HD64F3028F25 Datasheet, PDF (536/925 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

Figure 13.19 shows an example of SCI receive operation.
Serial clock
Serial data
Bit 7 Bit 0
Bit 7 Bit 0 Bit 1
Bit 6 Bit 7
RDRF
ORER
RXI interrupt
request
RXI interrupt handler
reads data in RDR and
clears RDRF flag to 0
RXI interrupt
request
Overrun error,
ERI interrupt
request
1 frame
Figure 13.19 Example of SCI Receive Operation
Rev. 2.00, 09/03, page 504 of 890