Nov 152017

A couple of years ago, RISC OS Open Ltd started building versions of RISC OS with “zero page relocation” – with the memory map changed such that the kernel’s workspace that started at the bottom of the addressable memory was moved to a higher location. This was an important step for security and stability, and for the future of the operating system.

However, it wasn’t ever going to happen without some casualties along the way; software that in some way tried to use or access certain information held in that workspace and which therefore found it no longer available. Aemulor, the 26-bit emulator that allows applications that are not yet fully 32-bit run on newer hardware, was one such casualty – and an important one at that.

The software was originally released to support the transition to 32-bit on the Iyonix – the first RISC OS computer to be released with a fully 32-bit version of the operating system. With a great deal of software yet to be made capable of running on a 32-bit platform, Aemulor was vital for users because it made it possible for them to run the applications they relied upon.

Even to this day, there is still software that is not yet 32-bit compatible. A particularly notable example of this is desktop publishing application Impression, for which work is underway. Although a lot of work has gone into the process of making Impression 32-bit, there is still a lot to be done, and in order to use it on a 32-bit platform, Aemulor is needed. Versions of Aemulor have been released for all of the main hardware platforms for which 32-bit versions of RISC OS have been released since the Iyonix, all the way up to Titanium-based computers – thus ensuring that Impression, and other applications like it, can still be used.

For anyone holding back from updating their version of RISC OS to a high-vector version – where the zero page workspace has been moved further up the memory map – there are now new builds of Aemulor available that should be compatible. However, please note that developer Adrian Lees warns that these are the latest development versions. While they should work, they may still need some work and changes before a more formal ‘stable’ release is made.

There are versions available, so the version you should download depends what platform you are using – and Adrian notes that a version of the software can be built to work on RPCEmu, and he aims to make this version available shortly.

Many thanks to Chris Hall for bringing this to my attention.