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Texas instruments
TI-99/4a computer

In 1979, Texas Instruments introduces the TI-99/4a personal computer. 
With as little as just a basic console and television a TI99/4a was very functional and programs could be loaded VIA a cassette recorder or a ROM cartridge. The TI99/4a, which ran on a 16 bit TMS-9900 CPU at 3MHZ, the first ever 16-bit single-chip microprocessor used on an early Eighties home-computer.

It could easily be upgraded with various peripherials like the Expansion Box, which was a large case able to accommodate large expansion cards, and 5 1/4-inch floppy drives. 
A TI99/4a clone was even produced called a Geneve 9640 with a CPU running at 12MHZ and provided a vast improvement in speed, capabilities and video.

The TI-99/4a needed external power supply. 
The machine was unable to produce a TV video signal. You had to use the optional, external RF modulator which converted RGB monitor signals to TV compatible RF signals. 

  • TI 9900 16-bit microprocessor, running at 3 mhz
  • 16K of RAM 
  • Connects to a TV via an RF modulator (box on top left of computer)
  • Set of Joystick (left of computer)
  • Speech Synthesizer (right of computer)
  • 16 colors with graphic resolution of 256X192
  • Model = PHCOO4A
  • SN = 8152572 LTA1183

The back of the TI-99/4a

Texas Instruments is a large electronics company that has contributed considerably to the computer revolution. In 1958, a TI researcher named Jack Kilby demonstrated the first integrated circuit (IC), and in 1967, TI introduced the first handheld calculator.