1982 · Jupiter · UK · computer
Jupiter Ace
The home computer that booted into Forth instead of BASIC, and failed for it.
Mixed Trivial to run Needs a keyboard ▶ Watch on YouTube ↗
Image: Factor-h · CC BY-SA 3.0
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A 1982 machine from two engineers who had just left Sinclair, and a deliberate contrarian: where every rival booted into BASIC, the Ace booted into Forth. Elegant to programmers, baffling to everyone else, it failed commercially within a year.
It was built to be programmed, not played, and its handful of games barely register.
What it cost
about 13% of a month’s pay in 1982 · about $512 today
| UK launch list price (£89.95) |
£89.95 (1982)
British microcomputer uniquely programmed in Forth-79 instead of BASIC. |
|---|---|
| Typical street price | — No verified mass-market street price recorded yet. |
| Units sold | ≈5,000 estimate Around 5,000 units sold, highly prized by enthusiasts. |
Why it mattered
The Ace is the great contrarian of the British boom — a bet that ordinary buyers wanted Forth, not BASIC — and its swift failure is a neat lesson in knowing your market.
Emulating it today
| Emulators | EightyOne, MAME |
|---|---|
| Setup effort | Trivial to run (1 on this site's scale) |
| Controls | This is a computer-like platform: games may use a joystick or pad, but launching and configuring software often needs a keyboard. |
| Runs on a handheld | Yes |
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.
Firmware
This system needs no firmware file. Install an emulator, open a game, and it runs.
How many files you need: none to go and find. No separate firmware file is needed for an ordinary setup.
Firmware details checked 2026-08. Emulator requirements change — see Libretro 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
- 3D Maze 1983 maze
- Ace Invaders 1983 shooter
About as far as gaming got on a machine built to run Forth, not play.
The verdict
Fascinating to programmers curious about Forth; there is almost nothing to play.
This was a machine for tinkering, not gaming — emulate it to explore the language, not a library.
- Worth it if
- Players curious about acorn and the british micro scene 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 3/5 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
This page is 50% complete against the facts we try to record for every system. Gaps are shown as gaps.