A Freeware Acorn Archimedes Emulator for Windows

RPCemu Spoon

This site is hosted by NETnorth

26th May 2010
All RPCemu development has moved to This is because the only branch still doing anything is the one with the silly name.

15th August 2009
Arculator 0.99 released.

Changes since 0.9/0.9a :
  • ICS IDE interface emulated, when new FDC is not in use
  • Improved IOC mapping, improvements on !PCem, NetBSD etc
  • ArculFS now read/write, and now ROM based
  • Sound improved a little
  • Can now disable all video borders
  • SWPB now works, also corrected SWP and MUL encoding - Fire & Ice now works
  • Return of FDI support
  • ADP protected disc image support
  • FDC improvements
  • High-res mono monitor emulation (1152x896)
  • A3010 joystick emulation

23rd March 2008
I've added a donation link on the left, explanations as to why are on the relevant page.

16th June 2007
RPCemu 0.7 released.

Changes since 0.6 :
  • New dynamic recompiler CPU core - between 2 and 4 times the speed of the interpreter, depending on machine, applications etc
  • RISC OS 4 now works properly with lazy task swapping on recompiler
  • CD-ROM support. .ISO images on all platforms, direct drive access on Windows and Linux
  • Now supports hard disc images above 2gb - the new limit is 32gb
  • New DOS port
  • Now compiles and (mostly) works on big-endian machines (eg PowerPC Macintosh)
  • Source code improved a bit

10th June 2007
Arculator 0.9a released.

Only change is that FDI support has been temporarily removed for licensing reasons.

6th February 2007
Arculator 0.9 released.

Changes since 0.8 :
  • Fixed ARM bugs - Bug Hunter now works, Phaethon no longer crashes on level 3
  • Fixed bug in 82c711 - Nebulus now works on new FDC
  • Fixed timing in modes 48/49
  • Various optimisations
  • Can now emulate ARM3 at 33mhz
  • Now emulates two hard discs
  • Removed software scaling options - improvements to hardware scaling mean these are not necessary anymore
  • Improved FDI support in new FDC - more games supported (eg Wolf 3d, SF3000 etc) with hard disc install
  • Mouse & keyboard shouldn't lock up in some stuff anymore
  • Some other fixes

26th December 2006
RPCemu 0.6 released.

Changes since 0.51 :
  • Working StrongARM emulation
  • Changed timing system, sound much more stable
  • Moved blitting to seperate thread, big speed boost in some stuff on dual core/hyperthreading CPUs
  • Optimisations to ARM + memory, speed boost between 10% and 25%
  • Fixed abort handling and MSR/MRS in 26-bit modes, more stuff now works, eg Ankh, Blu, Era, Reactivity, RISC OS 6
  • Changes to MMU permissions, ArmLinux now starts (but doesn't run yet)
  • Crash bug fixed in 32-bit colour
  • Can now alter video refresh rate from the default of 60hz
  • Better mouse support in Linux
  • Early GUI in Linux
  • Linux port now works on x86-64
  • Fullscreen mode (Windows only)

23rd October 2006
Arculator 0.8 released.

Changes since 0.7 :
  • Improved timing. Each model now performs much closer to the original machines (this means slower than previous versions)
  • Can now emulate MEMC page sizes other than 32k, so all memory configurations from 512k to 16 megs are now possible
  • Preliminary FDI support in 82c711 FDC
  • Better FDI support in WD1772 FDC
  • Fast disc emulation in 82c711 FDC
  • Bugfixes to video code. Man United Europe now looks better. Less flicker in Populous, Zarch etc
  • Keyboard/mouse fix, now doesn't freeze in Lemmings 2 and some other games
  • Fixed broken sound in Sensible Soccer and Xenon 2
  • Sound now in stereo
  • Some minor optimisations
  • Seperate ROM + CMOS files for Arthur, RISC OS 2, RISC OS 3 (old FDC) and RISC OS 3 (new FDC)
  • Tracked WD1772 hanging bug down to an incorrectly set CMOS bit! Now fixed

17th July 2006
RPCemu 0.51 released.

Just a quick release to fix some palette corruption issues.

28th June 2006

Uploaded a new archive for RPCemu 0.5 - the Windows build now works on non-AMD processors.

27th June 2006
RPCemu 0.5 released.

Changes since 0.4 :
  • Optimised flag emulation, outer loop, pipeline refilling - 30% speed increase
  • Couple of new instructions - latest Artworks Viewer now runs
  • Bugfix in IOMD timers - !ArcQuake and !SICK now work
  • Bugfix in MMU - large memory configurations work with all OSes now
  • Bugfix in dirty buffering - no more display artifacts
  • Windows interface slightly better
  • Added workaround for blitting issues on some graphics cards
  • Preliminary sound emulation (Windows 9x only)

9th May 2006
Arculator 0.7 released.

