SH7020 Datasheet, PDF (406/509 Pages) Renesas Technology Corp – SuperH™ RISC engine

Error handling
No
ORER = 1?
Yes
Overrun error handling
Clear ORER bit of SSR to 0
End
Figure 13.18 Sample Flowchart for Serial Receiving (cont)
Receive direction
Serial
clock
Serial
data
Bit 7 Bit 0
Bit 7 Bit 0 Bit 1
Bit 6 Bit 7
RDRF
ORER
RXI interrupt handler
RXI request ^{reads data in RDR}
and clears RDRF to 0
RXI request
1 frame
Overrun
error, ERI
request
Figure 13.19 Example of SCI Receive Operation
In receiving, the SCI operates as follows:
1. The SCI synchronizes with serial clock input or output and initializes internally.
2. Receive data is shifted into the RSR in order from the LSB to the MSB. After receiving the
data, the SCI checks that RDRF is 0 so that receive data can be loaded from the RSR into the
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