SH7144_08 Datasheet, PDF (495/930 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperHTM RISC engine Family/SH7144 Series

13. Serial Communication Interface (SCI)
13.7 Smart Card Interface
The SCI supports an IC card (smart card) interface that conforms to ISO/IEC 7816-3
(Identification Card) as an extension function for the serial communication interface. Switching to
smart card interface mode is carried out by means of a register setting.
13.7.1 Pin Connection Example
Figure 13.21 shows an example of connection with the smart card. In communication with an IC
card, as both transmission and reception are carried out on a single data transmission line, but the
TxD pin is always fixed to output. Note that the following controls are needed to avoid signal
collision: (1) control of data directions between TXD and I/O in the external circuit and (2) setting
of the TXD pin to an input port except in transmission. Similarly, since the RxD pin is always
fixed to input, connect a pull-up resistor to avoid the open state.
When the clock generated by the SCI is supplied to an IC card, the SCK pin output is input to the
CLK pin of the IC card. If an internal clock is used in an IC card, the connection between the SCK
and CLK pins is unnecessary. This LSI port output can be used as the reset signal. Connection
between the power supply and ground pins is also necessary.
TxD
RxD
SCK
Port
This LSI
External circuit
VCC
Data line
Clock line
Reset line
I/O
CLK
RST
IC card
Figure 13.21 Example of Pin Connections for Smart Card Interface
Rev.4.00 Mar. 27, 2008 Page 451 of 882
REJ09B0108-0400