Warren Davis is correct in that the Gray code is a CLASS of binary codes.
The IEEE Standard Dictionary of Electical and Electronic Terms
defines the Gray Code as ALL binary codes in which sequential numbers
are represented by binary expressions, each of which differs from
the preceeding expression in one place only.

See also :Phister,M ; Logical Design of Digital Computers
and F. Gray, U.S. Patent No. 2632058, March 17,1953.

In the olden days (way before microcontrollers and even before DTL and
TTL
IC's) we used such tools as Truth Tables, Veitch Diagrams, Venn Diagrams
and pages of Boolean Algebra to design flip-flop based Gray Code
counters.
Now it requires nothing more than a PIC and a look-up table!

Roger Stevens
Ortemp, Inc

Contract Product Design
Tel. (707) 433-4459           FAX (707)433-4459


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What is a JOWETT JUPITER ?
Are there really Jowett Nuts ?
rogerlstevens@juno.com
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