Posts tagged with “Steve Leininger”

The TRS‑80 Model I

The Radio Shack TRS‑80 Microcomputing System (catalog number 26-1001), later known as the TRS‑80 Model I, was introduced by Radio Shack on August 3, 1977. It made computer history as one of the first mass marketed, fully assembled microcomputers. The initial price was $599.95, which included a typewriter-style (not membrane) keyboard, monitor, and cassette recorder.


When the TRS‑80 Model I was introduced on August 3, 1977, it came with Level I BASIC, a 4K BASIC interpreter, in ROM. Level I BASIC was created by Steve Leininger, the designer of the TRS‑80, who based it on the public domain “Palo Alto Tiny BASIC” that Dr. Li-Chen Wang wrote in 1976.

But Radio Shack’s plan was always to upgrade to a more advanced Model I BASIC later. The very first TRS‑80 brochure said that “planned expansion includes an extended Radio Shack Level II BASIC.”

Why was the Model I uppercase only?

One of the biggest weaknesses of the TRS‑80 Model I was the lack of lowercase characters on the screen. Although that omission was hardly unique to the Model I (many computers at the time lacked lowercase, including the Apple II), it was still a notable limitation that affected many applications, especially word processing.

The two people most responsible for the Model I (originally known as the Radio Shack TRS‑80 Microcomputer System) were Don French and Steve Leininger.


When the TRS‑80 Model I was first released in 1977, the BASIC interpreter that Microsoft was writing, Level II BASIC, was still months away from completion. Instead the Model I originally shipped with a BASIC interpreter known as Level I BASIC.

Level I BASIC was based on “Palo Alto Tiny BASIC”, a 2K version of Tiny BASIC written by Dr. Li-Chen Wang for the May 1976 issue of Dr. Dobb’s Journal. Because Dr.

The Radio Shack “expansion box”

The TRS‑80 Model I was designed to allow for external expansion through what Steve Leininger described as an “expansion port” (the TRS‑80 card edge connector). Many people assumed that Radio Shack was developing a S-100 based expansion box to attach to the Model I. (The S-100 was a popular bus standard at the time.)

The first issue of the Radio Shack Microcomputer Newsletter in late 1977 contained a section answering some common questions about the new TRS‑80 computer.

Dr. Dobb’s Journal

Dr. Dobb’s Journal was one of the longest running microcomputer magazines, lasting 33 years in print form. It was first published in January 1976 as Dr. Dobb’s Journal of Computer Calisthenics & Orthodontia with the subtitle “Running Light Without Overbyte”. The title of the magazine was eventually shortened to Dr. Dobb’s Journal.

The name “Dr.