Figure 14-2 Smart Card Interface Connection Diagram
Note: A loop-back test can be performed by setting both RE and TE to 1 without connecting a
smart card.
14.3.3 Data Format
Figure 14-3 shows the data format of the smart card interface. In receive mode, parity is checked
once per frame. If a parity error is detected, an error signal is returned to the transmitting device to
request retransmission. In transmit mode, the error signal is sampled and the same data is
retransmitted if the error signal is low.
Figure 14-3 Smart Card Interface Data Format
H8/3048 Series
Chip
Card-processing device
Smart card
TxD
0
RxD
0
SCK
0
Px (port)
I/O
CLK
RST
Data line
V
CC
Clock line
Reset line
Ds
Parity error
D0
D1
D2
D3
Output from transmitting device
Output from
receiving device
D4
D5
D6
D7
Dp
DE
Ds
No parity error
D0
D1
D2
D3
Output from transmitting device
D4
D5
D6
D7
Dp
Ds:
D0 to D7:
Dp:
DE:
Start bit
Data bits
Parity bit
Error signal
506
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