Title:
CODE GENERATING KEYBOARD APPARATUS
United States Patent 3454717


Abstract:
1,060,878. Selective printing. CREED & CO. Ltd. June 18, 1965, No. 25871/65. Heading B6F. [Also in Division H4] A keyboard transmitter in which depression of a key provides a parallel signal which passes via a store to a distributer comprises means for automatically holding down a second key if that key is depressed when the store is full. In the embodiment described an actuated key enables an encoder which produces a 5-bit signal. This is gated to a first store whose output is gated to a second store which feeds the distributer. An arrangement of gates, toggles, and delays controls the gates and the resetting of the stores. This arrangement is fed by the Stop bit of the transmitted signal and by a signal from a circuit which checks the parallel signal from the encoder. If a second key is pressed when the first store is full, and if the encoder check is correct, the arrangement operates an electromagnet which holds down the second key until the first store is read out, the second key's 5-bit signal then passing from the encoder to the first store and the electromagnet being de-energized to release the key.



Inventors:
Peters, John William
Application Number:
US3454717DA
Publication Date:
07/08/1969
Filing Date:
05/17/1966
Assignee:
INT STANDARD ELECTRIC CORP
Primary Class:
Other Classes:
178/17R, 235/27, 341/32, 400/666
International Classes:
H04L13/16; (IPC1-7): H04L15/12
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