Post by cb meeks
The Apple III (yes, 3) is a computer that I'd give my back teeth for. I own many Apple II's but I've always wanted an Apple III. Honestly, I don't really know why other than I don't have one.
That is reason enough. Before you give away your back teeth, you can
get somewhat of a feel by using the excellent MESS emulation of it -
including the excellent additions created by Eagan Ford called "Apple 3
Ready to Run":
But honestly, you need to touch one and work with it to really
Post by cb meeks
[yada yada yada]
I've read the SOS OS was pretty good. Being able to dynamically load device drivers into different areas of memory (something we take for granted these days).
Extended memory space using a standard 6502 architecture: swapping out
32k regions at a time:
Fully expanded, you had access to 512K (Apple only ever sold them with
256K, but Sun Remarketing took care of that). Pretty heady stuff for
the time. As a programmer used to the Apple II, having to know
different memory expansion schemes based on what expansion card was
plugged in... it's easy as pie to just have one architecture that swaps
in huge gobs of memory in one go.
It has a really nice BASIC language that makes it easy to extend with
"invokable" assembly modules - sort of like & functions in Applesoft.
BASIC isn't built-in, though. The ROM is really quite minimalist and
knows nothing more than how to do a self-check and then boot from the
built-in floppy disk. The plan was to get the firmware out of the way
and let the software take over. Apple forgot that lesson early in the
Mac days by burning lots of toolbox routines in ROM and later having to
patch them up with code off of disk after all. The downside to this
is... you can't do a ton with a /// without some floppy disks. The
upside is... you can boot SOS over the serial port with 77 bytes of code.
Device drivers are a dream. I've written a couple, so I can say beyond
the usual "it was the first loadable device driver architecture blah
blah blah" stuff that they're simple, straightforward, well documented,
and Apple gives you a template that any poorly trained monkey [i.e. me]
can follow and extend. It's a royal pain to do the configuration steps
to put one of those drivers on a boot disk, but given a rev or two of
SOS and the configuration software, that could easily be simplified.
The machine's untimely death stunted the ecosystem's growth, so we are
still saddled with some very early attempts to make things _possible_
before they had the opportunity to become _easy_.
And my favorite... variable-speed repeat of the cursor keys based on how
hard you pressed them. I can't tell you how cool it is to feel that
second <click> and have the cursor speed away. Nobody's done it before