The Mits Altair 8800 by Daniel F. Clarke

I loved electronics ever since I can remember! And I constantly read electronics books since early high school - right through the 60s and into the 70s and 80s. In the earliest days I think it was Popular Electronics and Radio Electronics that I purchased regularly. I graduated as an Electrical Engineer from the University Of New Brunswick (UNB) in 1971 with a taste of university mainframe computing, so anything that looked like electronics and computers together was of special interest. It all happened in 1974! Just like Paul Allen and Bill Gates, I was completely shocked to see the ALTAIR article in Popular Electronics. I must have read the article about a dozen times. The more I read it the more interested I was in having one. It could not do much more than compute but it was your own personal mainframe on your desk! You had to live in those days to appreciate the feeling. And to dream of what was possible!!!

I had already done some work on microcomputer systems at NBTel where I worked in the Engineering Department. I was aware of the original 4-bit 4004 Intel cpu, the limited 8-bit 8008 and of course the fantastic 8-bit 8080. Any microcomputer system with an 8080 cpu I knew was definitely good. I wrote the software for an NBTel microcomputer-based application and the code was tight because I hand assembled it into 256 bytes of ram, as I recall. We did not have fancy tools like Assemblers and Debuggers. Everything concerning microcomputers was new and you made do with what you had available. My eventual pursuit of a Masters degree in Computer Science (started part-time while at NBTel) would result in me working on assmblers that ran on the IBM 360 mainframe of UNB. But at the time if you had a system with 1K of ram on your bench or on your desk you thought you controlled the world.

It might also be worth noting that at the time I also managed and taught BASIC and FORTRAN time-share programming within NBTel's Engineering Department, so I actually had excellent experience with using mainframe systems all the way down to microcomputers. I knew what the state-of-the-art was in BASIC software for sure.

So I put my order in to MITS. Like everyone else in the world it seemed (the stories quickly spread within weeks) I would have to wait because the demand seemed to overload every aspect of the company that advertised the product. But I did receive my ALTAIR 8800 several months later. I jumped into the assembly and remember that no one else around me was interested in such adventure . so I was totally on my own! I am neat and well organized by nature but I had to take special care on this project because I quickly recognized that the number of components alone plus wiring cables likely would produce a problem. One bad solder joint and I knew that I would work for days to fix the mistake. And even worse would be an intermittent connection. So soldering was done with loving care.

I had no terminal (a teletype, then a CRT came later) so my plan was to test my new ALTAIR with a couple of simple binary programs. Well, when I fired it up, to my surprise, it seemed to be working. I tried a couple of the address functions and they seemed OK so I then entered a binary program and it worked perfectly. I then tried everything that I could think of over the next few weeks and it checked out perfectly. I still remember entering the program that played music on an nearby transistor radio - very cool.

I cannot put into words what this meant to me. The ALTAIR 8800 was a thing of beauty. With a program executing, the flashing of the LEDS were mesmerizing to me. Even the memory test programs were exciting as they executed because of the flashing LEDs. The potential to control the universe seemed almost present in that little Intel 8080 cpu that I knew would cost more than I had paid for the whole ALTAIR 8800, if purchased separately.

Over the next few years I enhanced my ALTAIR with an ASR-33, then with a CRT and with triple 5.25" floppy disks. I ended up purchasing 4K memory cards later and also MITS 8K basic and even a 16K memory card. I experienced all the things that the ALTAIR User was infamous for but I must emphasize that the only thing to me that would have exceeded my experiences with the MITS ALTAIR 8800 would have been personally landing on the moon!

I actually did my Master's project using my Altair. I wrote some special software to support dial-up access to a microcomputer. For me it was a major learning experience. A couple of technical things still come to mind but it's rather fuzzy because its been almost three decades. I remember that I wanted to interface a terminal device (ASR-33 or CRT) and I definitely recall that initially it did not work. This surprised me because I was positive that I had everything perfect. I think that I was connecting the CRT via the serial interface (using a MITS serial card) and the speed setting was 300bps but I am not positive. After a lot of troubleshooting I concluded with the help of a good friend that the capacitor value specified was simply wrong. It was way off and with a simple change it worked perfectly. The other experience that was much more technically challenging was when I was doing my final testing and debugging of my thesis project. My data transmission with the DC Hayes modem card was intermittent. It was good sometimes and poor other times. Almost random but not quite. I finally was able to trace it down to noise problems on the Altair S-100 bus . the actual power lines (5VDC I think). I comfirmed everything with a scope including a simple fix which was more capacitance and high frequency filtering on the power supply. So if you check this out you might see that I made some minor changes on the power supply.

Other than these specific items, I never had a problem with the operation of my ALTAIR over several years of very intensive operation. And in terms of software it was a real treat to use. I can state from fond memories that Bill Gate's 8K BASIC was absolutely superb. I previously had extensive experience with BASIC running on the largest mainframes in North America and I found MITS BASIC to be very fast. So fast that it surprised me because I was conditioned from regular use of time-sharing BASIC and FORTRAN systems. And of course with commands like PEEK and POKE in MITS BASIC you could do all kinds of interesting things.

So in conclusion, as I think is universally recognized, the MITS ALTAIR 8800 was a special innovation that changed the world for the better. In my opinion it was exciting times for those that were true explorers of the power of electronics combined with software to sail into the new age of "personal microcomputing".

If you have ever tried to land the lunar module on the moon using your MITS ALTAIR 8800 while running Bill Gate's original (paper tape) 8K BASIC, you will relate to this fading memory. Words have simply failed me though I tried to share my experience using these rough bytes of ASCII.

Daniel F. Clarke
May 14, 2005

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