Toshiba TLCS-900/H1 Series Manual page 188

3.9.5 Support for IrDA
SIO0 includes support for the IrDA 1.0 infrared data communication specification.
Figure 3.9.24 shows the block diagram.
Transmission data
SIO0
Receive
(1) Modulation of the transmission data
When the transmit data is 0, the modem outputs 1 to TXD0 pin with either 3/16 or
1/16 times for width of baud rate. The pulse width is selected by the SIRCR<PLSEL>.
When the transmit data is 1, the modem outputs 0.
Transmission
data
TXD0 pin
(2) Modulation of the receive data
When the receive data has an effective pulse width of "1", the modem outputs "0" to
SIO0. Otherwise the modem outputs "1" to SIO0. The effective pulse width is selected
by SIRCR<SIRWD3:0>.
RXD0 pin
Receive data
IR modulator
Modem
IR demodulator
data
TMP92CH21
Figure 3.9.24 Block Diagram
Start
0 1
Figure 3.9.25 Transmission Example
Start
1 0
Figure 3.9.26 Receiving Example
92CH21-186
TXD0
IR transmitter & LED
RXD0
IR receiver
0 0 1
0 1 0
TMP92CH21
IR output
IR input
1 0 0
Stop
1 1 0
Stop
2009-06-19