posted by Michael Reed on Thu 7th Dec 2006 12:07 UTC

"Part I: Hardware, Continued; Emulation"

Current Workstations

Two RISCOS capable workstations are currently available for purchase.

The Processor

Both of these machines use current generation ARM processors that do not have a 26bit compatibility mode. This means that neither of these machines is backwards binary compatible with most older software. This might at first sound like a disaster but it's not as bad as it sounds. Firstly, as they run newer versions of RISCOS, older programs can be recompiled without a huge amount of recoding; nearly all current apps are released in a '32 bit clean' version. Secondly, a software emulator called Aemulator exists and this allows a lot of legacy software to run, unaltered and seamlessly on the RISC OS desktop. As the machines are much faster than the older generation, the performance of running an older app within the emulation framework is mostly acceptable.

The ARM processor used on these two workstations also suffers another problem: Lack of either multimedia extensions or a hardware FPU unit. So, in terms of raw multimedia processing or real-time 3d graphics power, the chip is less capable than, for example, a Pentium III processor of the same speed in MHz.

In their favour, the processor in either machine is passively cooled and draws a remarkably low amount of power.

Castle Iyonix - http://www.iyonix.com/

The Castle Iyonix has, as its basis, a custom ATX MB. The shipping configuration of the machine offers standard PCI slots, USB 2.0 and on-board IDE. The processor is a 600MHz Intel Xscale ARM processor. The graphics support is provided by either an NVIDIA Geforce 2 MX or FX5200 PCI graphics card. Unfortunately, only some of the available acceleration potential of this NVIDIA card is made available to RISCOS.

An experimental port of the BEOS Mesa Open GL driver has been completed so, it would seem that there may be some hope for 3d accelerated graphics on the platform in the future. See - http://www.simonrules.com/iyonixmesa/

Complete workstation packages start at 799 uk pounds.

A9Home - http://www.advantage6.com/products/A9home.html

Recent user review of the machine - http://www.iconbar.com/comments/news1090.html

In order to avoid direct competition with the already established Iyonix, Advantage 6 have innovated in a different direction. The A9Home uses an unusually compact form-factor. The website lists the case dimensions as: 6.6" x 4.1" x 2.1". That's considerably smaller than a Mac Mini for example.

The fact of the machine's compact nature has forced upon the designers the need for some compromise in terms of expansion and capability. Internally, the A9Home supports neither an optical drive or expansion via PCI slots. The computer has sockets for Ethernet networking and audio input and output. Further peripheral expansion is provided by USB slots. Another limitation is present here as the USB support is only 1.1 and there is no obvious way that this could ever be overcome. This means that devices such as pen drives and external CDROM drives can be connected to the machine but that they will operate at a greatly reduced speed. Internally, A9home is fitted with a 2.5'' 40meg hard drive.

Some users of early beta versions of the hardware were met with a surprise when they attempted to upgrade the DIMM memory in the single available slot as the supplied DIMM is not simply a memory module, it's a complete system on a chip, encompassing the ARM processor as well as 128MB of ram! To users of other platforms, the un-upgradable 128MB of RAM might sound like a large limitation, but due to the compact nature of the OS and the applications, 128MB is adequate for normal use.

Software Emulation

There exists a fully licenced commercial software emulation solution for running RISCOS called VARPC.

Review - http://www.drobe.co.uk/features/artifact939.html

This commercial software emulator runs on top of Windows. This emulator employs a JIT run time recompilation technique and for general use, on a current PC, it is capable of exceeding the performance of either of the hardware workstations.

By running RISCOS under software emulation, the user is giving up some of the benefits of RISCOS' ROM based nature. Firstly, RISCOS machines boot and up shut down a bit faster than Windows. Secondly, on real RISCOS hardware it is almost impossible to corrupt the OS as it exists within ROM. In the case of running an OS via emulation, the stability is only ever as good as the security of the host operating system. RISCOS may be somewhat free of malware problems but if Windows becomes unusable for any reason, RISCOS becomes inaccessible.

Table of contents
  1. "Introduction"
  2. "Part I: RISC OS Features"
  3. "Part I: RISC OS Features, Continued"
  4. "Part I: The OS Split; Hardware"
  5. "Part I: Hardware, Continued; Emulation"
  6. "Part II: Barriers to Adoption"
  7. "Part III: What Would It Take to Drag Me Back?"
  8. "Part III: PDA Port of RISC OS"
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