316
8331B–AVR–03/12
Atmel AVR XMEGA AU
24. IRCOM - IR Communication Module
24.1
Features
•
Pulse modulation/demodulation for infrared communication
•
IrDA compatible for baud rates up to 115.2kbps
•
Selectable pulse modulation scheme
– 3/16 of the baud rate period
– Fixed pulse period, 8-bit programmable
– Pulse modulation disabled
•
Built-in filtering
•
Can be connected to and used by any USART
24.2
Overview
XMEGA devices contain an infrared communication module (IRCOM) that is IrDA compatible for
baud rates up to 115.2kbps. It can be connected to any USART to enable infrared pulse encod-
ing/decoding for that USART.
Figure 24-1.
IRCOM connection to USARTs and associated port pins.
The IRCOM is automatically enabled when a USART is set in IRCOM mode. The signals
between the USART and the RX/TX pins are then routed through the module as shown in
. The data on the TX/RX pins are the inverted value of the transmitted/received
infrared pulse. It is also possible to select an event channel from the event system as input for
the IRCOM receiver. This will disable the RX input from the USART pin.
IRCOM
Pulse
Decoding
DIF
Event System
RXDxn
TXDxn
USARTxn
....
USARTD0
USARTC0
RXDD0
TXDD0
RXDC0
TXDC0
Pulse
Encoding
decoded RXD
encoded TXD
encoded RXD
RXD...
TXD...
decoded TXD
events