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:
Oct. 31, 1989
Filed:
Nov. 09, 1987
Kunio Fujisaki, Aichi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An IC card system comprises an IC card, each card including a microprocessor, a communication interface, a power supply interface, and memories such as RAM, ROM and EEPROM, and an external device such as a terminal. The terminal functions to supply electric power and send commands to the IC card, and includes a card reader/writer effecting data processing for transactions. The commands include a start command and an end command for the transaction data processing for the IC card connected therewith, and the IC card comprises a validity data flag table within the EEPROM. When a start command is received, the flag table records the validity flag in an invalid state and holds such state as long as an end command is not received.