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:
May. 14, 1991
Filed:
Dec. 01, 1988
Atsuo Yamaguchi, Itami, JP;
Shigeru Furuta, Itami, JP;
Takesi Inoue, Itami, JP;
Kenichi Takahira, Itami, JP;
Shuzo Fujioka, Itami, JP;
Toshiyuki Matsubara, Itami, JP;
Abstract
An IC card has a CPU, a first memory for storing a test program, a second memory for storing an application progam, a bus connecting the CPU and the first and second memories. A detection circuit for detecting whether the CPU has began executing the application program stored in the second memory, and a disconnection circuit for disconnecting the first memory from the bus when the detection circuit detects that the CPU has begun executing the application program. The above-described arrangement makes it impossible to access the test program in the system ROM from the application program thereby preventing the occurrence of incorrect access.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile