The Apple /// was supposed to capitalise on the unexpected soaraway success of the Apple ][ - more base memory and integrated components, colour graphics out of the box if you had the right monitor and similar expandability (though fewer slots because most of the things you needed slots for in the ][ were on-board now). It was released in late 1980 to, well, not much of a fanfare really.

You see, this was the first Apple machine designed by committee rather than engineers. Marketing had too much of a say in how the machine was going to look, so that coupled with Steve Jobs' insistence that the machine be fanless like its predecessor meant that it had to be put in a cast aluminium case so the entire case could be a heatsink.

The PSU was hermetically sealed inside its aluminium tomb and the only holes for ventilation were the expansion slots which got blocked as you added cards. Great.

The other issue was that the case design was finalised before the engineers had finished designing the motherboard, and the space they had available was less than they needed. This meant that untested methods and trace designs had to be used like half-width traces which was an emerging technology at the time. Early boards suffered short circuits because of this, in fact the first machines shipped were plagued with issues though these were corrected.

Cost was another factor, at release time it would relieve your wallet of $4340, though it's unclear as to whether this included the Monitor ///, a monochrome unit which was styled to fit snugly onto the top of the machine.

Also available was Apple's ProFile hard drive which was available in 5mb or 10mb sizes. This hooked up to a dedicated card in slot 4 (though it could be in any slot if you changed the driver) and was also designed to fit snugly between the machine and monitor.

OS wise the machine ran SOS, or Sophisticated Operating System which was so named because you could say 'Apple Sauce'. Those scamps eh. SOS introduced the idea of storage as a volume accessible via a path, so the internal floppy was .D1/ while the supported external Disk /// units were .D2/ to .D4/. If you had a ProFile its default path was .PROFILE/.

SOS also didn't give you a command line unless you were running Microsoft's rewritten Business BASIC, in which case you had to provide the SOS.DRIVERS file that was configured for the machine. This file was built using the SOS Utilities disk which also allowed you to reconfigure the drivers in use. Without BASIC you used a Program Chooser instead.

Since the Microsoft Softcard, a Z80 powered expansion card for CP/M access and Microsoft's first actual hardware product, had been a relative success on the Apple ][ they redesigned it for the /// and ported CP/M 2.2 for it along with MBASIC. It even supported the ProFile so having 5mb of space available for CP/M back in those days was ridiculous.

This machine came from Rich Kilpatrick waaaaay back in 2000, and back then I had zero idea how to drive it. Turned out that everything I'd learned since then I forgot, so I had to relearn stuff for the The Centre for Computing History's Z80 at 50 event recently where I took the machine and its new Softcard /// clone to show off. Part of writing this is for your entertainment and partly as an aide memoire for me :)