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Receiving
Figure 10-8 shows an example of a flowchart for data reception. This procedure should be followed
for data reception after initializing SCI3.
Figure 10-8 Example of Data Reception Flowchart (Asynchronous Mode)
Start
End
Read bits OER,
PER, FER in SSR
1
2
3
4
Read bit RDRF
in SSR
Read receive
data in RDR
Clear bit RE to
0 in SCR3
Yes
OER + PER
+ FER = 1?
No
RDRF = 1?
Yes
Continue data
reception?
No
No
Yes
Receive error
processing
(A)
Read bits OER, PER, and FER in the
serial status register (SSR) to determine
if there is an error. If a receive error has
occurred, execute receive error
processing.
Read SSR and check that bit RDRF is
set to 1. If it is, read the receive data
in RDR. When the RDR data is read,
bit RDRF is cleared to 0 automatically.
When continuing data reception, finish
reading of bit RDRF and RDR before
receiving the stop bit of the current
frame. When the data in RDR is read,
bit RDRF is cleared to 0 automatically.
1.
2.
3.