14.2 Overview

The Event System (EVSYS) enables direct peripheral-to-peripheral signaling. It allows a change in one peripheral (the event generator) to trigger actions in other peripherals (the event users) through event channels, without using the CPU. It is designed to provide short and predictable response times between peripherals, allowing for autonomous peripheral control and interaction, and also for the synchronized timing of actions in several peripheral modules. It is thus a powerful tool for reducing the complexity, size, and the execution time of the software.

A change of the event generator's state is referred to as an event and usually corresponds to one of the peripheral's interrupt conditions. Events can be directly forwarded to other peripherals using the dedicated event routing network. The routing of each channel is configured in software, including event generation and use.

Only one trigger from an event generator peripheral can be routed on each channel, but multiple channels can use the same generator source. Multiple peripherals can use events from the same channel.

A channel path can be either asynchronous or synchronous to the main clock. The mode must be selected based on the requirements of the application.

The Event System can directly connect analog and digital converters, analog comparators, I/O port pins, the real-time counter, timer/counters, and the configurable custom logic peripheral. Events can also be generated from software and the peripheral clock.