HD6473837H Datasheet, PDF (306/562 Pages) Renesas Technology Corp – Hardware Manual

Receiving Multiprocessor Data: Figure 10.25 shows a typical flow chart for receiving data using
a multiprocessor format. After SCI3 initialization, follow the procedure below.
Start
1 Set bit MPIE in SCR3 to 1
2 Read bits OER and FER in SSR
Yes
OER + FER = 1?
No
3
Read bit RDRF in SSR
No
RDRF = 1?
Yes
Read received data in RDR
No
Own ID?
Yes
Read bits OER and FER in SSR
Yes
OER + FER = 1?
No
4
Read bit RDRF in SSR
No
RDRF = 1?
Yes
Read received data in RDR
5 Error processing
1. Set bit MPIE in serial control register 3 (SCR3) to 1.
2. Read bits OER and FER in the serial status register (SSR)
to determine if an error has occurred. If a receive error has
occurred, receive error processing is executed.
3. Read the serial status register (SSR) and confirm that
RDRF = 1. If RDRF = 1, read the data in the received data
register (RDR) and compare it with the processor’s own ID.
If the received data does not match the ID, set bit MPIE to
1 again. Bit RDRF is automatically cleared to 0 when data
in the received data register (RDR) is read.
4. Read SSR, check that bit RDRF = 1, then read received
data from the receive data register (RDR).
5. If a receive error occurs, read bits OER and FER in SSR
to determine which error occurred. After the necessary
error processing, be sure to clear the error flags to 0.
Serial data transfer cannot take place while
bit OER or FER is set to 1.
When a framing error occurs, a break can be detected by
reading the RXD pin value.
Yes
Continue receiving?
No
Clear bit RE in SCR3 to 0
End
A Start receive error processing
Yes
OER = 1?
No
Yes
FER = 1?
No
Clear bits OER and
FER in SSR to 0.
End receive error processing
Overrun error
processing
Yes
Break?
No
Framing error
processing
A
Figure 10.25 Typical Flow Chart for Receiving Serial Data Using Multiprocessor Format
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