Datasheet

Section 15 Serial Communication Interface (SCI, IrDA)
Page 922 of 1408 R01UH0309EJ0500 Rev. 5.00
Sep 24, 2012
H8S/2456, H8S/2456R, H8S/2454 Group
15.7.2 Data Format (Except for Block Transfer Mode)
Figure 15.22 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: 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 the elapse 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]
Ds:
D0 to D7:
Dp:
DE:
Figure 15.22 Normal Smart Card Interface Data Format
Data transfer with the 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 15.23 Direct Convention (SDIR = SINV = O/E = 0)