Web site:
Origin: USA
Category: embedded
Desktop environment: CLI
Architecture: Motorola 86000
Based on: Darwin
Wikipedia: A/ROSE
Media: Install
The last version | Released: 1988 (?)
A/ROSE (Apple Real-time Operating System Environment) – a small embedded operating system that runs on Apple Computer’s “Macintosh Coprocessor Platform”, an expansion card for the Macintosh.
A/ROSE is very small at 28 KB, with a 6 KB kernel. A/ROSE supports pre-emptive multitasking with round-robin scheduling of tasks, with a 110 microsecond context switch time and only 20 microseconds of latency (guaranteed interrupt response time). The system’s task is primarily to move data around and start and stop tasks on the cards, and the entire API contains only ten calls.
The idea was to offer a single “overdesigned” hardware platform on which third-party vendors could build practically any product, reducing the otherwise heavy workload of developing a NuBus-based expansion card. However, the MCP cards were expensive, limiting the appeal of the concept. A/ROSE had very little use, apparently limited solely to Apple’s own networking cards for serial I/O, Ethernet, Token Ring, and Twinax. GreenSpring Computers developed the RM1260, which is an IndustryPack (IP) carrier card with a 68000 CPU running A/ROSE and is intended for the data acquisition market.
A/ROSE and the MCP originated in August 1987 during the development of the Macintosh II. While working on various networking products for the new system, the developers realized that the existing classic Mac OS would make any “serious” card difficult to create, due to large latencies and the difficulty of writing complex device drivers. Their solution was to make an “intelligent” NuBus card that was essentially an entire computer on a card, containing its own Motorola 68000 processor, working space in RAM mirrored in the main system, and its own basic operating system. The first version of the system was ready for use in February 1988.
A/ROSE was internally called MR-DOS (Multitasking Realtime Distributed Operating System), but Microsoft (the developer of MS-DOS) did not appreciate the name and put pressure on Apple to change it. Eric M. Trehus, a QA engineer on the Token Ring card running A/ROSE reportedly said “A/ROSE by any other name is still MR-DOS.”
Source: Wikipedia; License: Creative Commons Attribution-ShareAlike 4.0.
