SH7014 Datasheet, PDF (388/754 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

12. Serial Communication Interface (SCI)
Start of initialization
Clear TE and RE bits to 0 in SCR
Set RIE, TIE, TEIE, MPIE, CKE1,
and CKE0 bits in SCR
1
(TE and RE are 0)
Select transmit/receive
format in SMR
2
Set value in BRR
Wait
1-bit interval elapsed?
3
No
Yes
Set TE and RE to 1 in SCR;
Set RIE, TIE, TEIE, and MPIE bits ⁴
End
Figure 12.15 Sample Flowchart for SCI Initialization
Transmitting Serial Data (Synchronous Mode): Figure 12.16 shows a sample flowchart for
transmitting serial data and indicates the procedure to follow.
1. SCI initialization: Set the TxD pin function with the PFC.
2. SCI status check and transmit data write: Read SSR, check that the TDRE flag is 1, then write
transmit data in TDR and clear the TDRE flag to 0.
3. To continue transmitting serial data: After checking that the TDRE flag is 1, indicating that
data can be written, write data in TDR, then clear the TDRE flag to 0. When the DMAC or
DTC is activated by a transmit-data-empty interrupt request (TXI) to write data in TDR, the
TDRE flag is checked and cleared automatically.
Rev.5.00 Sep. 27, 2007 Page 354 of 716
REJ09B0398-0500