Keyboard scanning and interface method and circuit

Details Keyboard scanning and interface method and circuit Keyboard scanning and interface method and circuit

1981-10-15

1985-02-26

Brigance, Gerald L.

Communications: electrical

Audible indication

Percussion-type sound producer

340365E, 340365R, G06F 302

Patent

active

045020388

ABSTRACT:
A method and apparatus is disclosed for allowing simultaneous depression or chording of a multiple number of keys on a keyboard coupled through an interface circuit to a computer operating system. An arbitrary association can be made to the chord which is distinct from the association made with its component keys. A dedicated processor system in the keyboard peripheral scans and stores in a dedicated memory the identity of all keys detected in the depressed state during the scan of the keyboard. For transmission to the computer operating system, each key depression detected during the scan is represented as an 8-bit binary component and the most significant bit of each binary component is set to the same one of the two permissible binary values, except for the most significant bit of the binary component representing the last depressed key detected during the scan of the keyboard. The most significant bit of that component is set to other of the two permissible binary values.

REFERENCES:
patent: 3778816 (1973-12-01), Cuccio
patent: 4106011 (1978-08-01), Melanson et al.
patent: 4145687 (1979-03-01), Masuda
patent: 4222038 (1980-09-01), Magerl
patent: 4277780 (1981-07-01), Sonderman et al.
patent: 4381502 (1983-04-01), Prame
IBM Technical Disclosure Bulletin, "Keyboard with Monopulse Key Sampling", Fisher & Pleshko, vol. 13, No. 1, Jun. 1970, pp. 72, 73.

Affiliated with

Also associated with

Rating

Keyboard scanning and interface method and circuit does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Keyboard scanning and interface method and circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Keyboard scanning and interface method and circuit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-518773