Tuesday, August 27, 2013

MMD-1 Vintage 8080 Microcomputer reported to be the First Single Board Computer

 The first single board computer - MMD1
Click on photos to enlarge
Original Prototype MMD1
 The Microcomputer Trainer MMD -1 designed by John Titus is in the Wikipedia listing for Single Board Computers as the first single board microcomputer.

Production Model
We originally called the computer "Dyna -Micro" and the the production units were called "MMD1" - that was just short for 'Mini Micro Designer'. The Wikipedia listing for the single board computer does not mention John Titus as the designer - it does mention the computer was made popular by  Bugbooks. Bugbooks 5 and 6  used with this computer. An
original prototype is on display in our "Bugbook Historical Microcomputer Museum".

John Titus tells in his own words the development of the MMD-1 computer

 The second item about the microcomputer pioneering work by John Titus ----

Dr. John Titus
The  MARK8 computer construction article published in the July 1974 Radio Electronics  by John Titus was a Milestone for the magazine in the computer revolution. According to Wikipedia - Radio-Electronics featured audio, radio, television and computer technology. The most notable articles were the TV Typewriter (September 1973)[1] and the Mark-8 computer (July 1974).[2] These two issues are considered milestones in the home computer revolution.[3]

Here is where you can get a real good view of John's 'MARK8' work - this was put together by authors at Florida Gulf Coast University and was copyright 2007.   

Here are some really nice comments John made about our work together more than 35 years ago.

Me - David

 It has always been a great pleasure for me to be a colleague of Dr. John Titus. The work we did together in the 'Blacksburg Group' 38 years ago was a real highlight in my electronics and computer journey. John is retired and living in Utah near family. Thank you John for the memories.
"By David Larsen" KK4WW Computer Collector Historian  
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  1. i brought one of these home after using it to prototype an automatic filling machine. I taught my then young son to program his train set, taking in sensor inputs as two trains passed microswitches (remember debouncing?) and controlling switch tracks and a speed controller. We measured the quality of his program by how many turns around the track both trains made and the time between "crashes" (not the program, the trains). The trains ran around our living room and Christmas tree and stayed up long after the tree came down. The programming was through the hex keypad and he became adept at using registers and interrupts. We spent hours together, excited, cheering and sometimes frustrated with our efforts and time together. We still, many, many decades later remember that Christmas. He is now teaching his young daughter how to program an Arduino kit, several generations on (electronics and people).

    1. Hi This is a great story - thank you for sharing it with us. It is just wonderful to hear of the success in teaching you son and the bonding that must have taken place. I did a lot of teaching for my son but not much in the field of computers. Have a very Merry Christmas.

    2. David: I do remember your articles and waited each month for them appear, sometimes making notes and breadboarding the ideas. Thanks for all the memories. All the very best.

    3. Hi I am glad to hear about you remembering the monthly articles - We did that for about 5 years and in my files I have copies of all 60 or so. Those articles were a long time ago -- about 77 to early 80's. Thank you for making the comment. Please send me a personal email so I can have a few exchange msg with you. Thank You David


I look forward to your comments and will respond.