Datasheet

Section 16 Serial Communication Interface (SCI, IrDA)
(The H8S/2695 is not equipped with an IrDA function)
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Mar 02, 2011
H8S/2633 Group, H8S/2633 F-ZTAT
TM
,
H8S/2633R F-ZTAT
TM
, H8S/2695
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. For details of SCI clock source selection, see table
16.9.
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 16.3.
0
1 frame
D0 D1 D2 D3 D4 D5 D6 D7 0/1 1 1
Figure 16.3 Relation between Output Clock and Transfer Data Phase
(Asynchronous Mode)