HD64F3644PV Datasheet, PDF (345/551 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 10 Serial Communication Interface
Clock: Either an internal clock generated by the baud rate generator or an external clock input at
the SCK₃ pin can be selected as the SCI3 serial clock. The selection is made by means of bit COM
in SMR and bits CKE1 and CKE0 in SCR3. See table 10.12 for details on clock source selection.
When SCI3 operates on an internal clock, the serial clock is output at the SCK₃ pin. Eight pulses
of the serial clock are output in transmission or reception of one character, and when SCI3 is not
transmitting or receiving, the clock is fixed at the high level.
Data Transfer Operations
SCI3 Initialization: Data transfer on SCI3 first of all requires that SCI3 be initialized as described
in 10.3.4, SCI3 Initialization, and shown in figure 10.10.
Transmitting: Figure 10.16 shows an example of a flowchart for data transmission. This
procedure should be followed for data transmission after initializing SCI3.
Rev. 6.00 Sep 12, 2006 page 323 of 526
REJ09B0326-0600