A Successful Failure: The TI-99/4A Turns 40 #VintageComputing @TXInstruments @howtogeek

In June 1981, Texas Instruments released the TI-99/4A, a 16-bit home computer and gaming platform that became a huge cultural success in America after selling 2.8 million units, although it resulted in a business loss for TI. Forty years later, here’s what made it special.

After the 99/4 flopped in 1980, TI decided to try again. It went back to the drawing board and came up with the TI-99/4A (note the “A” in the name), which included the same 16 KB of RAM and 3 MHz TMS9900 CPU as its predecessor, but which also included a full-stroke keyboard, lowercase support, and graphics chip improvements.

Unlike the 99/4, the TI-99/4A didn’t need to ship with a dedicated color monitor. Without the expensive monitor, TI could cut the cost of its revised machine dramatically. The TI-99/4A launched in the U.S. in June of 1981 for $525 (equivalent to about $1,409 in 2021), which was about half the cost of an Apple II at the time. This price put it in the range of other consumer home computers, such as the Commodore VIC-20, TRS-80 Color Computer, and Atari 800.

The TI-99/4A included built-in TI BASIC programming language, and it shipped with nice manuals that taught computer novices (especially kids) basic programming concepts. For inexpensive data storage, you could buy a special cable that let you save or load programs with a standard cassette tape recorder.

Expansion on the TI-99/4A was a little weird. TI initially released several different “sidecar” modules for the 99/4 that plugged into a port on the right side of the computer. These modules included a disk drive controller, a 32K RAM expansion, an RS-232 interface, a speech synthesizer, and even a printer. If you plugged them all in at once, you got an ungainly peripheral train that barely fit on a desk.

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1 Comment

  1. ah that brings back memories, my first computer, I wanted an Apple II, but my parents bought me this (just like when my father bought a Betamax Video recorder, they were never tech savvy bless them).

    However I loved the the tunnel of Doom game and spend hours playing this dungeon crawling adventure (https://www.mobygames.com/game/ti-994a/tunnels-of-doom). I ultimately got my Apple IIe after selling this a couple of year later.

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