Abstract: A method and apparatus for real-time data stamping via datalink and volatile ECM timer/clock. An engine control module (ECM) includes a volatile time-keeping mechanism, such as time-keeping software code inserted into the ECM software, which is capable of keeping track of elapsed time as long as the ECM microprocessor is powered. The ECM initially sets the volatile time-keeping mechanism with real time (RT) at ECM power up by retrieving the current RT over an attached datalink from a non-volatile RT clock (i.e. a clock that keeps track of time even during ECM power down). Thereafter, the ECM microprocessor may time stamp stored data using RT from the volatile time-keeping mechanism. The present invention thus precludes the need to provide a dedicated RT clock for the ECM, or the need for the ECM to request RT over the datalink every time the ECM wishes to time stamp data to be stored.

Abstract: A system and method for engine parameter trending in which the engine control module (ECM) periodically stores to non-volatile memory various engine operating parameters over the life of the engine. The system is configurable such that a variable number of samples of a variable number of engine parameters can be stored. In addition to storing each engine parameter, each write to non-volatile memory is also time stamped. This data is used to track the health of the engine over its life cycle. Such data can be useful in providing decreased down time due to increased troubleshooting ability. The system includes a variable number of calibratable predetermined trigger points available so that the data is always logged under the same operating conditions. All triggers must be satisfied for a specified time in order to ensure consistent engine operating conditions when each data set is taken.