Datasheet

Section 5 Clock Pulse Generator
Page 136 of 982 REJ09B0465-0300 Rev. 3.00
Sep 17, 2010
H8S/20103, H8S/20203, H8S/20223, H8S/20115, H8S/20215, H8S/20235 Group
5.4.2 Connecting Ceramic Resonator
Figure 5.14 shows an example of connecting a ceramic resonator. A damping resistor Rd should
be added, if necessary. Since the resistor values vary depending on the resonator, use values
recommended by the resonator manufacturer.
C
1
C
2
PJ0/OSC1
PJ1/OSC2/CLKOUT
C
1
= C
2
= 5 to 30 pF
Rd
Figure 5.14 Example of Connection to Ceramic Resonator
5.4.3 External Clock Input Method
To use the external clock, input the external clock on pin OSC1. Figure 5.15 shows an example of
connection. The duty cycle of the external clock signal must be 45 to 55%.
PJ0/OSC1
PJ1/OSC2/CLKOUT
External clock input
Open
Figure 5.15 Example of External Clock Input
Note: To input the external clock, set the PMRJ[1:0] bits to 01. Do not input the external clock
while PMRJ[1:0] bits are set to 11.