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:
Sep. 16, 1997
Filed:
Dec. 16, 1994
Hiroshi Kondo, Anjo, JP;
Takamasa Oguri, Toyoake, JP;
Masato Yano, Okazaki, JP;
Kazuyuki Okuda, Kariya, JP;
Yoshihiro Kitagawa, Nagoya, JP;
Nippondenso Co, Ltd., Aichi-pref., JP;
Abstract
A backup RAM for storing pieces of diagnosis data regardless of the cut-off of an electric power is provided in a portion of a RAM. In cases where the detection of an unusual condition by a throttle sensor or a water temperature sensor is judged by a CPU in a current processing routine, a first checking value indicating that the backup RAM is in a renewing period is stored in a checking region of the backup RAM, and pieces of previous diagnosis data stored in a data access region of the backup RAM in a previous processing routine are copied to a temporary refuge region of the backup RAM. Thereafter, pieces of updated diagnosis data obtained in the current processing routine are stored one by one in the data access region in place of the previous diagnosis data, and a second checking value indicating that the backup RAM is in a renewal finishing period is stored in the checking region. In cases where the first checking data is stored in the checking region when the electric power cut off is again supplied, the previous diagnosis data stored in the temporary refuge region are returned to the data access region and are read out according to a request from a diagnosis checker.