583
32099I–01/2012
AT32UC3L016/32/64
25. Peripheral Event System
Rev: 1.0.0.1
25.1
Features
Direct peripheral to peripheral communication system
Allows peripherals to receive, react to, and send peripheral events without CPU intervention
Cycle deterministic event communication
Asynchronous interrupts allow advanced peripheral operation in low power sleep modes
25.2
Overview
Several peripheral modules can be configured to emit or respond to signals known as peripheral
events. The exact condition to trigger a peripheral event, or the action taken upon receiving a
peripheral event, is specific to each module. Peripherals that respond to peripheral events are
called peripheral event users and peripherals that emit peripheral events are called peripheral
event generators. A single module can be both a peripheral event generator and user.
The peripheral event generators and users are interconnected by a network known as the
Peripheral Event System. This allows low latency peripheral-to-peripheral signaling without CPU
intervention, and without consuming system resources such as bus or RAM bandwidth. This
offloads the CPU and system resources compared to a traditional interrupt-based software
driven system.
25.3
Peripheral Event System Block Diagram
Figure 25-1. Peripheral Event System Block Diagram
25.4
Functional Description
25.4.1
Configuration
The Peripheral Event System in the AT32UC3L016/32/64 has a fixed mapping of peripheral
does not need to configure the interconnection between the modules, although each peripheral
event can be enabled or disabled at the generator or user side as described in the peripheral
chapter for each module.
Peripheral
Event
System
Generator
User
Generator/
User