HD64F3028F25 Datasheet, PDF (517/925 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

Figure 13.4 shows a sample flowchart for initializing the SCI.
Start of initialization
Clear TE and RE bits
to 0 in SCR
Set CKE1 and CKE0 bits in SCR
(leaving TE and RE bits
(1)
cleared to 0)
Select communication format ₍₂₎
in SMR
Set value in BRR
(3)
Wait
No
1-bit interval elapsed?
Yes
Set TE or RE bit to 1 in SCR (4)
Set the RIE, TIE, TEIE, and
MPIE bits
(1) Set the clock source in SCR. Clear the
RIE, TIE, TEIE, MPIE, TE, and RE bits to
0. If clock output is selected in
asynchronous mode, clock output starts
immediately after the setting is made in
SCR.
(2) Select the communication format in SMR.
(3) Write the value corresponding to the bit
rate in BRR.
This step is not necessary when an
external clock is used.
(4) Wait for at least the interval required to
transmit or receive one bit, then set the
TE or RE bit to 1 in SCR. Set the RIE,
TIE, TEIE, and MPIE bits as necessary.
Setting the TE or RE bit enables the SCI
to use the TxD or RxD pin.
<End of initialization>
Note: In simultaneous transmitting and receiving, the TE and RE bits should be cleared to
0 or set to 1 simultaneously.
Figure 13.4 Sample Flowchart for SCI Initialization
Rev. 2.00, 09/03, page 485 of 890