Samsung S3C2440A - Manual (Page 312)

UART S3C2440A RISC MICROPROCESSOR
11-8
Infrared (IR) Mode
The S3C2440A UART block supports infrared (IR) transmission and reception, which can be selected by setting
the Infrared-mode bit in the UART line control register (ULCONn). Figure 11-4 illustrates how to implement the IR
mode.
In IR transmit mode, the transmit pulse comes out at a rate of 3/16, the normal serial transmit rate (when the
transmit data bit is zero); In IR receive mode, the receiver must detect the 3/16 pulsed period to recognize a zero
value (see the frame timing diagrams shown in Figure 11-6 and 11-7).
IrDA Tx
Encoder
0
1
0
1
IrDA Rx
Decoder
TxD
RxD
TxD
IRS
RxD
RE
UART
Block
Figure 11-3. IrDA Function Block Diagram