Changes since 0.6 :
  • Improved video code - display always centred correctly, multisync mode support (eg 640x480, 640x512 and 800x600), borders always drawn correctly (eg Zelanites)
  • Fixed bug with LDMxx!, !NewLook now works, Arthur desktop now works
  • Fixed bug in WD1772 FDC, disc writing now works again
  • Some improvements to ArculFS

28th April 2006
Arculator 0.6 released.

Changes since 0.5 :
  • Improved FDI support - many more games work
  • Improved video routines - new hardware scaling option, faster! Also more video modes implemented
  • ArculFS - read files from the Windows file system (read-only at the moment)
  • Can emulate ARM250

27th March 2006
RPCemu 0.4 released.

Changes since 0.3 :
  • Fixed stupid bug with flyback bit in IOMD control register - RiscOS 3.x nowstarts up correctly every single time (why did XXXX X work?)
  • Rewritten video emulation - now supports 16-bit & 32-bit colour, has correctly coloured cursor, some video acceleration, etc.
  • HostFS - allows access of the Windows filesystem from RISC OS
  • Now supports 2 hard discs
  • Now supports >16 megs RAM, and VRAM
  • Now licensed under the GPL
  • Preliminary Linux port, thanks to Peter Naulls

23rd January 2006
Arculator 0.5 released.

Changes since 0.4 :
  • Working 82c711 emulation. This allows high density disc access and avoids the hanging bug in 1772 emulation
  • Along with 82c711 emulation comes IDE hard disc emulation
  • Preliminary FDI support (1772 only)
  • Increased frequency of keyboard/mouse updates - mouse now much smoother
  • Slight optimisations to video

11th January 2006
RPCemu 0.3 released.

Changes since 0.2 :
  • Fixed up various 32-bit problems in the ARM core, XXXX XX X now works
  • IDE hard disc emulation
  • Fixed bugs in floppy emulation
  • Added emulation of ARM610 and ARM710
  • Low video resolutions (eg 320x480) now supported better
  • Faked sound interrupts (not enough for !Replay, but enough to fool Dune II)

4th January 2006
RPCemu 0.2 released.

Changes since 0.1 :
  • Ignored all unimplemented memory accesses, including Econet - RiscOS 3.7 now works
  • 70% speed increase
  • CMOS now actually saves
  • Cursor now correct colours
  • Less restrictive ROM loading

26th December 2005
RPCemu 0.1 released.

An early release, but a lot of software works already.

14th November 2005

New WIP page - for showing off new developments

12th October 2005
Arculator 0.4 released.

Changes since 0.35 :
  • Delayed IRQ by one instruction - Lemmings 2 now has sound.
  • Fast disc access.
  • Can disable scanline effect.

5th October 2005
Arculator 0.35 released.

Changes since 0.3 :
  • Fixed reading of R15 in some instructions - Nebulus now works.
  • Sound improved a bit.
  • Fixed RSC instruction (don't think it affects anything though).
  • Altered ARM timing.
  • Beginnings of new-style Arc emulation (HD floppies + IDE hard discs in theory, not working yet though).
  • Palette splits slightly more stable (Lotus 2).

22nd August 2005
Arculator 0.3 released.

Changes since 0.25 :
  • Much improved sound (filter still a bit off though).
  • Slight ARM optimisations - 10% speedup.
  • Bug fixes to VIDC and IOC - TCD Powerscroll and ARMageddon Megademo 3 now work.
  • Emulated prefetch - Elite now works (stupid protection).
  • Fixed stupid video mode 0 bug.
  • Replaced mouse hack with mouse capture technique.

22nd July 2005
Arculator 0.25 released.

Changes since 0.2 :
  • Disc emulation improved - can now access 720k DOS disc images, write to discs, and up to 4 drives now supported.
  • Arculator will now try to load a 2 meg file called 'rom.rom' before trying ic24-ic27.rom. This allows use of one-file ROM dumps, and Arthur, RiscOS 2 and ARM Linux ROM dumps (none of which really work, but never mind).
  • Slight changes to video emulation, Zelanites demo now looks okay.
  • Slight ARM optimisations.

I'm on the lookout for documentation on the ST-506 controller (HD63463) and/or the A540 SCSI controller. If anyone has documentation on these chips then please email me.

28th June 2005
Arculator 0.2 released.

Changes since 0.1 :
  • Added support for dual/quad MEMCs (8 and 16 megs of RAM).
  • ARM3 emulation.
  • ARM & video optimisations - 25% speed boost.
  • Rewritten video emulation - support midscreen palette/mode changes, correct cursor in 256 colour modes, better scrolling in hardware scrolling games, etc.
  • Reduced sound lag and improved sound overall.
  • Added fullscreen mode.

22nd May 2005
Arculator 0.1 released.

Changes since 0.09 :
  • Couple of CPU bugs fixed - Disc access now okay (hack no longer required), many more programs/games run.
  • Hack to work around other CPU bug.
  • Better video emulation - more modes, scrolling in James Pond and Chuck Rock, correct scrolling in supervisor.
  • New attempt at sound (quite poor).
  • Better mouse emulation.