassette tape interface
MOS KIM-1 Main Board downloaded April 30, 2012 from click for full size
  • CDC 6600 mainframe (1976-9, BASIC, FORTRAN, and APL)
    –games, chess, 2D graphics, class projects
  • Prime 750 minicomputer (1979-82, BASIC, FORTRAN, Prime assembler)
    –games, chess, APL interpreter –assembly language class projects
  • UNIVAC 1100 mainframe (1981-83, BASIC, FORTRAN)
    –3D visualization software for NASA spacecraft models
    –FORTRAN code that analyzed the radiation exposure at selected points of the spacecraft from the Radio-isotope Heating Units (RHUs) that used 40g slugs of Pu-238 to keep the spacecraft electronic bays warm.
  • HP 9826A microcomputer (1982-4, Pascal, 68000 assembler)
    –3D graphics pipeline, integrated circuit cell design, strategy game design

  • VAX minicomputers (1982-8, C, Unix, VMS)
    – 3D modeling software (HOOPS)
    – An implementation of planer embedding
    – Integrated circuit design and simulation
    – Microcomputer hardware class assignments using various microcomputer simulators
  • Apple II(1983-8, BASIC, Pascal, 6502 and Z-80 assembler)
    – mass properties modeling
    – ported my 3D pipeline on an Apple II with a Z-80 based card running Pascal. I had to squirt freeze-mist onto the card to keep it running.
  • Silicon Graphics (SGI) IRIS 1000 workstation, flight simulator
    Caltech had one of the first workstations with 3D hardware acceleration. It arrived as I was about to graduate but I got to play the flight simulator a few times. At $30K for the workstation, it was the first flight simulators outside of places like Boeing, although the only input was the keyboard and mouse.
  • Applicon Bravo CAD workstation (1987-8, proprietary scripting language)
    – spacecraft instrument field of view visualization
    – spacecraft component modelling
  • MS DOS platform (1983-2005, x86 assembler, Pascal, C, C++, Forth)
    – 2D and 3D modeling, chess, mass properties configuration modeling, Word Perfect mouse and font cache, and much more
  • Microsoft Windows platform (1986-present, x86 assembler, C, C++)
    – 2D and 3D graphics, CAD, chess, Microsoft's Media Control Interface, Piper live action computer game, and much more
  • Linux platform (2011-14)
    - Customization install script maintained by appending a new apt-get command for each new software component
    - To install the new software, just run the script. If you have to restore the OS, running the script gets you right back to the same configuration.
  • QP/Nano real time OS on TI MSP430 microcontroller (2013-4)
    - Prototype spacecraft electronics control code.
  • Intentional Software Platform (2012-present)
    - Aspect oriented application platform. Microsoft acquired Intentional Software in 2017.