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Re: What is the quintessential Apple II?
Alex Freed wrote:
"Michael J. Mahon" <mjmahon@aol.com> wrote in message
z9KdnRi4dbi39D7YnZ2dnUVZ_t2tnZ2d@comcast.com">news:z9KdnRi4dbi39D7YnZ2dnUVZ_t2tnZ2d@comcast.com...
This is what leaves a bad taste in my mouth when I think about adding
an interface to the Apple II by attaching 10x the number of transistors
as there are in the *whole* Apple II! The fact that they're all packed
into a modern chip or two doesn't make the sense of disproportion go
away...
My understanding of the A2 design philosophy is quite different.
IMHO A2 is all about using inexpensive off-the-shelf parts in a smart way,
not using parts with a minimal number of transistors.
For example the PAL encoder on the European Apple (that I never saw,
but read about). Uses a DECODER chip to ENCODE PAL color just
because it was cheap and plentiful. It is possible to make an encoder with
ZERO transistors using just coils and diodes, but why bother if the chip is
there?
These days the same logic can be applied to say using a $3 ARM uC with
tons of transistors inside to say control a disk drive.
I understand perfectly, Alex.
I've realized that my appreciation for Apple II implementations is
not just a matter of their functionality (what they do), but design
(how they do it).
Compatibility concerns depend only on the *function* of the box, without
considering what's inside the box and how it achieves its function.
There was nothing particularly innovative about attaching a floppy drive
to a microcomputer, but doing the data separation with a PROM and a
shift register combined with software, eschewing the usual integrated
controller chip, was brilliant.
The fact that an 8-pin microcontroller is often now a better overall
solution than a 555 timer doesn't alter the fact that the timer is
a much simpler device, and a much lower level of technology.
Even when cannons are half the price of mousetraps, using a cannon
to shoot a mouse is "not very sportsmanlike". ;-)
My engineering esthetic, when applied to the Apple II, comes to a
similar conclusion, though I readily embrace newer technology in
other design arenas.
I note that my taste is tempered by pragmatism, since I wouldn't give
up my Zip Chip, and it is much more complex than the 65C02 it replaces.
;-)
It's not at all surprising that new design work for the Apple II tends
to use the same tools and methods that are used for all new design work.
After all, people design with what they are used to.
I do regret sometimes that we are forgetting how to design with the
older technology, and, in particular, within the constraints of older
technology (like the Apple ][).
Just the other day I was thinking about how wonderful the design of
the vacuum tube timing ramp generator called the phantastron was--a
beautiful use of negative feedback before gain was free and negative
feedback was everywhere. And now, only a few old radar engineers
would even know it existed...
Hmmm...way too much nostalgia--back to coding the 6502. Oh, wait--
that *is* nostalgia! ;-)
-michael
NadaNet networking for Apple II computers!
Home page: http://members.aol.com/MJMahon/
"The wastebasket is our most important design
tool--and it's seriously underused."