Woz was apparently able to save a few chips by using a convoluted (at least to software) layout. It's exactly this reason that the book quoted by the OP was such a watershed moment for all of us kids trying to wrap our adolescent brains around the Apple II's internals. I still have my copy, held together with packing tape.

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

Part of that was practically reusing the character generator logic to do the hi-res screen, though this wasn't unusual either (compare with the TMS9918A).

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Machine room: http://www.floodgap.com/etc/machines.html

I believe that I have a low-mileage example stashed in my attic somewhere. If you PM me your snail mail address, I'll try to dig it up and send it to you, no charge, as a thank you for your contributions to the community.

Garth received my original BYTE Forth issue a few years ago, and seemed genuinely pleased to have the real Aug 1980 issue, yellowed and fragile as it was. Ethan Blanton on Ed's Retro Computing Forum received my original Applesoft Tutorial #A2L0018 and was similarly pleased. cbmeeks is the proud new owner of my Franklin Ace 2200, with detached keyboard, manual, and a few floppies, but it had suffered some rough handling, and was going to need a bunch of help before powering up. Charlie Gibbs received my early paperback edition of Heinlein's Expanded Universe.

My attic holds literally tons of stuff like that, and it pains me to realize that it's all slowly deteriorating without anyone to appreciate it before it inevitably ends up in a landfill after my passing (hopefully a few decades or more from now, but who knows?)

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Got a kilobyte lying fallow in your 65xx's memory map? Sprinkle some VTL02C on it and see how it grows on you!

Mike B. (about me) (learning how to github)