Hitachi H8/3937 Series Hardware Manual page 100

4. External clock input method
Connect an external clock signal to pin OSC
typical connection.
OSC
OSC
Frequency
Duty cycle
Caution
When a crystal or ceramic oscillator element is connected, circuit constants will differ according
to the oscillator element, installation circuit stray capacitance, and so forth, and so should be
determined in consultation with the crystal or ceramic oscillator element manufacturer.
88
, and leave pin OSC
1
1
Open
2
Figure 4-6 External Clock Input (Example)
open. Figure 4-6 shows a
2
External clock input
Oscillator Clock (ø
OSC
45% to 55%
)