Renesas H8S/2100 Series, Hardware Manual

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Section 15 Serial Communication Interface (SCI)
Rev. 1.00 Apr. 28, 2008 Page 450 of 994
REJ09B0452-0100
15.7.2 Data Format (Except in Block Transfer Mode)
Figure 15.22 shows the data transfer formats in smart card interface mode.
•
One frame contains 8-bit data and a parity bit in asynchronous mode.
•
During transmission, at least 2 etu (elementary time unit: time required for transferring one bit)
is secured as a guard time after the end of the parity bit before the start of the next frame.
•
If a parity error is detected during reception, a low error signal is output for 1 etu after 10.5 etu
has passed from the start bit.
•
If an error signal is sampled during transmission, the same data is automatically re-transmitted
after two or more etu.
Ds D0 D1 D2 D3 D4 D5 D6 D7 Dp
In normal transmission/reception
Output from the transmitting station
Ds D0 D1 D2 D3 D4 D5 D6 D7 Dp
When a parity error is generated
Output from the transmitting station
DE
Output from
the receiving station
[Legend]
Ds:
Start bit
D0 to D7 : Data bits
Dp:
Parity bit
DE: Error signal
Figure 15.22 Data Formats in Normal Smart Card Interface Mode
For communication with the IC cards of the direct convention and inverse convention types,
follow the procedure below.
Ds
A Z Z A Z Z Z Z A A (Z) (Z) state
D0 D1 D2 D3 D4 D5 D6 D7 Dp
Figure 15.23 Direct Convention (SDIR = SINV = O/
E
= 0)