ATXMEGA16E5_14 Datasheet, PDF (18/147 Pages) ATMEL Corporation – 8/16-bit Atmel AVR XMEGA Microcontrollers

10. Event System
10.1
Features
z System for direct peripheral-to-peripheral communication and signaling
z Peripherals can directly send, receive, and react to peripheral events
z CPU and EDMA controller independent operation
z 100% predictable signal timing
z Short and guaranteed response time
z Synchronous and asynchronous event routing
z Eight event channels for up to eight different and parallel signal routing and configurations
z Events can be sent and/or used by most peripherals, clock system, and software
z Additional functions include
z Quadrature decoder with rotary filtering
z Digital filtering of I/O pin state with configurable filter
z Simultaneous synchronous and asynchronous events provided to peripheral
z Works in all sleep modes
10.2
Overview
The event system enables direct peripheral-to-peripheral communication and signaling. It allows a change in one
peripheral’s state to automatically trigger actions in other peripherals. It is designed to provide a predictable system for
short and predictable response times between peripherals. It allows for autonomous peripheral control and interaction
without the use of interrupts, CPU, or EDMA controller resources, and is thus a powerful tool for reducing the complexity,
size and execution time of application code. It allows for synchronized timing of actions in several peripheral modules.
The event system enables also asynchronous event routing for instant actions in peripherals.
A change in a peripheral’s state is referred to as an event, and usually corresponds to the peripheral’s interrupt
conditions. Events can be directly passed to other peripherals using a dedicated routing network called the event routing
network. How events are routed and used by the peripherals is configured in software.
Figure 10-1 shows a basic diagram of all connected peripherals. The event system can directly connect together analog
and digital converters, analog comparators, I/O port pins, the real-time counter, timer/counters, IR communication
module (IRCOM) and XMEGA Custom Logic (programmable logic) block (XCL). It can also be used to trigger EDMA
transactions (EDMA controller). Events can also be generated from software and peripheral clock.
XMEGA E5 [DATASHEET] 18
Atmel-8153I–AVR-ATxmega8E5-ATxmega16E5-ATxmega32E5_Datasheet–08/2014