Memories of my trusty old Radio Shack TRS-80
Feb 6, 2008 Technology
The first computer I ever owned was the original Radio Shack TRS-80, and even though computer technology has advanced by leaps and bounds since then, I have never owned a machine that I loved quite as much as that simple gray and black plastic number.
In 1976 the home computer industry was in its infancy. An young engineering student by the name of Steve Wozniak designed and built a computer from scratch using spare parts that he had scrounged from the local Hewlett Packard facility, and the Apple Computer Corporation was born right in the garage of his friend Steve Jobs. Today the company is one of legend.
Recognizing the huge potential of selling simple computers to the masses, Radio Shack put their engineers to work designing what would soon become the TRS-80. It was a very simple machine featuring a Zilog Z80 1.77 Mhz CPU, 4 kilobytes of RAM and a 4 kilobyte ROM chip that contained a very primitive operating system based upon the BASIC programming language. The monitor was a 12″ monochrome jewel that was quite literally an RCA black and white TV – with the tuner missing! Programs and data were stored on standard audio cassette tapes.
Everything except for the monitor and cassette tape recorder/player was housed inside the overstuffed keyboard case, relegating most future system expansion to an optional external unit referred to as an “Expansion Interface Unit”. During its lifetime several options and upgrades became available for the original TRS-80, some from Radio Shack itself, and many others from enterprising 3rd party companies.
An engineer by the name of Steve Ciarcia released a book that gave step-by-step instructions for “hacking” the TRS-80′s circuit board to make it run faster and add several missing features. And when I say “hacking”, I mean that quite literally since a number of the upgrades required using an Exacto knife to actually sever some of the “traces” on the circuit board. Then you soldered in switches, crystals, wires, and integrated circuits, some of which were piggybacked onto existing components. It sure made the inside of the keyboard case a mess, but each and every “mod” worked like a charm!
By the time my own TRS-80 became a paperweight it had been upgraded to the Level II BASIC operating system (in a 12k ROM chip) and 48 kilobytes of RAM. I had also built a 3rd party Expansion Interface Unit from a kit that allowed me to attach a dot matrix printer, a 300 baud modem, and a 180k single-sided, single density floppy disk drive to the system.
Before long Radio Shack introduced a new and somewhat improved version of the TRS-80 dubbed the Model II, and the original units were retroactively given the moniker Model I. Although the company went on to release a number of succeeding computer models, my trusty old hacked-up Model I was the only Radio Shack computer I ever owned.
I have purchased, used, built and sold dozens of personal computers throughout the years, but for some reason not a one of them has meant as much to me as that ancient TRS-80 Model I. By today’s standards it was a proverbial dinosaur, but to a 17 year old boy from “up in the holler” in Widener Valley, Virginia, it was absolutely filled with magic and wonder.
Leave a Reply