Acorn's Machine Operating System (MOS) or OS was a computer operating system used in the Acorn BBC computer range. It included support for four-channel sound and graphics, file system abstraction, and digital and analogue I/O including a daisy-chained fast expansion bus. The implementation was single-tasking, monolithic and non re-entrant.
Versions 0.10 to 1.20 were used on the BBC Micro, version 1.00 on the Electron, version 2 was used on the B+...
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Acorn's Machine Operating System (MOS) or OS was a computer operating system used in the Acorn BBC computer range. It included support for four-channel sound and graphics, file system abstraction, and digital and analogue I/O including a daisy-chained fast expansion bus. The implementation was single-tasking, monolithic and non re-entrant.
Versions 0.10 to 1.20 were used on the BBC Micro, version 1.00 on the Electron, version 2 was used on the B+, and versions 3 to 5 were used in the BBC Master Series range.
The final BBC computer, the BBC A3000, was 32-bit and ran RISC OS. Its operating system used portions of the Acorn MOS architecture and shared a number of characteristics (commands, VDU system) with the earlier 8-bit MOS.
Versions 0 and 1 of the MOS were 16KiB in size, written in 6502 machine code, and held in ROM on the motherboard. The upper quarter of the 16-bit address space (0xC000 to 0xFFFF) is reserved for its ROM code and I/O space.
Versions 2 to 5 were still restricted to...
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