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Home computer by Texas Instruments / From Wikipedia, the free encyclopedia

The TI-99/4 and TI-99/4A are home computers released by Texas Instruments in 1979 and 1981, respectively.[2] The TI-99 series competed against major home computers such as the Apple II, TRS-80, and the later Atari 400/800 series and VIC-20.[3]

Quick facts: Manufacturer, Release date, Introductory pric...
ManufacturerTexas Instruments
Release dateOctober 1979 (1979-10)
Introductory priceUS$1,150 (equivalent to $4,640 in 2022)
Units shipped~20,000
CPUTMS9900 @ 3 MHz
Quick facts: Manufacturer, Type, Release date, Introductor...
ManufacturerTexas Instruments
TypeHome computer
Release dateJune 1981 (1981-06)
Introductory priceUS$525 (equivalent to $1,690 in 2022)
DiscontinuedMarch 1984
Units shipped2.8 million[1]
Operating systemTI BASIC
CPUTMS9900 @ 3 MHz
Memory16 KB RAM
256 bytes scratchpad RAM
SoundTMS9919, later SN94624

Based on the Texas Instruments TMS9900 microprocessor originally used in minicomputers, the TI-99/4 was the first 16-bit home computer.[4] The associated video display controller provides color graphics and sprite support which were only comparable with those of the Atari 400 and 800 released a month after the TI-99/4.

The calculator-style keyboard of the TI-99/4 was cited as a weak point, and TI's reliance on ROM cartridges and their practice of limiting developer information to select third parties resulted in a lack of software for the system. The TI-99/4A was released in June 1981 to address some of these issues with a simplified internal design, full-travel keyboard, improved graphics, and a unique expansion system. At half the price of the original model, sales picked up significantly and TI supported the 4A with peripherals, including a speech synthesizer and a "Peripheral Expansion System" box to contain hardware add-ons. TI released developer information and tools, but the insistence on remaining sole publisher continued to starve the platform of software.[3]

The 1981 US launch of the TI-99/4A followed Commodore's VIC-20 by several months. Commodore CEO Jack Tramiel did not like TI's predatory pricing in the mid-1970s and retaliated with a price war by repeatedly lowering the price of the VIC-20 and forcing TI to do the same. By late 1982, TI was dominating the U.S. home computer market, shipping 5,000 computers a day from their factory in Lubbock, Texas.[3] By 1983, the 99/4A was selling at a loss for under US$100. Even with the increased user base created by the heavy discounts, Texas Instruments lost US$330 million in the third quarter of 1983[5] and announced the discontinuation of the TI-99/4A in October 1983. Production ended in March 1984.[3]

The TI-99/4 was intended to fit in the middle of a planned range of TI-99 computers, none of which were released, but prototypes and documentation have been found after the TI-99/4A was discontinued.[citation needed]

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