Welcome

Who are RISC OS Open Limited?

RISC OS Open Limited (ROOL) manages the source code to RISC OS. We are an organisation run on a largely voluntary basis. We also offer specialist professional services to anyone who is interested in developing products around the Arm architecture or RISC OS. You can find out more information about us here.

What is RISC OS?

RISC OS is a computer operating system designed in Cambridge, England by Acorn. First released in 1987, its origins can be traced back to the original team that developed the Arm microprocessor. RISC OS is owned by RISC OS Developments Ltd. You can find out more at sites such as riscos.info, The Icon Bar and RISCOSitory.

If you are new to RISC OS, you might want to look at the introductory pages in our wiki here.

Latest news

• Pi 400 coming in to land (23-Dec-2020)
• Development easier than A-B-C (30-Oct-2020)
• RISC OS 5.28 now available (24-Oct-2020)
• Charting our way (24-May-2020)

Recent changes in GitLab

• Pushed to branch master in Kernel (Jeffrey Lee) – Make supervisor stack inaccessible to user mode (16-Jan-2021)
• Pushed to branch master in FileSwitch (Timothy E Baldwin) – Add BASICTxt filetype (16-Jan-2021)
• Pushed to branch master in Kernel (Timothy E Baldwin) – Allow ZeroPage at any 64K aligned address (16-Jan-2021)
• Pushed to branch master in HdrSrc (ROOL) – Resync with allocations database (08-Jan-2021)