How to create a native RISC OS CD on a PC

This document describes a method to create a true native RISC OS CD on a PC. At this moment it is only tested on my own Acorn R260. The only disadvantage I can think of is that the CD is not in ISO 9660 format. So you can only use it on a computer with RISC OS.

The Acorn side

I use a DSAS-3540 (IBM) SCSI harddisc and a Toshiba single speed CD ROM drive connected to a AKA32 (Acorn) SCSI expansion card. The computer is an Acorn R260. The DSAS-3540 is hard to get working with an AKA32. I only got it working as device 0 and with the following jumper settings:

See DALS-3540 (540 MB) specifications (PDF) for more information.

The PC side

I create the CD with DISK2CD.EXE on a PC. This program is freeware and part of the DAO package which can be downloaded at The program copies a SCSI harddisc block-by-block to the CD and can be used to create native CDs.

Before connecting the harddisc to the PC make sure that you change the SCSI ID to, for example 2. The SCSI adaptor uses in most cases ID 0. I just move the "Disable unit attention" jumper to pin 1 (ID = 2). I use a P133 with an Adaptec AHA-2920 and a Philips CDD 2600 writer.

You can check your configuration with:


See DISK2CD /? for a description of the other options.

Using the CD ROM

You can use !MoFS, which can be downloaded as magfs.arc to read the CD with a SCSI CD ROM drive. Just change the SCSI ID in the !Run file.