Patent ID: 7802030
Filing Date: 2010-09-21
Classification: F02D

Abstract:
1. An interrupt generation circuit comprising: an edge detection unit that receives a periodic external signal from a monitored object and, upon detecting an effective edge of the external signal, generates an edge detection signal; a main timer for implementing a count value for counting a plurality of pulses of a pulse signal and, when the edge detection signal is generated, for clearing the count value; and an interrupt determination circuit that compares the count value of said main timer with a value stored in a compare register, in which a desired value is stored, for determining whether an interrupt of one or more interrupts is to be generated based on a result of the comparison, wherein, when the edge detection signal is generated, said interrupt determination circuit generates the interrupt at a timing when the edge detection signal is generated if the count value of said main timer is smaller than the value stored in said compare register, wherein the pulses of the pulse signal counted by the count value between the detection of the effective edge of the external signal and a detection of a following effective edge of the external signal are of a uniform pulse width such that the count value of the main timer is incremented at a uniform rate; wherein the count value implemented by the main timer is for counting the pulses of the pulse signal and is not for counting pulses of signals other than the pulse signal.