The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 13, 1990
Filed:
Feb. 08, 1988
Winslow E Jackson, Monroe, CT (US);
Pitney Bowes Inc., Stamford, CT (US);
Abstract
A fault tolerant smart card is provided having primary functional units including a standard ISO interface, a first microcontroller, a clock, and main memory. Secondary functional units including a secondary microcontroller, secondary memory with bit checking capability and an alternate battery power source are also provided. A microcontroller error detector is connected to both microcontrollers. Should a discrepancy between microcontrollers occur known test patterns are run on the second microcontroller to determine which microcontroller is faulty. A private access port provides alternate access to information stored in the fault tolerant smart card. Registers for funds remaining, error condition and access account are also provided.