What (who) is RISC OS - definition

COMPUTER OPERATING SYSTEM

Riscos; Risc OS; RISC-OS; RISCOS; Acorn RISC OS

RISC OS

<operating system> (Reduced Instruction Set Computer Operating System) The operating system originally developed by {Acorn Computers} for their Archimedes family of {personal computers}. RISC OS replaced the Arthur operating system used on the first Archimedeses. It is written in ARM assembly code and distributed on ROM so it takes up no disk space and takes no time to load. It supports cooperative multitasking with memory management and includes a graphical user interface or "WIMP". It is written in a highly modular style and makes extensive use of vectors so it is easy to modify and extend by loading new modules in RAM. Many system calls (called "SWIs" - software interrupts) are available to application programmers and some of these are available as user comands via a built-in command-line interpreter. RISC OS also supported {outline fonts} when only bitmap fonts were available on most other platforms. Following the virtual demise of Acorn, development of RISC OS 4 was taken over by RISCOS Ltd on 1999-03-05 and released on 1999-07-01. Latest version: 4.39, as of 2004-09-21. (2004-09-21)

MIPS RISC/os

DISCONTINUED UNIX OPERATING SYSTEM DEVELOPED BY MIPS COMPUTER SYSTEMS, INC

RiscOS; MIPS OS; UMIPS; RISC/os; RISCwindows

RISC/os is a discontinued UNIX operating system developed by MIPS Computer Systems, Inc. from 1985 to 1992, for their computer workstations and servers, including such models as the MIPS M/120 server and MIPS Magnum workstation.

https://en.wikipedia.org/wiki/MIPS_RISC/os

History of RISC OS

ASPECT OF HISTORY

Arthur (operating system); Arthur (OS)

RISC OS, the computer operating system developed by Acorn Computers for their ARM-based Acorn Archimedes range, was originally released in 1987 as , soon followed by , and . The next version, , became and was completed and made available in April 1989.

https://en.wikipedia.org/wiki/History_of_RISC_OS

Wikipedia

RISC OS

RISC OS is a computer operating system originally designed by Acorn Computers Ltd in Cambridge, England. First released in 1987, it was designed to run on the ARM chipset, which Acorn had designed concurrently for use in its new line of Archimedes personal computers. RISC OS takes its name from the reduced instruction set computer (RISC) architecture it supports.

Between 1987 and 1998, RISC OS was included in every ARM-based Acorn computer model, including the Acorn Archimedes line, Acorn's R line (with RISC iX as a dual-boot option), RiscPC, A7000, and prototype models such as the Acorn NewsPad and Phoebe computer. A version of the OS, named NCOS, was used in Oracle Corporation's Network Computer and compatible systems.

After the break-up of Acorn in 1998, development of the OS was forked and continued separately by several companies, including RISCOS Ltd, Pace Micro Technology, and Castle Technology. Since then, it has been bundled with several ARM-based desktop computers such as the Iyonix PC and A9home. As of March 2017, the OS remains forked and is independently developed by RISCOS Ltd and the RISC OS Open community.

Most recent stable versions run on the ARMv3/ARMv4 RiscPC, the ARMv5 Iyonix, ARMv7 Cortex-A8 processors (such as that used in the BeagleBoard and Touch Book) and Cortex-A9 processors (such as that used in the PandaBoard) and the low-cost educational Raspberry Pi computer. SD card images have been released for downloading free of charge to Raspberry Pi 1, 2, 3, & 4 users with a full graphical user interface (GUI) version and a command-line interface only version (RISC OS Pico, at 3.8 MB).

https://en.wikipedia.org/wiki/RISC OS