Introduction

The TRS-80 Model III was a popular computer introduced by Radio Shack in 1980. It was the successor to the TRS-80 Model I and featured significant improvements in terms of hardware and software. It was a popular choice among home users, small businesses, and schools.

In this post, we will take a closer look at the TRS-80 Model III, its features, specifications, history, and impact. We will also explore its place in the history of computing and how it influenced future generations of computers. Finally I will provide my personal experience with using what many of us affectionally called the “Trash 80”.

Let’s talk about the specifications

The TRS-80 Model III was powered by a Zilog Z80 microprocessor running at a clock speed of 2.03 MHz. It came with 16 KB of RAM which could be expanded up to 48 KB along with featuring a built-in video display with a resolution of 80×24 characters, and it supported both upper and lowercase letters. It also had a built-in speaker for sound output.

The two 5.25-inch floppy disk drives, each capable of storing up to 180 KB of data provided adequate storage all things considered. It also had a full-stroke keyboard with a separate numeric keypad and function keys. It offered decent expansion as it also had a serial port, parallel port, and an expansion bus for adding peripherals.

Software

The TRS-80 Model III came with the TRS-DOS operating system, which was a modified version of the CP/M operating system. It also came with several built-in software programs, including a text editor, a BASIC interpreter, and a file manager. I cut my teeth on this big bulky machine and with the books it came with, taught myself to write code in BASIC. Only thirteen at the time, I was enthralled with the new world I discovered and quickly found myself building text-based adventures.

Early on I had picked up a few software titles that honestly I couldn’t tell you the names of today, however, a particular fantasy RPG stands out as I ended up reverse engineering the game to promote my characters without grinding my way there. The “save the damsel stuck in the dungeon” title was produced by a Canadian software developer and my parents allowed me to call him to ask about parts of his code and why he made certain choices in logic. He couldn’t believe a thirteen year old was actually having a software development discussion with him and had hacked his game so easily.

Although I never owned it a the time, one of the most popular software programs for the TRS-80 Model III was VisiCalc, which was a spreadsheet program. It was one of the first killer apps for personal computers and helped popularize the use of spreadsheets in business and finance.

History

The TRS-80 Model III was introduced in July 1980 and was initially sold for $699. It was designed as an affordable and easy-to-use computer for home users, small businesses, and schools. It was a significant improvement over the TRS-80 Model I, which had been introduced in 1977.

My parents sprung for the dot matrix printer and eventually I saved up for a voice synthensizer module that I bought for $200 from a computing magazine.

This early personal computer was a commercial success, selling over 100,000 units in its first year of production. It was also well-received by reviewers, who praised its ease of use, expandability, and affordability. Sometimes I would spend hours typing in endless lines of Z80 code in an effort to play the next coolest game that would come in the computer magazines each month. They always remind me of the prizes we would love to dig out of the bottom of our cereal boxes.

Impact on Future Computing

The history of computing in my opinion would frankly not be the same if it were not for the mighty TRS-80 Model III. It was one of the first computers to be targeted at home users and small businesses, and it helped to popularize the use of personal computers in general. For me, it started my love of computing and launched my career at a very early age.

It’s worth mentioning its expandability as it had an expansion bus that allowed users to add peripherals such as printers, modems, and hard drives. This expandability helped to make the TRS-80 Model III a versatile computer that could be used for a variety of tasks.

Finally the TRS-80 Model III came with several built-in programs, including a BASIC interpreter and a file manager. It also supported a wide range of third-party software, which helped to create a thriving ecosystem of software developers and users.

Conclusion

The TRS-80 Model III was a significant computer in the history of computing. It was a commercial success and helped to popularize the use of personal computers in homes and small businesses. Its expandability and software support helped to make it a versatile computer that could be used for a variety of tasks.

Ultimately it paved the way for future generations of computers and helped to create a thriving ecosystem of software developers and users. It remains an important milestone in the history of computing and a testament to the power of affordable and easy-to-use personal computers.

References

1. TRS-80 Model III: The Radio Shack computer that launched a million hackers: https://arstechnica.com/features/2011/08/30-years-of-the-trs-80-model-iii/
2. TRS-80 Model III: https://en.wikipedia.org/wiki/TRS-80_Model_III
3. The TRS-80 Model III: https://www.old-computers.com/museum/computer.asp?c=1148
4. TRS-80 Model III: A History and Description: http://www.trs-80.org/trs-80-model-iii/
5. VisiCalc: https://en.wikipedia.org/wiki/VisiCalc

These sources provided information on the specifications, software, history, and impact of the TRS-80 Model III.

Be sure to check out another post on the TRS-80 Model III –> The TRS-80 Model III: Stephen King’s Favorite Computer

Thanks Everyone,

Shawn