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hardware key

hardware key

hardware key

Cutler-Hammer D-100 need physical hardware key on parallel port, any idea what's in connector?

RE: hardware key

Yes it does.  I took one apart several years ago and if I remember correctly it had a chip of some sort and a couple of resisters.

RE: hardware key

The Ic-s behavior can not be determined by test during the lifetime of the universe.

A combinatorial logic with N inputs may have 2^(2^N)
possible states. Any bit of memory is equivalent to
an input so N = number of (inputs + memorybits )

A 1Kbit memory will have two to the
1.27x 1,000,000,000,000,000,000,000,000,000,000 possibilities.

There is one way: autopsy the chip and measure under
microscope with micromanipulator -- a major project.


RE: hardware key

Some people's kids.... P-)

RE: hardware key

Sorry, an error: The 1.27e30 is the EXPONENT of 2
-- so I slightly nderestimated the complexity...


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