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Castle Iyonix

[Castle ]     [After Acorn ]


The Iyonix was the first 32-bit RISC OS computer, it comes with RISC OS 5 in Flash ROM so that it can be easily updated by upgrades distributed over the internet. The main features are:

Castle made a podule backplane  for the Iyonix to allow produles from RISC OS computers to be used with the Iyonix.

Manuals and documents



I bought my Iyonix in January 2003 and have been using it as my main computer ever since.

Here are some pictures:

Iyonix running RISC OS 5

Iyonix desktop running RISC OS 5.13

The main application running is WebWonder which I use to create Chris's Acorns. Also on the icon bar is Netsurf, used to check pages and FTPc used to upload the pages to the web server. On the left of the Icon bar the stacked disc icon is Access which I use to share public directories with my RiscPC and other Acorn computers. The Net icon is for Omniclient which I no longer use, but gives access to shared directories on my Windows 2003 server. To its right is the Sunfish icon which I now use for NFS access to the Windows 2003 shared directories. The last icon is for Aemulor.

Iyonix (front)

Iyonix (front)

At the top is the CDRW dirve with floppy disc drive below. To its right is the On switch. Below, on the left, is the Reset switch next to the power and HD activity LEDs and 2 x USB ports. At the bottom is the air inlet and the speaker is inside the case.

Iyonix back

 Iyonix (back)

The power supply is at the top with fan and on/off switch. Below the fan are the 2 Podule Bus openings (I don't have a backplane fitted, so no podules). Next to them are the 2 x serial ports, the network port and the audio sockets. At the bottom are the 4 PCI slots, one has the 2 x USB ports the other is the GeForce 2 MX video card.

Iyonix open

 Iyonix with the cover removed

The cabling for the power and IDE ribbon cables is a bit messy and hides much of the motherboard.

Iyonix motherboard

 Iyonix motherboard

On the top left side are the I/O ports. The large unmarked square chip is the Intel XScale 80321 CPU. The 512MB RAM SIMM is on the right side part hidden by the disc drives. The brown connector is for the 2 slot podule backplane (not fitted). To is right are the 2x IDE connectors and the floppy disc connector below them. On the left are the white PCI slots, The graphics card is in the bottom and the USB is in the top 64-bit slot. The UDMA card is in the back of the USB card slot.

Here is a HiRes picture of the Castle Iyonix motherboard .


Serial No.IYO1100939
Unique Identity00009950013A8
MotherboardCastle 8067660000001 Rev0.29
Motherboard Serial No.CTL2000-016.13.A8
CPUIntel IOP80321
CPU Clock600MHz
Memory512MB PC2100
Video ControllernVidia GeForce MX400
Floppy DiscSony MPF920-E
Disc Controlleron-board IDE
Hard Disc2 x Maxstor Diamond Plus 9 80GB
Network cardon-board
Network driverEtherK
OSRISC OS 5.13 (23-Feb-2007)
SICK v1.22
note 1
ARMSi v3.31H
note 1


1. Neither SICK v1.22 nor ARMSi will run on the Iyonix