SH7751 Datasheet, PDF (758/1224 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

15. Serial Communication Interface (SCI)
Transfer
direction
Serial clock
Serial data
LSB
Bit 0
Bit 1
MSB
Bit 7
Bit 0
Bit 1
Bit 6 Bit 7
TDRE
TEND
TXI interrupt
request
Data written to SCTDR1
and TDRE flag cleared to
0 in TXI interrupt handler
One frame
TXI interrupt
request
TEI interrupt
request
Figure 15.21 Example of SCI Transmit Operation
Serial Data Reception (Synchronous Mode): Figure 15.22 shows a sample flowchart for serial
reception.
Use the following procedure for serial data reception after enabling the SCI for reception.
When changing the operating mode from asynchronous to synchronous, be sure to check that the
ORER, PER, and FER flags are all cleared to 0. The RDRF flag will not be set if the FER or PER
flag is set to 1, and neither transmit nor receive operations will be possible.
Rev.4.00 Oct. 10, 2008 Page 660 of 1122
REJ09B0370-0400