An AI Engine event gives information about the system at a specific instant in time. An event that is associated with a timestamp, type and set of data values is referred to as a payload. The interpretation of the payload depends on the type of the event. A timestamp allows ordering of events, computation of causality relationships, and implementation of verifiers on a sequence of events.
For event modeling purposes, the key modules of the AI Engine array are processor, DMA, lock modules, memory, and I/O streams. Each module can be viewed as an event generator/responder. Each module receives an event and responds to the event. As a response, new events could be generated. Events are classified based on the generator of the events. The timestamp is not mentioned explicitly in the event definitions. Each event is described with a payload, which is a couple of values associated with the event. Each AI Engine, memory, DMA, or lock is addressable by a two-dimensional index <col, row>, which is the column and row index in the AI Engine array.