Data Format (Except In Block Transfer Mode); Figure 12.22 Data Formats In Normal Smart Card Interface Mode; Figure 12.23 Direct Convention (Sdir = Sinv = O/E = 0) - Renesas H8SX/1520 Series Hardware Manual

Section 12 Serial Communication Interface (SCI)
12.7.2

Data Format (Except in Block Transfer Mode)

Figure 12.22 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 at least 2 etu.
In normal transmission/reception
When a parity error is generated
[Legend]
Ds:
D0 to D7: Data bits

Figure 12.22 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.
Rev. 3.00 Mar. 14, 2006 Page 430 of 804
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Ds D0 D1 D2
Output from the transmitting station
Ds D0 D1 D2
Output from the transmitting station
Start bit Dp: Parity bit
DE: Error signal
(Z) A Z Z A
Ds D0 D1 D2

Figure 12.23 Direct Convention (SDIR = SINV = O/E = 0)

D3 D4 D5 D6
D3 D4 D5 D6
Z Z Z A A
D3 D4 D5 D6 D7
D7 Dp
D7 Dp DE
Output from
the receiving station
Z (Z) state
Dp