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Chip Hall of Fame: Texas Instruments TMS9900

An ambitious failure, this processor powered the first 16-bit home computer

2 min read
TMS9900

TMS9900 chipPhoto:  Computer History Museum

TMS9900

Manufacturer: Texas Instruments

Category: Processors

Year: 1976

Rarely does a chip come so close to true greatness, only to see it slip from its grasp. The TMS 9900 from Texas Instruments had a lot going for it. By the early 1970s, TI had recognized that the nascent market for microprocessors—kicked off by the Intel 4004 in 1971—was going to drive a demand for more powerful chips than the 8-bit CPUs then on the market. The company had finally got a handle on the metal-oxide semiconductor technology displacing the early bipolar technology for making integrated circuit transistors. TI had the R&D resources and the marketing muscle to steal a march on the competition.

But the resulting 16-bit processor would miss its chance at the brass ring—being chosen to power the IBM Personal Computer. When “the TMS 9900 emerged in 1976, there were several problems,” wrote former TI Division Manager Walden C. Rhines in his dissection of the chip’s misfortunes for IEEE Spectrum. Two of the biggest: “The 9900 architecture, being the same as the TI minicomputer family, had only 16 bits of address space, the same as the 8-bit microprocessors of the day, and there was a strategic issue that competitors in the electronic equipment industry would be reluctant to endorse the architecture of a company that already had large computer, defense, and consumer product businesses.”

Instead the TMS9900 became the heart of the TI-99/4 and TI-99/4A microcomputers, earning them the distinction of having the first 16-bit CPUs in a home computer. The CPU ran fast too, with a clock speed of 3 megahertz, considerably faster than the 1- to 2-MHz clock speed of competitors like the Commodore 64. A price war with Commodore lead to TI-99/4A gaining significant market share, but at the cost of profitability. The computer might have survived to find a footing, but it was cursed by system design problems over and above any problems with the TMS9900, in addition to TI’s unwelcoming attitude to third-party software developers.

A number of successor chips followed, such as the TMS9995, which found use as an embedded controller, but the line never recovered from its initial stumbles: When it entered the PC market, TI ended up using Intel’s processors.

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The TMS9900 processor had a visionary purpose, but it was hobbled by trying to replicate a minicomputer architecture.

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The Godfather of South Korea’s Chip Industry

How Kim Choong-Ki helped the nation become a semiconductor superpower

15 min read
A man in a dark suit, bald with some grey hair, leans against a shiny blue wall, in which he is reflected.

Kim Choong-Ki, now an emeritus professor at Korea Advanced Institute of Science and Technology, was the first professor in South Korea to systematically teach semiconductor engineering.

Korea Academy of Science and Technology
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They were called “Kim’s Mafia.” Kim Choong-Ki himself wouldn’t have put it that way. But it was true what semiconductor engineers in South Korea whispered about his former students: They were everywhere.

Starting in the mid-1980s, as chip manufacturing in the country accelerated, engineers who had studied under Kim at Korea Advanced Institute of Science and Technology (KAIST) assumed top posts in the industry as well as coveted positions teaching or researching semiconductors at universities and government institutes. By the beginning of the 21st century, South Korea had become a dominant power in the global semiconductor market, meeting more than 60 percent of international demand for memory chips alone. Around the world, many of Kim’s protégés were lauded for their brilliant success in transforming the economy of a nation that had just started assembling radio sets in 1959 and was fabricating outdated memory chips in the early ’80s.

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