Datasheet

683
32142D–06/2013
ATUC64/128/256L3/4U
27. Peripheral Event System
Rev: 1.0.0.1
27.1 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
27.2 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.
27.3 Peripheral Event System Block Diagram
Figure 27-1. Peripheral Event System Block Diagram
27.4 Functional Description
27.4.1 Configuration
The Peripheral Event System in the ATUC64/128/256L3/4U has a fixed mapping of peripheral
events between generators and users, as described in Table 27-1 to Table 27-4. Thus, the user
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
Generator
User
Generator/
User