System and method of reducing chronometric load

A system for improving the control quality of a vehicle engine having a rotatable and positionable crankshaft by prioritizing tasks to be performed by a microprocessor preprogrammed with an inventory of foreground and background engine tasks affecting the efficiency and performance of the vehicle, the system comprising:

• a first mechanism for selectively sensing the speed of rotation of the crankshaft to provide a first, second, or third signal indicative of respective low, medium, or high crankshaft speeds;
• a second mechanism for sensing the position of the crankshaft to provide a fourth signal of the crankshaft position;
• and
• a third mechanism for processing these signals to select:
• (a) foreground tasks for execution, if the fourth signal is received to indicate the crankshaft is at a predetermined position;
• (b) a first set of such foreground tasks for execution in a first manner, if the first signal is received to indicate a low crankshaft speed;
• (c) a second set of such foreground tasks for execution in a second manner, if the second signal is received to indicate a medium crankshaft speed;
• and
• (d) a third set of such foreground tasks for execution in a third manner, if the third signal is received to indicate a high crankshaft speed, whereby background engine tasks may be executed by the microprocessor based on the priority for execution such microprocessor accords the selection of first, second or third sets of the foreground tasks.

A method of prioritizing the operation of a microprocessor in the control of a vehicle's powertrain having parts movable at variable speed and position comprising:

• preprogramming the microprocessor for executing a plurality of high priority control tasks and low priority control tasks;
• sensing the speed of at least one of the powertrain parts when a powertrain part is at a predetermined position;
• and
• selecting less of the high priority tasks for execution by the microprocessor in the control of the vehicle's powertrain, when the speed sensed is low than when the speed is sensed high, whereby to provide for execution of more of the lower priority control tasks when the speed is sensed low.