HD6432633 Datasheet, PDF (783/1453 Pages) Renesas Technology Corp – Series of Microcomputers (MCUs: microcomputer units)

Figure 16-4 shows a sample SCI initialization flowchart.
Start initialization
Clear TE and RE bits in SCR to 0
Set CKE1 and CKE0 bits in SCR
[1]
(TE, RE bits 0)
Set data transfer format in
SMR and SCMR
Set value in BRR
Wait
1-bit interval elapsed?
Yes
[2]
[3]
No
Set TE and RE bits in
SCR to 1, and set RIE, TIE, TEIE,
[4]
and MPIE bits
[1] Set the clock selection in SCR.
Be sure to clear bits RIE, TIE,
TEIE, and MPIE, and bits TE and
RE, to 0.
When the clock is selected in
asynchronous mode, it is output
immediately after SCR settings are
made.
[2] Set the data transfer format in SMR
and SCMR.
[3] Write a value corresponding to the
bit rate to BRR. Not necessary if an
external clock is used.
[4] Wait at least one bit interval, then
set the TE bit or RE bit in SCR to 1.
Also set the RIE, TIE, TEIE, and
MPIE bits.
Setting the TE and RE bits enables
the TxD and RxD pins to be used.
<Transfer completion>
Figure 16-4 Sample SCI Initialization Flowchart
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