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Archimedes
The 300 and 400 series, the A540, the A3000, and the A5000, A3010, A3020 and A4000: floppies, ST506 and IDE hard discs, and RISC OS 2 and 3 booting to the desktop.
Welcome to
MacArch
The Acorn Archimedes, on your Mac. Switch one on and use RISC OS, play your games, or wire up a classroom of them on Econet and watch them work together.
Game Library
A Top 25 of Archimedes classics, from Star Fighter 3000 and Zarch to Lemmings, with their box art. Get the discs from the Archimedes Archive and Play sets up the machine each one wants.
Network Studio
Archimedes on Econet with RISC OS's own network software and Acorn's Level 4 File Server. Share a network online, and MacBeeb's BBC Micros log on to your file server too.
A real Archimedes, down to the chips
MEMC, IOC and VIDC; the WD1772 or the A5000's 82C711; an ARM3's cache modelled for timing. The core is Swift, the screen is Metal, and a command line and an MCP server share the same core.
An ARM assembler
BBC BASIC V's assembler syntax as a file of its own: ADDEQS, SWIs by name, literal pools, INCLUDE and INCBIN.
And a debugger
Breakpoints in your source, stepping back as well as forward, the banked registers, memory, disassembly and watchpoints.
Debugging BBC BASIC V
A program's listing with breakpoints on its lines, stepping a statement at a time, its PROCs and FNs, and its variables to change.
Disc contents
ADFS floppies and hard discs in a window: drag files out to Finder with their RISC OS types, or drag Mac files in.
Hard discs from files
Make a formatted hard disc in one step, or one holding the files from ZIPs, folders and floppy images.
It works out your ROMs
Drop a ROM image, a set of chip files in any order, or a ZIP: MacArch finds the layout, checks it, and names the version.
RISC OS, yours or free
MacArch can't include RISC OS. If you own the ROMs, drop them on its welcome screen. If you don't, ArcLibre is a ROM restored from RISC OS's public source, and MacArch boots it to the desktop.
In a browser, too
MacArch's core builds as WebAssembly. The Archimedes on this site is that build, running ArcLibre on an A440/1. Click the screen to use its mouse.