Free Jupiter Ace emulator for Windows

Jupiter Ace Emulator

Do you remember the Jupiter Ace ?

I cant say I did at the time it was released I was 9 years-old and entering the world of the ZX Spectrum and as with many people it passed me by, But now some 30 years on I wanted one to play with on one...but they are way out of my price range!... then I finally managed it, Wow You say!... hmm it wasn't that simple I had to write it first! ... the first Ace I saw running was this emulator ...after days of blood, sweat & tears, but mainly tears ( not the joyful sort )... I booted it for the first time and nothing.... all went dark! An entire black screen.. So I rebooted, checked the code, rebooted again and again... a lot more hours later unable to spot the bug... I rebooted the emulator and just left it on and a short time later a small white block appeared in the bottom left corner, hmm interesting ... so I pressed a key and it was ALIVE!!!! I had greatly over estimated the potential boot screen of the Jupiter Ace, it is somewhat more minimal to non existent ... and the little white square well that's the cursor! - Enjoy. More about the Jupiter Ace

Real JUPITER ACE Hardware

This wouldn't be very accurate emulation if we didn't test it against some real hardware and "we want accuracy, right?" - So after digging deep in our pockets - we found that wasn't enough.. after begging, digging deeper, no I mean really deep! We finally had access to a couple of real Ace's for testing, although the kids had no food, clothes or holidays, They'll enjoy the emulator too... { update: apparently not } well its all in the name of science of course... !

Our 3rd test machine will be built by hand, to the original PCB/ Circuit & Components of the ISSUE2 JUPITER ACE, We will add progress and info to the site when we can, its a very long process.

So here we are, For those that never owned, wanted, or now can't afford a real Jupiter Ace!
Plus those that paid out for their Ace and are too scared to use it or cant be bothered setting it up and taking over the TV or just don't have the an array of add-ons .. 3 Ram Packs, Real time - Debugger, Z80 Assembler, Instant Load & Save, Keyboard buffer, Convert a Text document to Forth, Access a hard drive tape library and load a tape in seconds, its for you too.

More about the emulator

Building a Jupiter Ace

Fisrt rough draft of experiences Building a Jupiter Ace


We need any old Jupiter Ace Hardware / Software / Information / Documents / Scans to preserve.. anything Cantrab related, Do you remember the company? Know someone that does? Just tell us your story or get it all from the loft, If you can help in anyway please do so, don't be shy!
contact us


Other related projects

It would be better to have a greater number of research machines but they don't grow on trees and are rarely offered for sale, So we are now attempting to build some using the original design.

Along with building the emulator we started a few other related projects and when ready will be released for public use - we are working hard... time and funds permitting.

Sinclair ZX Spectrum Emulator
Memotech MTX Emulator (Coming Soon)

If you like the site emulator or any of the tools or just the Jupiter Ace then please link to us,
and help us climb the

Thanks for reading, please if you can help out do so - Enjoy. Micro Emulator .net

Key Points

micro emulator

Free Jupiter Ace Emulator for Windows

It emulates all known Jupiter Ace behaviour, Inc. Z80 (doc'd and undoc'd), Screen, Memory access, Ram packs, Audio tape files, Tape deck emulation, Sound, Forth, Snapshot saving and loading and more ...

The Jupiter Ace emulator is an attempt to preserve this old micro for all to enjoy.


Microsoft Windows 7, Vista, XP
( XP requires microsoft .net framework )

NO install required, and NO registry garbage.

Download the
Latest Version 1.0.4247 Build: 37209 (5466)

we need your help!

Jupiter Ace Cassette Database

In order to maximise the database we need to find as many cassettes as possible, from unknown ones to ones known but we are unable to locate.

If you can help us with any old cassettes you may have in the loft you no longer want or know someone that has then please contact us and give them to a good home, If we can't get there in person we can get them collected by courier - please don't throw them!

Help by donating

Don't worry if you have no old hardware or software to donate, We greatfully accept funds via paypal to help us secure bits from others.

A big "THANK YOU!" to everyone the has donated, time, money, knowledge, tapes and hardware we are truly grateful - micro emulator .net Team.