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 professional services to anyone who is interested in developing commercial products using the ARM architecture and 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 Castle Technology Ltd. You can find out more at sites such as RISC OS Blog, 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: Headlines

• Did you notice? We changed everything (20-Aug-2018)
• Fruit of community effort ready to pick (29-May-2018)
• ROOL goes dutch at RISC OS eXperience 2018 (07-May-2018)
• RISC OS 5.24 stable is now available (23-Apr-2018)

Recent changes in CVS

• ROOL CVS: Improve detection of invalid/unsupported screen modes (16-Sep-2018)
• ROOL CVS: Allow selection of BBC gap modes via mode selector blocks (16-Sep-2018)
• ROOL CVS: Document the build options (16-Sep-2018)
• ROOL CVS: Add test case (15-Sep-2018)