HD6473032F16 Datasheet, PDF (549/847 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

Section 14 Smart Card Interface
• Retransmission when SCI is in Transmit Mode (See Figure 14.12)
6. After transmitting one frame, if the receiving device returns an error signal, the SCI sets the
ERS flag to 1 in SSR. If the RIE bit in SCR is set to the enable state, an ERI interrupt is
requested. The ERS flag should be cleared to 0 in SSR before the next parity bit sampling
timing.
7. The TEND bit in SSR is not set for the frame in which the error signal was received,
indicating an error.
8. If no error signal is returned from the receiving device, the ERS flag is not set in SSR.
9. If no error signal is returned from the receiving device, transmission of the frame, including
retransmission, is assumed to be complete, and the TEND bit is set to 1 in SSR. If the TIE
bit in SCR is set to the enable state, a TXI interrupt is requested. If TXI is enabled as a
DMA transfer activation source, the next data can be written in TDR automatically. When
the DMAC writes data in TDR, it automatically clears the TDRE bit to 0.
Frame n
Retransmitted frame
Ds D0 D1 D2 D3 D4 D5 D6 D7 Dp DE
(DE)
Ds D0 D1 D2 D3 D4 D5 D6 D7 Dp
Frame n + 1
Ds D0 D1 D2 D3 D4
TDRE
Transfer from TDR to TSR
TEND
ERS
Transfer from TDR to TSR
(7)
(6)
Transfer from
TDR to TSR
(9)
(8)
Figure 14.12 Retransmission in SCI Transmit Mode
Rev. 3.00 Mar 21, 2006 page 519 of 814
REJ09B0302-0300