Renesas ZTAT H8S/2357F, Hardware Manual

Page: 560 / 1047

Rev.6.00 Oct.28.2004 page 532 of 1016
REJ09B0138-0600H
Serial Data Reception: Data reception in Smart Card mode uses the same processing procedure as for the normal SCI.
Figure 15-7 shows an example of the transmission processing flow.
[1] Perform Smart Card interface mode initialization as described above in Initialization.
[2] Check that the ORER flag and PER flag in SSR are cleared to 0. If either is set, perform the appropriate receive error
processing, then clear both the ORER and the PER flag to 0.
[3] Repeat steps [2] and [3] until it can be confirmed that the RDRF flag is set to 1.
[4] Read the receive data from RDR.
[5] When receiving data continuously, clear the RDRF flag to 0 and go back to step [2].
[6] To end reception, clear the RE bit to 0.
Initialization
Read RDR and clear
RDRF flag in SSR to 0
Clear RE bit to 0
Start reception
Start
Error processing
No
No
No
Yes
Yes
ORER = 0 and
PER = 0
RDRF=1?
All data received?
Yes
Figure 15-7 Example of Reception Processing Flow
With the above processing, interrupt servicing or data transfer by the DMAC or DTC is possible.
If reception ends and the RDRF flag is set to 1 while the RIE bit is set to 1 and interrupt requests are enabled, a receive
data full interrupt (RXI) request will be generated. If an error occurs in reception and either the ORER flag or the PER flag
is set to 1, a transfer error interrupt (ERI) request will be generated.
If the DMAC or DTC is activated by an RXI request, the receive data in which the error occurred is skipped, and only the
number of bytes of receive data set in the DMAC or DTC are transferred.
For details, see Interrupt Operation and Data Transfer Operation by DMAC or DTC below.