HD6412373R RENESAS [Renesas Technology Corp], HD6412373R Datasheet - Page 795

• Manufacturer Part Number: HD6412373R
• Description: Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2300 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

15.4.4
Before transmitting and receiving data, you should first clear the TE and RE bits in SCR to 0, then
initialize the SCI as shown in figure 15.5. Do not write to SMR, SCMR, IrCR, or SEMR while the
SCI is operating. This also applies to writing the same data as the current register contents. When
the operating mode, transfer format, etc., is changed, the TE and RE bits must be cleared to 0
before making the change. When the TE bit is cleared to 0, the TDRE flag is set to 1. Note that
clearing the RE bit to 0 does not initialize the contents of the RDRF, PER, FER, and ORER flags,
or the contents of RDR. When the external clock is used in asynchronous mode, the clock must be
supplied even during initialization.
Set CKE1 and CKE0 bits in SCR
SCR to 1, and set RIE, TIE, TEIE,
Clear TE and RE bits in SCR to 0
SCI Initialization (Asynchronous Mode)
Set data transfer format in
<Initialization completed>
1-bit interval elapsed?
Set TE and RE bits in
Start of initialization
SMR and SCMR
Set value in BRR
(TE, RE bits 0)
and MPIE bits
Figure 15.5 Sample SCI Initialization Flowchart
Yes
Wait
No
Section 15 Serial Communication Interface (SCI, IrDA)
[1]
[2]
[3]
[4]
[1] Set the clock selection in SCR.
[2] Set the data transfer format in SMR
[3] Write a value corresponding to the
[4] Wait at least one bit interval, then
Rev.7.00 Mar. 18, 2009 page 727 of 1136
Be sure to clear bits RIE, TIE,
TEIE, and MPIE, and bits TE and
RE, to 0.
When the clock is selected in
asynchronous mode, it is output
immediately after SCR settings are
made.
and SCMR.
bit rate to BRR. (Not necessary if
an external clock is used.)
set the TE bit or RE bit in SCR to 1.
Also set the RIE, TIE, TEIE, and
MPIE bits.
Setting the TE and RE bits enables
the TxD and RxD pins to be used.
REJ09B0109-0700