H8S2339 Datasheet, PDF (659/1244 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2300 Series

Section 14 Serial Communication Interface (SCI)
Figure 14.4 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, MPIE, 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 14.4 Sample SCI Initialization Flowchart
Rev.4.00 Sep. 07, 2007 Page 629 of 1210
REJ09B0245-0400