h8s-2138 Renesas Electronics Corporation., h8s-2138 Datasheet - Page 728

• Manufacturer Part Number: h8s-2138
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 23 Clock Pulse Generator
23.3.2
Circuit Configuration: An external clock signal can be input as shown in the examples in figure
23.5. If the XTAL pin is left open, make sure that stray capacitance is no more than 10 pF.
In example (b), make sure that the external clock is held high in standby mode, subactive mode,
subsleep mode, and watch mode.
External Clock: The external clock signal should have the same frequency as the system clock
( ).
Table 23.4 and figure 23.6 show the input conditions for the external clock.
Rev. 4.00 Jun 06, 2006 page 674 of 1004
REJ09B0301-0400
External Clock Input
EXTAL
XTAL
EXTAL
XTAL
Figure 23.5 External Clock Input (Examples)
(b) Complementary clock input at XTAL pin
(a) XTAL pin left open
Open
External clock input
External clock input