1981 · Texas Instruments · US · computer
Texas Instruments TI-99/4A
The TI-99/4A was an engineering powerhouse: a true 16-bit microcomputer wrapped in brushed aluminum with the legendary TMS9918A video chip and robotic…
A curiosity Easy to run Needs a keyboard ▶ Watch on YouTube ↗
The TI-99/4A was an engineering powerhouse: a true 16-bit microcomputer wrapped in brushed aluminum with the legendary TMS9918A video chip and robotic speech synthesis add-on module.
In 1982–1983, Texas Instruments and Commodore engaged in a brutal price war that drove computer prices under $150. Although TI sold nearly 3 million units, they lost hundreds of millions of dollars and exited the home computer market in October 1983.
Under the hood
- CPU
- Texas Instruments TMS9900 (True 16-bit CPU) @ 3.0 MHz
- Sound chip
- TMS9919 (3 sound channels + 1 white noise) + TMS5200 Speech Synthesizer
- Graphics
- TMS9918A VDP, 256 × 192, 16 colors, 32 hardware sprites
- Media
- Solid State Software Cartridges & Cassette / Floppy
What it cost
about 13% of a month’s pay in 1983 · about $469 today
| US launch list price ($525) |
$525 (1981)
about half a month’s pay · about $1,812 in today's money |
|---|---|
| Mass-market price ($149 after $100 rebate) |
$149 (1983)
Slashed during the 1982–1983 home computer price war against Commodore. |
| Units sold | ≈2,800,000 estimate Over 2.8 million units sold before TI withdrew from home computing. |
Why it mattered
In 1982–1983, Texas Instruments and Commodore engaged in a brutal price war that drove computer prices under $150. Although TI sold nearly 3 million units, they lost hundreds of millions of dollars and exited the home computer market in October 1983.
Emulating it today
| Emulators | Classic99 (Superb Windows/Wine standalone), MAME (ti99_4a), js99er |
|---|---|
| Setup effort | Easy to run (3.5 on this site's scale) |
| Controls | The original software assumes a keyboard. A desktop setup feels natural; on a handheld, map common keys and keep an on-screen keyboard available. |
| Runs on a handheld | Yes |
Uses a 16-bit TMS9900 CPU with complex memory paging. Emulators require TI system ROMs (`994a.rom`, `ti-disk.rom`) and virtual floppy or solid-state cartridge images. The emulator names above are starting points, not a promise that every title or accessory behaves identically. Computer platforms usually add model selection, disk handling and keyboard setup even when CPU emulation itself is mature.
TI-99/4A System ROM & GROM (994a.rom, 994agrom.rom)
The Texas Instruments TI-99/4A relies on internal system ROM (8 KB) and proprietary Graphics Read-Only Memory (GROM, 24 KB) chips that contain TI's GPL interpreter, system monitor, and character tables. Emulators require dumps of both chips.
How many files you need: 2. Two files (or ti99_4a.zip in MAME): system ROM (8 KB) and system GROM (24 KB).
Where it stands legally: Copyrighted by Texas Instruments; available legitimately in Classic99 by permission.
Firmware details checked 2026-08. Emulator requirements change — see Classic99 TI-99/4A Documentation for the current list.
Where the software is
TOSEC catalogues computer disks and tapes broadly, including many revisions. It is useful for preservation, while a smaller curated selection is usually easier to play.
Copyright: Commercial software remains copyrighted unless its owner explicitly released or relicensed it. Homebrew, public-domain programs and current reissues should be treated separately from abandoned commercial titles.
This site names preservation projects and explains what they are. It does not link to ROM downloads.
Where to start
- Parsec Side-scrolling Shooter
The definitive TI-99 game with synthesized robotic speech warnings ("Alert! Alien craft approaching!").
- Tunnels of Doom RPG / Dungeon Crawler
Groundbreaking tactical party-based dungeon crawler with custom quest modules.
- TI Invaders Fixed Shooter
One of the smoothest, most colorful Space Invaders home conversions.
- Alpiner Action Mountain Climber
Climb real world peaks while dodging falling rocks and trees.
- Munch Man Maze Action
Pac-Man reimagined where you lay down chains instead of eating dots.
- Hunt the Wumpus Text / Logic Adventure
Classic tactical cave exploration with hazards and arrow shooting.
The verdict
Beautiful brushed aluminum chassis and distinct TI speech synthesizer add-on. Games like Parsec and TI Extended BASIC are fun for retro tech buffs, but third-party library was restricted.
The strongest software can be rewarding, but original controls and setup assumptions may matter more than screenshots suggest.
- Worth it if
- Players curious about educational machines, oddities and fantasy consoles and willing to learn how the original machine worked.
- Not for
- Anyone who wants a large, instantly accessible library and no model, firmware or control decisions.
Scored 2/5 for fun today and 3/5 for historical importance. Those two scores decide the label at the top — a machine can matter enormously and still be no fun.
Read more & watch
- Emulation General Wiki
- ▶ YouTube: Watch Texas Instruments TI-99/4A retrospectives, demos & reviews ↗
This page is 75% complete against the facts we try to record for every system. Gaps are shown as gaps.