MITS Altair

MITS Altair. The MITS Altair 8800 is widely recognized as the catalyst for the microcomputer revolution of the mid-1970s. Introduced as a mail-order kit in the January 1975 issue of Popular Electronics, its affordable price and expandable design captured the imagination of electronics hobbyists and engineers. The machine's success directly inspired the founding of seminal companies like Microsoft and established the S-100 bus as an early industry standard.

History and development

The project was conceived by Ed Roberts (engineer), founder of Micro Instrumentation and Telemetry Systems in Albuquerque, New Mexico. Facing financial difficulties, Roberts bet the company on creating a low-cost computer built around the powerful new Intel 8080 microprocessor. The design, primarily by William Yates (engineer), was featured on the cover of Popular Electronics, edited by Les Solomon. The overwhelming demand, thousands of orders versus hundreds anticipated, created massive logistical challenges for the small company. This period saw early involvement from Paul Allen and Bill Gates, who developed a BASIC interpreter for the system, leading to the formation of Microsoft in Albuquerque. The success also attracted competition, notably from IMSAI, which cloned the S-100 bus.

Technical specifications

At its heart was the Intel 8080 central processing unit, an 8-bit chip running at 2 MHz. Standard memory was a mere 256 bytes of static RAM, expandable via plug-in cards to 64 KB. Input and output were accomplished solely through a front panel of toggle switches and LED indicators, with no built-in keyboard, monitor, or teleprinter. Data storage and loading were typically handled by an optional punched tape reader using Kansas City standard audio cassettes. The internal architecture was built around a 100-pin backplane, which became the de facto S-100 bus, used by many subsequent systems from companies like Cromemco and Vector Graphic.

Software and programming

Initially, all programming was done in machine code via the front-panel switches. The pivotal software development was Altair BASIC, the first product from Microsoft, then called Micro-Soft. This interpreter, developed by Paul Allen and Bill Gates with contributions from Monte Davidoff, made the machine accessible for more complex tasks. Other early languages included Tiny BASIC and a FORTRAN compiler. The CP/M operating system from Digital Research, created by Gary Kildall, later became the dominant disk operating system for S-100 bus machines. Early software distribution often occurred through hobbyist groups like the Homebrew Computer Club and publications such as Dr. Dobb's Journal.

Impact and legacy

The commercial success of this machine proved the existence of a viable market for personal computers, inspiring a wave of entrepreneurs and engineers. It directly led to the founding of Microsoft and provided a standard platform that fueled the growth of the S-100 bus industry. The cover story in Popular Electronics is frequently cited as the spark for the Homebrew Computer Club, whose members included Steve Wozniak and Steve Jobs, co-founders of Apple Computer. The open architecture encouraged a third-party expansion market, fostering companies like Processor Technology and Pertec Computer Corporation, which later purchased Micro Instrumentation and Telemetry Systems. Its design philosophy influenced nearly all early systems, including the Apple I, Commodore PET, and TRS-80.

Cultural significance

The machine attained an iconic status as the archetypal hobbyist computer, symbolizing the democratization of computing power. It featured prominently in early issues of magazines like Byte (magazine) and Creative Computing. The story of its development and the founding of Microsoft became a foundational myth of the Silicon Valley entrepreneurial spirit. It established the model of selling computer kits via mail order, which was later used by companies such as Heathkit. The device is permanently enshrined in the collection of the Smithsonian Institution and remains a celebrated artifact in the history of technology, representing the transition from mainframe computers to personal ownership.

Category:Microcomputers Category:American inventions Category:History of computing hardware