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:
Jan. 21, 1986
Filed:
Sep. 21, 1984
Takeshi Hirayama, Mito, JP;
Matsuo Amano, Hitachi, JP;
Shinichi Sakamoto, Hitachi, JP;
Masami Shiida, Mito, JP;
Shirou Baba, Tokorozawa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An engine control apparatus includes a microprocessor, a ROM for holding a program required for the operation of the microprocessor, and a RAM for holding data supplied from the microprocessor. Pulse signals representative of results of the arithmetic operations executed by the arithmetic unit on the basis of input signals available from various sensors as well as data stored in the memory in accordance with the program are supplied to actuators for controlling engine operations through an input/output circuit. The control apparatus further includes a counter for counting crank angle pulses produced in synchronism with rotation of the engine shaft, an interrupt request generating circuit for requiring an interrupt to the microprocessor when overflow occurs in the counter. In response to every interrupt request, the microprocessor causes the count value held in the RAM to be incremented by unity. After elapse of a period for measuring the rotational speed of the engine, the count value held in the counter of the input/output circuit is corrected by the number of overflows held in the RAM.