Renesas H8 Series Hardware Manual

Section 4 Clock Pulse Generators
Rev. 7.00 Mar 10, 2005 page 103 of 652
REJ09B0042-0700
Section 4 Clock Pulse Generators
4.1 Overview
Clock oscillator circuitry (CPG: clock pulse generator) is provided on-chip, including both a
system clock pulse generator and a subclock pulse generator. The system clock pulse generator
consists of a system clock oscillator and system clock dividers. The subclock pulse generator
consists of a subclock oscillator circuit and a subclock divider.
In the H8/38124 Group, the system clock pulse generator includes an on-chip oscillator.
4.1.1 Block Diagram
Figure 4.1 shows a block diagram of the clock pulse generators of the H8/38024, H8/38024S, and
H8/38024R Group. Figure 4.2 shows a block diagram of the clock pulse generators of the
H8/38124 Group.
System clock
oscillator
System clock
divider (1/2)
Subclock
oscillator
Subclock
divider
(1/2, 1/4, 1/8)
System
clock
divider
System clock pulse generator
Subclock pulse generator
Prescaler S
(13 bits)
Prescaler W
(5 bits)
OSC
OSC
1
2
X
X
1
2
φ
OSC
( f
OSC
)
φ
W
φ
W
( f
W
)
φ
OSC
/2
φ
W
/2
φ
W
/8
φ
SUB
φ/2
to
φ/8192
φ
W
/2
φ
W
/4
φ
W
/8
to
φ
W
/128
φ
φ
OSC
/128
φ
OSC
/64
φ
OSC
/32
φ
OSC
/16
φ
W
/4
Figure 4.1(1) Block Diagram of Clock Pulse Generators
(H8/38024 Group, H8/38024S Group, H8/38024R Group)

Renesas H8 Series Specifications

General

Brand	Renesas
Model	H8 Series
Category	Computer Hardware
Language	English