Change Log

ArcEm 1.50.1 – 18th December 2015

• This is just a maintenance release for the RISC OS version of ArcEm. There are only two notable changes compared to 1.50:
• The released binary has been compiled with GCC 4.7.4, eliminating a null pointer deference bug that was present with the previous version of GCC/UnixLib
• Support has been added for the new screen modes introduced with RISC OS 5.21 (e.g. 64k colour modes and red/blue swapped modes), improving compatibility with new machines

ArcEm 1.50 – 16th December 2012

• New features
  • Addition of ports to Amiga OS 3 and OS 4.
  • Sound emulation.
  • Support for RAM sizes other than 4MB (512KB, 1MB, 2MB, 4MB, 8MB, 12MB & 16MB now supported).
  • ARM250 & ARM3 CPU emulation.
  • ArcEm clock set from host's clock, partial RTC support.
  • Extension ROM emulation, allowing support for the following new features when emulation RISC OS:
    • HostFS - A RISC OS filesystem to allow use of a directory on the Host Filing system as a virtual hard drive.
    • Mouse scroll wheel support.
    • Extra video modes, up to 1024x768 in 16 colours and 800x600 in 256 colours.
• Bug fixes/Improvements
  • Many performance tweaks and optimisations, resulting in a 5-6 times performance gain on ARM hosts. A 600MHz XScale can now achieve a level of performance roughly equivalent to an 8MHz ARM2. Similar performance gains can be seen on other low-power hosts.
  • Video emulation rewritten to provide accurate redraw and VSync timing, down to the scanline level.
  • Video emulation now supports upscaling and aspect ratio correction for rectangular pixel modes.
  • All hardware clocks/timers (IOC timers, video DMA, audio DMA, etc.) now run in real time, ensuring one second takes one second no matter how fast the host machine is.
  • Source code tidied a bit to remove redundant code, including support for emulation of 32bit processor modes (there are other, much better emulators for that!).
  • Source code converted to use C99 number types to aid portability.
  • Instruction prefetch now correctly emulated - ensures correct operation with self-modifying code and some forms of copy protection.
  • RISC OS version now 32bit compatible, and ARMv7-safe. Also much more useable with modern machines/LCD monitors as it no longer requires the host to be able to support Archimedes screen modes.
  • Windows version updated to build under Visual Studio 2010 (including Express edition).
  • Unix/X11 version now supports X servers that don't support XWarpPointer.

ArcEm 1.00 – 6th May 2002

• New manual and new SourceForge page. Other documentation deprecated.
• Added project files for MS VC++, and fix warnings provoked by it.
• Further split of windowing/non-windowing functionality to aid division of architecture-independent files.
• Windows version made independent from Cygwin.
• Windows support imported from eQRD version. Features brought inline with other versions, including icon change, and same format for choices file.
• Entirety of build warnings fixed under GCC, including those that appeared from turning on harsh warning flags.
• General tidying.
• Makefile rearranged so that default Unix builds are more sensible.

ArcEm 0.60 – 30th September 2001

• Support for running RISC OS, by Alex Macfarlane Smith and Peter Naulls
• Split of the windowing code, to allow independent development.
• Some small speed ups.
• Source code tidying and warning fixes.