HI Gary and all,
At 10:27 AM 10/3/98 -0700, you wrote:
To start things, I'd like to offer that I'm in
the process of recreating
a copy of Edmund Berkeley's "Simon" computer designed and built by him
in the 50's as a demonstration "show and tell" of how a "real"
computer
works. It's a collection of 100+ relays, two paper tape readers and
some blinkey lights. Version 1 was a "two bit" computer with the
ability to scale to 4 bits, while version 2 scaling to multiple precision
using a real CARRY! It's a small machine - "almost" a "laptop".
Right
now I'm collecting parts - specifically looking for the two paper tape
readers (solenoid operated - not motor driven - so if anyone out there
has one or two of these...)
For a reference to Simon, see the thirteen part series in Radio Electronics
magazine (US publication) from October 1950 through October 1951.
"Constructing Electronic Brains" by Edmund C. Berkeley and Robert A. Jensen.
There was also a cover article in Scientific American around that time -
sorry I don't have the issue handy with an overview of the project.
This sounds interesting. I will try to find the Radio Electronics articles
you mentioned. Can you describe the paper tape, was it 5 bits? Maybe
something else
could be used to simulate it, maybe a mechanical drum or a diode matrix =
rom if the number of bits isn't too large.
My first "computer" project was the game of "life" using TTL logic,
for
example a 7490 decade counter to count the cell's neighbors as other
counters moved through the 8 neighbor's x, y addresses.
-Dave