History of the TI-99/4A


By Casey V. Zigman
May 5, 2020

Before becoming renowned for their calculators, Texas Instrument was one of the major tech companies trying to make a name for themselves in the world of computing. The TI-99/4A computer did not manage to achieve this goal for the company; however, with the underperformance of the computer and the way it was advertised, Texas Instrument probably would not want it as the face of their computing industry. The TI-99/4A was an enhanced and upgraded version of the TI-99, featuring an improved keyboard and the capability to add any of numerous peripherals. A third party was contracted to assist in the assembly of a computer form entirely Texas Instrument components. The resulting model was given the codename “MOJO” 1 .  The peripherals were sold separately but included a variety of utility, ranging from a sound synthesizer to a printer or scanner. When all peripherals are added to the machine together, its length is extended to over 6 feet 2 . While not the most practical, the peripherals broadened the target audience of the computer. Initially the 99/4A was marketed towards gamers and those in the business industry through the preinstalled software, included hardware, and cartridge reader. The peripherals increase the computers overall use value as a home terminal. The computer possessed a very powerful microchip with respect to the other components of the computer 3 . This caused the computer to overheat and underperform after being used for too long. The competitive computing market at the time of its release contributed further to the acceptance of the TI-99/4A as a major flop by the company and public.


  1. Walden C. Rhines, “The Texas Instruments 99/4: World's First 16-Bit Home Commputer,” IEEE Spectrum: Technology, Engineering, and Science News, June 22, 2017, https://spectrum.ieee.org/tech-history/heroic-failures/the-texas-instruments-994-worlds-first-16bit-computer.

  2. "Texas Instruments TI-99/4A," Steve's Old Computer Museum, http://oldcomputers.net/ti994a.html.

  3. Michael Kilian, “The Many Faces of the TI 99/4A,” Microcomputing (January 1983), 76–80, https://doi.org/http://www.99er.net/files/manyface.pdf.