HD6412373R RENESAS [Renesas Technology Corp], HD6412373R Datasheet - Page 794

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

Section 15 Serial Communication Interface (SCI, IrDA)
15.4.3
Clock
Either an internal clock generated by the on-chip baud rate generator or an external clock input at
the SCK pin can be selected as the SCI’s serial clock, according to the setting of the C/A bit in
SMR and the CKE1 and CKE0 bits in SCR. When an external clock is input at the SCK pin, the
clock frequency should be 16 times the bit rate used.
When the SCI is operated on an internal clock, the clock can be output from the SCK pin. The
frequency of the clock output in this case is equal to the bit rate, and the phase is such that the
rising edge of the clock is in the middle of the transmit data, as shown in figure 15.4.
SCK
0
D0
D1
D2
D3
D4
D5
D6
D7
0/1
1
1
TxD
1 frame
Figure 15.4 Relation between Output Clock and Transfer Data Phase
(Asynchronous Mode)
Rev.7.00 Mar. 18, 2009 page 726 of 1136
REJ09B0109-0700