h8s-2138 Renesas Electronics Corporation., h8s-2138 Datasheet - Page 501

• Manufacturer Part Number: h8s-2138
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

15.3.5
Figure 15.21 shows a block diagram of the IrDA function.
When the IrDA function is enabled with bit IrE in KBCOMP, the SCI channel 2 TxD2 and RxD2
signals are subjected to waveform encoding/decoding conforming to IrDA specification version
1.0 (IrTxD and IrRxD pins). By connecting these pins to an infrared transceiver/receiver, it is
possible to implement infrared transmission/reception conforming to the IrDA specification
version 1.0 system.
In the IrDA specification version 1.0 system, communication is started at a transfer rate of 9600
bps, and subsequently the transfer rate can be varied as necessary. As the IrDA interface in the
H8S/2138 Group and H8S/2134 Group does not include a function for varying the transfer rate
automatically, the transfer rate setting must be changed by software.
Transmission: In transmission, the output signal (UART frame) from the SCI is converted to an
IR frame by the IrDA interface (see figure 15.22).
When the serial data is 0, a high-level pulses of 3/16 the bit rate (interval equivalent to the width
of one bit) is output (initial value). The high-level pulse can be varied according to the setting of
bits IrCKS2 to IrCKS0 in KBCOMP.
IrDA Operation
TxD2/IrTxD
RxD2/IrRxD
Figure 15.21 Block Diagram of IrDA Function
Pulse encoder
Pulse decoder
KBCOMP
Section 15 Serial Communication Interface (SCI, IrDA)
IrDA
Rev. 4.00 Jun 06, 2006 page 447 of 1004
RxD
TxD
SCI2
REJ09B0301-0400