The Edmund Digi-Comp I has been discussed here in the past, examine the
pictures at <
http://galena.tj.edu.inter.net/digicomp/> and see if they
look familiar.
Ward Griffiths
"the timid die just like the daring; and if you don't take the plunge then
you'll just take the fall" Michael Longcor
On Mon, 11 Jan 1999, Steve Robertson wrote:
> A little story:
>
> Seeing the tinkertoy computer reminds me of the mechanical "Computer" I got
> for Christmas when I was about 7 years old (1961..ish). It was a long long
> time ago and my memory could be a little distorted but, as I recall:
>
> It was made primarily of plastic and was about a foot long, 6 inches high,
> and 6 inches deep. This "toy" was built in horizontal layers or "planes"
> where each plane was one bit in the computer. The planes could slide either
> to the right or left to represent the logic states. If the plane was in the
> leftmost position, it represented a "0". If the plane was in the rightmost
> position, it represented a "1". I believe there were about 4 planes total.
>
> There was a "flag" (literally a flag) attached to the left end of each
> plane that provided the output. As the machine was cycled, the flags would
> raise and lower with the change in states.
>
> Along the rear of the computer there were a series of vertical wires that
> pushed the planes either to the right or to the left. These wires were the
> logic "gates" that drove the computer. As I recall there were about 8 of
> the wires (gates) in total.
>
> There were small projections from the rear of each plane that interacted
> with the wires (gates). To program the computer you placed small sections
> of a plastic soda straw, about 1" long, on some of the projections. The
> straws provided the input for each of the gates. If a straw was on one of
> the projections, it would interact with the wire (logical 1). If there was
> no straw on the projection, the wire would not touch the projection
> (logical 0).
>
> To operate the computer, the user would move a selected plane from one
> state to another. Any straws attached to the projections on that plane
> would push against the wires (gates) which in turn would push against the
> other planes in the machine. Some of the planes would change states, some
> would not.
>
> For each cycle of the machine, the user had to program in the next
> instruction. This meant moving around the straws on the back of the
> machine. Once the next instruction was loaded, the plane was slid back the
> other way. I never thought about it before but, this thing actually got two
> instructions per clock cycle.
>
> Max clock speed was about .01 CPS :-)
>
> The manual had detailed instructions for playing TIC-TAC-TOE and it
> actually worked. Unfortunately, it did not provide enough other examples
> so, I could never figure out how to make my own programs :-(
>
> I'm still fascinated by mechanical computers!
>
> Steve Robertson - QA Team Leader <steverob_at_hotoffice.com>
>
>
>
>
> > > So, where is the gag ? Just don't forget, the Z1 was entirely
> > > mechanical, to be powered by a crank (if necercary - of course they
> > > prefered th electric motor :).
> >
> > Gag? Mechanical computers are serious stuff, Hans. Like Danny Hillis'
> > tinker-toy tic-tic-toe machine:
> > http://www.yowza.com/classiccmp/toy/tinkertoy.jpg
> >
> > ObOT: BTW, does anybody know approximately when tit-tat-toe got renamed
> > tic-tac-toe? Or is a regional thing?
>
> Don't our "Queen's English" friends (uk and au) call it "naughts and
> crosses"?
>
>
>
>
Received on Mon Jan 11 1999 - 15:58:22 GMT
