SH7018 datasheet(246/431 Pages) RENESAS

246 / 431 page

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Initialize

Clear TE and RE bits to 0 in SCR1

Set CKE1 and CKE0 bits in SCR1

(TE and RE bits are 0)

Select transmit/receive format in SMR1

Set value to BRR1

Wait

Set TE or RE to 1 in SCR1; Set RIE,

TIE, TEIE, and MPIE as necessary

1-bit interval elapsed?

End

(1)

(2)

(3)

(4)

Yes

Figure 12.4 Sample Flowchart for SCI1 Initialization

Transmitting Serial Data (Asynchronous Mode): Figure 12.5 shows a sample flowchart for

transmitting serial data. The procedure is as follows (the steps correspond to the numbers in the

flowchart):

1. SCI1 initialization: Set the TxD pin using the PFC.

2. SCI1 status check and transmit data write: Read the serial status register (SSR1), check that the

TDRE bit is 1, then write transmit data in the transmit data register (TDR1) and clear TDRE

to 0.

3. Continue transmitting serial data: Read the TDRE bit to check whether it is safe to write (if it

reads 1); if so, write data in TDR1, then clear TDRE to 0.

4. To output a break at the end of serial transmission, first clear the port data register (DR) to 0,

then clear the TE to 0 in SCR1 and use the PFC to establish the TxD pin as an output port.

SH7018 Datasheet(PDF) 246 Page - Renesas Technology Corp