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Imagine  a system  that waits  and toggles  on and off otherwise
separate audio-frequency oscillator circuits according to stored
memory. 

Thinking  about some electronics.   I would like to design  some
electronics,   not program  a high level  lisp in MCU  assembly.
According  to 1AM speculation,  here is what I'm thinking.   Our
various experts that be can offer some gentle corrections  of my
many mistakes. 

Target electronics : Some SRAM ; a small amount of static memory
that holds its value. 

A bunch  of DRAM, dynamic  memory.  In this case I think 4k is a
practical target amount.  Dynamic memory is very slow, since you
basically  have to seek through it until you reach  the position
you want (which was presumably recorded in SRAM), then wait some
number of clock cycles until the read hopefully  succeeded,  and
then  you only get one chance  to use the read  and rewrite  the
location.   This sucks, but those  rules  are the cost to having
lots of it. 

Addressing  4k of memory implies having at least 12 bit numbers.
If it plausibly took 4k cycles to do a dynamic memory readwrite,
operating  at 4kHz that's  one second a memory access.   I'm not
sure the frequencies  at which memory card and flip-flop options
can operate. 

On the clock  note, a clock.  A bunch of logic gates.   Buttons.
Blinkenlights. 

I  just want LISP function  circuits.   Then programs  are  data
written in lisp driving side-effects. CONS CAR CDR RPLACA RPLACD
INCF DECF COND NULL ZEROP NIL and I guess (INTEGER  (0 4096)). I
guess  a four bit function namespace  and 12 bit address / value
namespace  make up two eight bit bytes.  Add a notion of garbage
collection. 

This is much more primitive  than the 50s, though hypothetically
there are high performance cheap electronic components now. 

I know some people  were interested  in ACL2,  and others  LISPy
electronics  on principle.  I don't deeply grok the mathematical
principles involved right now, but I know enough to build my own
fancy laboratory inside my Land of Lisp text game framework. 

ACL2  is a computational  logic for an applicative   subset   of
common lisp. It has an extensive industry history. The key thing
is that with a bit of applicative  squinting and STOBJs, you can
just hack lisp into DEFTHMs.