Coded data generation or conversion – Bodily actuated code generator – Including keyboard or keypad
Patent
1988-01-29
1989-12-19
Yusko, Donald J.
Coded data generation or conversion
Bodily actuated code generator
Including keyboard or keypad
341 26, H03M 1100
Patent
active
048886009
ABSTRACT:
A matrix keyboard system for producing key codes in response to the actuation of key switches. The keyboard system includes ghost key condition detection. In the keyboard system, a group of parallel drive lines and a group of orthogonal parallel sense lines form a matrix, with a key switch being associated with each of the intersection points on the matrix. The drive lines are sequentially activated, and the actuation of a key switch along an activated drive line results in the coupling of a drive signal to the associated sense line. A ghost key condition arises when three of the four corners of a notional rectangle in the matrix contain an actuated key switch. The ghost key condition detector senses the presence of drive signals not only on the sense lines but also on the drive lines, with a ghost key condition being identified if a drive signal is sensed on two or more sense lines and two or more drive lines simultaneously.
REFERENCES:
patent: 3717871 (1973-02-01), Hatano et al.
patent: 3721976 (1973-03-01), Kuijsten
patent: 4106011 (1978-08-01), Melanson et al.
patent: 4231016 (1980-10-01), Ueda
patent: 4231024 (1980-10-01), Munetsugu
patent: 4326194 (1982-04-01), Pepe
patent: 4408184 (1983-10-01), Ishii
patent: 4420744 (1983-12-01), Jesson
patent: 4570154 (1986-02-01), Kinghorn et al.
patent: 4581603 (1988-04-01), Ingold et al.
patent: 4673933 (1987-06-01), Bauer
IBM Technical Disclosure Article by Bland and Bolt, vol. 27, No. 4A, Sep. 1984.
Anderson Frank E.
Gay Christopher J.
Hightower Scott A.
Luton Karen G.
International Business Machine Corp.
McArdle, Jr. John J.
Queen Tyrone
Yusko Donald J.
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