Datasheet

Section 13 Serial Communication Interface
Page 448 of 846 REJ09B0140-0900 Rev. 9.00
Sep 16, 2010
H8S/2215 Group
13.7.2 Data Format (Except for Block Transfer Mode)
Figure 13.26 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
one 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.
Ds D0 D1 D2 D3 D4 D5 D6 D7 Dp
When there is no parity error
Transmitting station output
Ds D0 D1 D2 D3 D4 D5 D6 D7 Dp
When a parity error occurs
Transmitting station output
DE
Receiving station
output
Start bit
Data bits
Parity bit
Error signal
Legend:
D
S
:
D0 to D7:
Dp:
DE:
Figure 13.26 Normal Smart Card Interface Data Format
Data transfer with other types of IC cards (direct convention and inverse convention) are
performed as described in the following.
Ds
AZZAZZ ZZAA(Z) (Z) State
D0 D1 D2 D3 D4 D5 D6 D7 Dp
Figure 13.27 Direct Convention (SDIR = SINV = O/E = 0)
With the direction convention type IC and the above sample start character, the logic 1 level
corresponds to state Z and the logic 0 level to state A, and transfer is performed in LSB-first order.
The start character data above is H'3B. For the direct convention type, clear the SDIR and SINV