There are, of
course, many other features in the ROM; it's just a matter of
digging up the programming info. And (since you have such a late member of
the ][ series) there are also features in the hardware, such as double-
resolution text, low-res, and high-res modes, that the ROM was never updated
to handle.
How do you get at these modes? Are they in the IIgs, also?
The //e (I think it was the //e) first contained them. Every machine after
that, including the //gs, contains them. The //gs also has its own modes,
of course.
I think you can get at the double-res graphics modes from BASIC, but there
are no BASIC commands that directly support them. Also they use banked
memory. You can get at the 80 column text mode with PR#3.
Speaking of which, can you drive the IIgs graphics
chip and sound chip,
whatever they're called, from Applesoft?
I think I read on comp.sys.apple2 of demos that do that, but they were
written by Bruce Tognazzini or Paul Lutus or some other godlike figure. :)
-- Derek