HD64F2168 Datasheet, PDF (448/874 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer

In normal transmission/reception
Ds D0 D1 D2 D3 D4 D5 D6 D7 Dp
Output from the transmitting station
When a parity error is generated
Ds D0 D1 D2 D3 D4 D5 D6 D7 Dp
DE
[Legend]
Ds:
Start bit
D0 to D7: Data bits
Dp:
Parity bit
DE:
Error signal
Output from the transmitting station
Output from
the receiving station
Figure 14.25 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.
(Z)
A ZZ A ZZ ZAA Z
(Z) state
Ds D0 D1 D2 D3 D4 D5 D6 D7 Dp
Figure 14.26 Direct Convention (SDIR = SINV = O/E = 0)
For the direct convention type, logic levels 1 and 0 correspond to states Z and A, respectively, and
data is transferred with LSB-first as the start character, as shown in figure 14.26. Therefore, data
in the start character in the figure is H'3B. When using the direct convention type, write 0 to both
the SDIR and SINV bits in SCMR. Write 0 to the O/E bit in SMR in order to use even parity,
which is prescribed by the smart card standard.
(Z)
A ZZ A AA AAA Z
(Z) state
Ds D7 D6 D5 D4 D3 D2 D1 D0 Dp
Figure 14.27 Inverse Convention (SDIR = SINV = O/E = 1)
For the inverse convention type, logic levels 1 and 0 correspond to states A and Z, respectively
and data is transferred with MSB-first as the start character, as shown in figure 14.27. Therefore,
data in the start character in the figure is H'3F. When using the inverse convention type, write 1 to
both the SDIR and SINV bits in SCMR. The parity bit is logic level 0 to produce even parity,
Rev. 3.00, 03/04, page 408 of 830