In part 1 of this series, I left you with the cliffhanger of whether or not 15-year-old me was able to collect the $500 needed to purchase one of the first commercial microcomputers. Here’s what happened next.
It didn’t take long for me to discover that $500 only bought the CPU. Many early purchasers of these machines soon tired of toggling simple binary programs into the limited memory just to watch some lights blink, only to lose it all when the power was turned off. It would take at least another $500 to make this machine useful, with some form of operator interface and mass storage, like a teletype with paper tape reader. My first job came along and I was making $2 per hour — I was going to have to work a long time at that rate! I could not wait so long.
I was now in high school, the electronics program at Dauphin County Technical School. Here, I found and soon mastered a digital electronics trainer capable of simple computer projects and further enhanced my desire for that microcomputer. It was hard to save now that I needed a car to get to work. After two years, I only had a quarter of what I needed.
Then, along came SD Systems and its Z80 Starter Kit. This was a much more reasonably priced computer that had a very rudimentary operator interface (but much easier than toggle switches), and the capability to connect a common, inexpensive cassette tape recorder as a mass storage device. I sent my check to them, and two weeks later, I was the proud owner of a microcomputer!
By this time, I was in college and had completed my mandatory FORTRAN course, so I understood the fundamentals of computer programming — that is, the ability to order processes sequentially and to never assume anything. The Z80 Starter machine did not have a FORTRAN compiler; the only way to program it was in Z80 machine language. Further, there was no assembler either, so all programs had to be hand-assembled.
Machine language was probably one of my most intensive learning experiences of my life. I wrote programs to do many practical things on this little computer, like industrial control interfaces and giving the computer the ability to connect to other computers and terminals. However, it was not long before I wanted more. I still wanted that “bigger” computer feel and the ability to write programs in FORTAN and BASIC. And I wanted to play some of the computer games that were emerging at the time, like “Star Trek” and “ZORK!”
One of the selling points of the Starter Kit was the future expansion possibilities. As one can see in the upper left corner of the photo included with this post, there are two sets of double-row pads numbered from 1 to 100. These were meant to accommodate two connectors, and these two connectors were identical to the connectors used in the larger computers I was wishing to own years earlier. My ultimate goal since the purchase of the Starter Kit was to add the connectors and buy additional plug-in circuit boards that would evolve the Starter Kit into an Altair-like microcomputer.
Did I get there? You will have to tune in to part 3 for this answer, along with how this growing interest and skill turned into a career I still enjoy today. But in case you were wondering, the Z80 Starter Kit still works!
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