h8s-2158 Renesas Electronics Corporation., h8s-2158 Datasheet - Page 814

• Manufacturer Part Number: h8s-2158
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 26 Clock Pulse Generator
The subclock input is controlled by software according to the EXCLE bit setting in the low power
control register. For details on the low power control register, see section 27.1.2, Low-Power
Control Register (LPWRCR).
26.1
Clock pulses can be supplied either by connecting a crystal resonator or by providing external
clock input.
26.1.1
Figure 26.2 shows a typical method of connecting a crystal resonator. An appropriate damping
resistance R
should be used.
Figure 26.3 shows the equivalent circuit of a crystal resonator. A crystal resonator having the
characteristics given in table 26.2 should be used.
A crystal resonator with frequency identical to that of the system clock ( ) should be used.
Table 26.1 Damping Resistance Values
Rev. 3.00 Jan 25, 2006 page 762 of 872
REJ09B0286-0300
Frequency (MHz)
R
d
( )
Oscillator
Connecting a Crystal Oscillator
d
, given in table 26.1, should be used. An AT-cut parallel-resonance crystal resonator
XTAL
Figure 26.2 Typical Connection to Crystal Resonator
Figure 26.3 Equivalent Circuit of Crystal Resonator
5
300
EXTAL
XTAL
L
R
8
200
d
C
C
L
0
C
C
AT-cut parallel-resonance crystal resonator
L1
L2
R
10
0
s
EXTAL
12
0
C
L1
= C
L2
= 10 to 22 pF
16
0
20
0
25
0