AT32AP7000_1 Datasheet, PDF (420/973 Pages) ATMEL Corporation – AVR32 32-bit Microcontroller

AT32AP7000
24.7.4.7
MAX_ITERATION is reached, the character is considered as correct, an acknowledge is sent on
the line and the ITERATION bit in the Channel Status Register is set.
Protocol T = 1
24.7.5
IrDA Mode
When operating in ISO7816 protocol T = 1, the transmission is similar to an asynchronous for-
mat with only one stop bit. The parity is generated when transmitting and checked when
receiving. Parity error detection sets the PARE bit in the Channel Status Register (CSR).
The USART features an IrDA mode supplying half-duplex point-to-point wireless communica-
tion. It embeds the modulator and demodulator which allows a glueless connection to the
infrared transceivers, as shown in Figure 24-33. The modulator and demodulator are compliant
with the IrDA specification version 1.1 and support data transfer speeds ranging from 2.4 Kb/s to
115.2 Kb/s.
The USART IrDA mode is enabled by setting the MODE field in the Mode Register (MR) to the
value 0x8. The IrDA Filter Register (IFR) allows configuring the demodulator filter. The USART
transmitter and receiver operate in a normal asynchronous mode and all parameters are acces-
sible. Note that the modulator and the demodulator are activated.
Figure 24-33. Connection to IrDA Transceivers
USART
Receiver
Demodulator _RXD
Transmitter
Modulator
TXD
IrDA
Transceivers
RX
TX
24.7.5.1
The receiver and the transmitter must be enabled or disabled according to the direction of the
transmission to be managed.
IrDA Modulation
For baud rates up to and including 115.2 Kbits/sec, the RZI modulation scheme is used. “0” is
represented by a light pulse of 3/16th of a bit time. Some examples of signal pulse duration are
shown in Table 24-9.
Table 24-9.
Baud Rate
2.4 Kb/s
9.6 Kb/s
19.2 Kb/s
IrDA Pulse Duration
Pulse Duration (3/16)
78.13 µs
19.53 µs
9.77 µs
32003M–AVR32–09/09
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