Patents Examined by M. G. Shehata
  • Keypad status reporting system
    Patent number: 5220601
    Abstract: A keypad status reporting system provides an indication over a serial bus as to which switch of a plurality of keypad switches is being selected by an operator wherein each keypad switch is coupled between a respective different pair of row and column conductors. The system generates parallel three-bit row and column addresses, combines the row and column addresses to form a parallel six-bit key code, and converts the key code to serial bits of data and places the serial bits of data onto a multiplexed bus in a predetermined channel.
    Type: Grant
    Filed: September 27, 1990
    Date of Patent: June 15, 1993
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Dale E. Gulick, Alan R. Hendrickson