SH7144_08 Datasheet, PDF (499/930 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperHTM RISC engine Family/SH7144 Series

13. Serial Communication Interface (SCI)
13.7.5 Initialization
Before transmitting and receiving data, initialize the SCI as described below. Initialization is also
necessary when switching from transmit mode to receive mode, or vice versa.
1. Clear the RIE, TIE, TEIE, MPIE, TE, and RE bits in SCR to 0.
2. Clear the error flags ERS, PER, and ORER in SSR to 0.
3. Set the GM, BLK, O/E, BCP1, BCP0, CKS1, and CKS0 bits in SMR. Set the PE bit to 1.
4. Set the SMIF, DIR, and SINV bits in SDCR.
5. Set the value corresponding to the bit rate to BRR.
6. Set the CKE1 and CKE0 bits in SCR. Clear the TIE, RIE, TE, RE, MPIE, and TEIE bits to 0.
7. Wait at least one bit interval, then set the TIE and RIE bits in SCR.
8. Make the pin function settings for the external pins (SCK, TxD, and RxD).
9. Set the TE and RE bits in SCR. Except for self diagnosis, do not set the TE bit and RE bit at
the same time.
To switch from receive mode to transmit mode, after checking that the SCI has finished reception,
initialize the SCI, and clear the RE bit to 0 and set the TE bit to 1. Whether the SCI has finished
reception or not can be checked with the RDRF, PER, or ORER flag. To switch from transmit
mode to receive mode, after checking that the SCI has finished transmission, initialize the SCI,
and clear the TE bit to 0 and set the RE bit to 1. Whether the SCI has finished transmission or not
can be checked with the TEND flag.
Rev.4.00 Mar. 27, 2008 Page 455 of 882
REJ09B0108-0400