JEMU - The Java Emulation Platform









JEMU is an Open Source Java Application designed to emulate various computer systems, with the ability to run as an Applet within a browser.


The JEMU architecture is based on CPU and Device classes, allowing individual devices to be encapsulated in Java classes for re-use in other systems (e.g. a 6845 CRTC controller is used in both the BBC Model B and the Amstrad CPC).


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Latest News


19-Feb-2007 Lots of new stuff in this version, including more accurate BBC cursor emulation, ** NEW ** ZX Spectrum emulation (not extremely accurate yet, but good enough for a few games to work). Improved VZ-200 and VZ-300 renderer with enough accuracy to handle split screen accurately. New source also available from the downloads section. Have fun!!
05-Aug-2006 Just 4 years since I did any updates. I've had a few new things in the pipeline, just waiting for an excuse to get them done. So here it is, the latest version, now with decent sound, better emulation for both the VZ and the CPC, and now emulation of the BBC Model B and Sinclair ZX80/81. There's still a glitch or two in the monitor emulation for the ZX80/81, visible in the supplied Space Invaders, but I think that's probably down to timing on the ZX interrupts or something. Still some keyboard bugs to iron out for the BBC in order to get Elite and Rocket Raid working properly, but Revs works perfectly, except for the cursor.. Does this show in the real game?

On another note, the new source is available for download, and this page should now work on either IE or Firefox, so long as you have Java 1.4 or above installed.
01-Jun-2002 Ok, finally got the CPC emulation up and running. I haven't done the AY (sound chip) emulation yet, just the IO ports for the CPC keyboard, that's why there's no sound with the CPC emulation. The home page (this page) has been modified to use JavaScript to get the available Computers and Games from the Applet itself. I think I've got the JavaScript working Ok now in both IE and Netscape 4.7. I haven't tested it with Netscape 6. Latest source is also available for download. Have fun.
23-May-2002 Sound output should now be working on the VZ emulation. Also added the Computer and Game selection boxes above. To run a game, press "Reset", select a game, then you may have to type RUN.
22-May-2002 The full web site is now up and running with the latest version of the emulator Applet on this page, and the latest source code available for download. The first computer to be emulated is the Dick Smith VZ-200 or VZ-300. This was my first computer, and is a Z80 based computer developed by Video Technologies. Double-click for the debugger.