Double lowres graphics?

[Dennis Jenkins <dennis@usb.com>]

Is it possible to manipulate any Apple II system into generating double
resolution low resolution graphics?  (ie, 80x40 or 80x48)?  I assume
that I'd have to write my own code to plot the pixels instead of calling
the routines built into Applesoft.

If it is possible, which models will it work on?  I'm primarily
interested in getting this to work on a IIe, IIgs and the IIe card in my
Mac LC-II.

If it is possible, then how would I access the AUX memory for
read/writes to 0x400-0x7ff.  I seem to remember reading about how to do
this from the book that came with the 80 column card.

If double low-res graphics are possible, I will write a library for the
CC65 compiler to do the normal graphics primitives that one would expect
(plot, peek (or SCRN() for the purists out there!), set color, cls, set
mode, etc...)

-- 
dennis@usb.com                           Universal Savings Bank.

The three most dangerous things are a programmer with a soldering
iron, a manager who codes, and a user who gets ideas.