×

Point of sale system having backup file device

  • US 5,313,664 A
  • Filed: 11/20/1992
  • Issued: 05/17/1994
  • Est. Priority Date: 03/25/1988
  • Status: Expired due to Term
First Claim
Patent Images

1. A point of sale system, comprising:

  • a plurality of satellite terminals positioned for inputting data on sold goods;

    a master terminal coupled to said plurality of satellite terminals to transmit and to receive said data;

    file control means for transmitting and receiving said data coupled with said master terminal and with said plurality of satellite terminals, said file control means including a point of sale data file and an associated file control section, said file control section updating said point of sale data file when sequentially polling said master terminal and said plurality of satellite terminals during predetermined time intervals in a cycle of operation, the updating of said point of sale data file by said file control section being in response to requests from said master terminals and said plurality of satellite terminals and said file control section controlling communication of said data with said plurality of satellite terminals and confirming the transmitting and receiving of said data with said plurality of satellite terminals from which the requests are made within a predetermined interval of time; and

    said file control means comprising a first file device and a second file device coupled with each other wherein said first file device operates as a main file device to control communication of said data with said master terminal and said plurality of satellite terminals and said second file device is a backup file device which operates as a main file device upon slowing down or failure of said main file device when sequentially polling said master terminal and said plurality of satellite terminals for said predetermined interval of time and said second file device operates to maintain updating of said point of said data file wherein said file control section controls communication of said data with the terminal from which a request is made.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×