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Receiving
Figure 10-13 shows an example of a flowchart for data reception. This procedure should be
followed for data reception after initializing SCI3.
Start
Read bits OER,
PER, FER in SSR
1. 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.
1
Yes
OER + PER
+ FER = 1?
2. 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.
No
Read bit RDRF
in SSR
2
3. 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.
No
RDRF = 1?
Yes
Read receive
data in RDR
Receive error
processing
4
Yes
Continue data
reception?
3
No
(A)
Clear bit RE to
0 in SCR3
End
Figure 10-13 Example of Data Reception Flowchart (Asynchronous Mode)
301
ETC [ ETC ]
