D12320VF25V Datasheet, PDF (499/1146 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 12 Serial Communication Interface (SCI)
Figure 12.4 shows a sample SCI initialization flowchart.
Start of 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 or RE bit in
SCR to 1, and set RIE, TIE, TEIE,
[4]
and MPIE bits as necessary
[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 as necessary.
Setting the TE or RE bit enables
the TxD or RxD pin to be used.
<Initialization completed>
Figure 12.4 Sample SCI Initialization Flowchart
Rev.7.00 Feb. 14, 2007 page 465 of 1108
REJ09B0089-0700