Datasheet

Section 14 Serial Communication Interface (SCI, IrDA)
Rev.6.00 Mar. 18, 2009 Page 606 of 980
REJ09B0050-0600
As in the above sample start character, with the direct convention type, 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
bits in SCMR to 0. According to the Smart Card regulations, clear the O/E bit in SMR to 0 to
select even parity mode.
Ds
AZZAAA ZAAA(Z) (Z) State
D7 D6 D5 D4 D3 D2 D1 D0 Dp
Figure 14.24 Inverse Convention (SDIR = SINV = O/E = 1)
With the inverse convention type, the logic 1 level corresponds to state A and the logic 0 level to
state Z, and transfer is performed in MSB-first order. The start character data above is H'3F. For
the inverse convention type, set the SDIR and SINV bits in SCMR to 1. According to the Smart
Card regulations, even parity mode is the logic 0 level of the parity bit, and corresponds to state Z.
In this LSI, the SINV bit inverts only data bits D7 to D0. Therefore, set the O/E bit in SMR to 1
to invert the parity bit for both transmission and reception.
14.7.3 Block Transfer Mode
Operation in block transfer mode is the same as that in normal Smart Card interface, except for the
following points.
• In reception, though the parity check is performed, no error signal is output even if an error is
detected. However, the PER bit in SSR is set to 1 and must be cleared before receiving the
parity bit of the next frame.
• In transmission, a guard time of at least 1 etu is left between the end of the parity bit and the
start of the next frame.
• In transmission, because retransmission is not performed, the TEND flag is set to 1, 11.5 etu
after transmission start.
• As with the normal Smart Card interface, the ERS flag indicates the error signal status, but
since error signal transfer is not performed, this flag is always cleared to 0.
Note: etu: Elementary Time Unit (time for transfer of 1 bit)
14.7.4 Receive Data Sampling Timing and Reception Margin
Only the internal clock generated by the on-chip baud rate generator is used as transmit/receive
clock in Smart Card interface. In Smart Card interface mode, the SCI operates on a basic clock
with a frequency of 32, 64, 372, or 256 times the bit rate (fixed at 16 times in normal