×

Multiple application chip card with decoupled programs

  • US 5,912,453 A
  • Filed: 09/25/1996
  • Issued: 06/15/1999
  • Est. Priority Date: 09/29/1995
  • Status: Expired due to Fees
First Claim
Patent Images

1. A data-carrier card comprising a memory for recording a plurality of applications and a processor, the card further comprising:

  • means for separating at least two of said applications in the memory, so that each application may only gain access to a specified predetermined memory area within the memory, and that access of applications outside of the specified predetermined memory area in the memory for the respective application is disabled;

    said means for separating further comprising;

    an application table, which has stored the information concerning an initial address A and an end address E of the memory area in which a respective application may have access; and

    address-monitoring means which monitors the addresses filed on an address bus to ensure that the filed addresses locate a memory area A to E of the application in the memory which is defined by the initial address A and the end address E of the respective application, and which initiates an appropriate action when one of the addresses filed on the address bus is not located within the memory area A to E of the application in the memory;

    said address-monitoring means further comprising;

    address decoder means which decodes and authorizes the memory area, whereby addresses outside of the memory area are ignored.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×