H8S2258 Datasheet, PDF (696/1071 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcomputer H8S Family/H8S/2200 Series

Section 15 Serial Communication Interface (SCI)
15.7 Operation in Smart Card Interface
The SCI supports an IC card (Smart Card) interface that conforms to ISO/IEC 7816-3
(Identification Card) as a serial communication interface extension function. Switching between
the normal serial communication interface and the Smart Card interface mode is carried out by
means of a register setting.
15.7.1 Pin Connection Example
Figure 15.24 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, the TxD
pin and RxD pin should be connected to the LSI pin. The data transmission line should be pulled
up to the V_CC power supply with a resistor. If an IC card is not connected, and the TE and RE bits
are both set to 1, closed transmission/reception is possible, enabling self-diagnosis to be carried
out. When the clock generated on the Smart Card interface is used by an IC card, the SCK pin
output is input to the CLK pin of the IC card. This LSI port output is used as the reset signal.
TxD
RxD
SCK
Px (port)
This LSI
Connected equipment
V_CC
Data line
Clock line
Reset line
I/O
CLK
RST
IC card
Figure 15.24 Schematic Diagram of Smart Card Interface Pin Connections
15.7.2 Data Format (Except for Block Transfer Mode)
Figure 15.25 shows the transfer data format in Smart Card interface mode.
• One frame consists of 8-bit data plus a parity bit in asynchronous mode.
• In transmission, a guard time of at least 2 etu (Elementary Time Unit: the time for transfer of 1
bit) is left between the end of the parity bit and the start of the next frame.
• If a parity error is detected during reception, a low error signal level is output for one etu
period, 10.5 etu after the start bit.
• If an error signal is sampled during transmission, the same data is retransmitted automatically
after a delay of 2 etu or longer.
Rev. 5.00 Aug 08, 2006 page 610 of 982
REJ09B0054-0500