As the history committee chair of the IEEE Lone Star Section, in San Antonio, Texas, I am responsible for documenting, preserving, and raising the visibility of technologies developed in the local area. One such technology is the Datapoint 2200, a programmable terminal that laid the foundation for the personal computer revolution. Launched in 1970 by Computer Terminal Corp. (CTC) in San Antonio, the machine played a significant role in the early days of microcomputers. The pioneering system integrated a CPU, memory, and input/output devices into a single unit, making it a compact, self-contained device.

Apple, IBM, and other companies are often associated with the popularization of PCs; we must not overlook the groundbreaking innovations introduced by the Datapoint. The machine might have faded from memory, but its influence on the evolution of computing technology cannot be denied. The IEEE Region 5 life members committee honored the machine in 2022 with its Stepping Stone Award, but I would like to make more members aware of the innovations introduced by the machine’s design.

From mainframes to microcomputers

Before the personal computer, there were mainframe computers. The colossal machines, with their bulky, green monitors housed in meticulously cooled rooms, epitomized the forefront of technology at the time. I was fortunate to work with mainframes during my second year as an electrical engineering student in the United Arab Emirates University at Al Ain, Abu Dhabi, in 1986. The machines occupied entire rooms, dwarfing the personal computers we are familiar with today. Accessing the mainframes involved working with text-based terminals that lacked graphical interfaces and had limited capabilities.

Those relatively diminutive terminals that interfaced with the machines often provided a touch of amusement for the students. The mainframe rooms served as social places, fostering interactions, collaborations, and friendly competitions.

Operating the terminals required mastering specific commands and coding languages. The process of submitting computing jobs and waiting for results without immediate feedback could be simultaneously amusing and frustrating. Students often humorously referred to the “black hole,” where their jobs seemed to vanish until the results materialized. Decoding enigmatic error messages became a challenge, yet students found joy in deciphering them and sharing amusing examples.

Despite mainframes’ power, they had restricted processing capabilities and memory compared with today’s computers.

The introduction of personal computers during my senior year was a game-changer. Little did I know that it would eventually lead me to San Antonio, Texas, birthplace of the PC, where I would begin a new chapter of my life.

The first PC

In San Antonio, a group of visionary engineers from NASA founded CTC with the goal of revolutionizing desktop computing. They introduced the Datapoint 3300 as a replacement for Teletype terminals. Led by Phil Ray and Gus Roche, the company later built the first personal desktop computer, the Datapoint 2200. They also developed LAN technology and aimed to replace traditional office equipment with electronic devices operable from a single terminal.

The Datapoint 2200 introduced several design elements that later were adopted by other computer manufacturers. It was one of the first computers to use a keyboard similar to a typewriter’s, and a monitor for user interaction—which became standard input and output devices for personal computers. They set a precedent for user-friendly computer interfaces. The machine also had cassette tape drives for storage, predecessors of disk drives. The computer had options for networking, modems, interfaces, printers, and a card reader.

It used different memory sizes and employed an 8-bit processor architecture. The Datapoint’s CPU was initially intended to be a custom chip, which eventually came to be known as the microprocessor. At the time, no such chips existed, so CTC contracted with Intel to produce one. That chip was the Intel 8008, which evolved into the Intel 8080. Introduced in 1974, the 8080 formed the basis for small computers, according to an entry about early microprocessors in the Engineering and Technology History Wiki.

Those first 8-bit microprocessors are celebrating their 50th anniversary this year.

The 2200 was primarily marketed for business use, and its introduction helped accelerate the adoption of computer systems in a number of industries, according to Lamont Wood, author of Datapoint: The Lost Story of the Texans Who Invented the Personal Computer Revolution.

The machine popularized the concept of computer terminals, which allowed multiple users to access a central computer system remotely, Wood wrote. It also introduced the idea of a terminal as a means of interaction with a central computer, enabling users to input commands and receive output.

The concept laid the groundwork for the development of networking and distributed computing. It eventually led to the creation of LANs and wide-area networks, enabling the sharing of resources and information across organizations. The concept of computer terminals influenced the development of modern networking technologies including the Internet, Wood pointed out.

How Datapoint inspired Apple and IBM

Although the Datapoint 2200 was not a consumer-oriented computer, its design principles and influence played a role in the development of personal computers. Its compact, self-contained nature demonstrated the feasibility and potential of such machines.

The Datapoint sparked the imagination of researchers and entrepreneurs, leading to the widespread availability of personal computers.

Here are a few examples of how manufacturers built upon the foundation laid by the Datapoint 2200:

Apple drew inspiration from early microcomputers. The Apple II, introduced in 1977, was one of the first successful personal computers. It incorporated a keyboard, a monitor, and a cassette tape interface for storage, similar to the Datapoint 2200. In 1984 Apple introduced the Macintosh, which featured a graphical user interface and a mouse, revolutionizing the way users interacted with computers.

IBM entered the personal computer market in 1981. Its PC also was influenced by the design principles of microcomputers. The machine featured an open architecture, allowing for easy expansion and customization. The PC’s success established it as a standard in the industry.

Microsoft played a crucial role in software development for early microcomputers. Its MS-DOS provided a standardized platform for software development and was compatible with the IBM PC and other microcomputers. The operating system helped establish Microsoft as a dominant player in the software industry.

Commodore International, a prominent computer manufacturer in the 1980s, released the Commodore 64 in 1982. It was a successful microcomputer that built upon the concepts of the Datapoint 2200 and other early machines. The Commodore 64 featured an integrated keyboard, color graphics, and sound capabilities, making it a popular choice for gaming and home computing.

Xerox made significant contributions to the advancement of computing interfaces. Its Alto, developed in 1973, introduced the concept of a graphical user interface, with windows, icons, and a mouse for interaction. Although the Alto was not a commercial success, its influence was substantial, and it helped lay the groundwork for GUI-based systems including the Macintosh and Microsoft Windows.

The Datapoint 2200 deserves to be remembered for its contributions to computer history.

The San Antonio Museum of Science and Technology possesses a collection of Datapoint computers, including the original prototypes. The museum also houses a library of archival materials about the machine.

This article has been updated from an earlier version.