4. Production and development

4.1 Notions of real time constraints

The processor is required to perform a very large number of operations, which must be renewed frequently enough to keep pace with the evolution of engine requirements over time. A large number of operations have to be refreshed each time one of the four cycle times of one of the cylinders begins, to be able to associate with each combustion the parameters that determine its optimal energy and quality.

The processor's computing power and speed must, of course, match this requirement. In practice, for reasons of economy, the microprocessor has to be sized as precisely as possible, and the number of calculations carried out reduced as much as possible, which means refreshing calculations at the minimum frequency compatible...