At Thursday 2002/08/01 15:20, you wrote:
A historical note - circa 1968 - Computer
Design magazine ran a series of articles on three-state hardware
logic.
Knuth called the three states flip-flop-flap, IIRC:-)
ternary logic (or base 3 systems) were indeed discussed c1968. The
biggest drawback to them from a hardware point, IIRC, was the difficulty
of making circuitry which would switch between any of the three states
without (in some cases) "passing through" the 3rd. There
were also all of the "off-color" comments about what to call
the equivalent of "bit" and such nonsense. The appeal, of
course, was an increase in density of computing elements (shorter word
sizes to hold the same magnitude of numbers). The most common
"word size" was 27 ternary-digits which gives numbers in the
±3,812,798,742,493
range.
My favorite argument was that you could build the system such that
truncation and rounding were the same operation (use the values -1, 0, 1
for the digits rather than the more traditional 0, 1, 2).
I think the thing that really shot it down tho, was trying to figure out
how to deal with the "boolean" operators. Instead of
having 16 (2^(2^2)) of them as we do in binary we'd have 19683
(3^(3^2)). Where would we come up with all the _names_???!!
Even more bizarre, IMO, than the radix 3 (ternary) logic systems were the
articles (same time frame) about using -2 as the radix.
--Beman
PGP RSA fingerprint = 4D20 EBF6 0101 B069 3817 8DBF C846
E47A
PGP D-H fingerprint = 98BC 65E3 1A19 43EC 3908 65B9 F755 E6F4 63BB
9D93
The five most dangerous words in the English language:
"There oughta be a law"