HD64336900G Datasheet, PDF (93/408 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Tiny Series

Section 5 Clock Pulse Generators
Clock oscillator circuitry (CPG: clock pulse generator) consists of an external oscillator, an
internal RC oscillator, a duty correction circuit, a clock select circuit, and system clock dividers.
Figure 5.1 shows a block diagram of the clock pulse generator.
OSC1
System
clock
φ_OSC
Duty
φ_OSC
correction
φ
OSC2
oscillator
circuit
φ/8
φ_RC
Internal
RC
φ_{RC RC clock φRC/2}
φ_RC
oscillator
divider
φ_RC/4
Clock _φ System _φ/16
select
circuit
clock
divider ^φ/32
φ/64
φ
Prescaler S
(13 bits)
φ/2
to
φ/8192
Figure 5.1 Block Diagram of Clock Pulse Generators
The system clock (φ) is a basic clock on which the CPU and on-chip peripheral modules operate.
The system clock is divided into φ/2 to φ/8192 by prescaler S and the divided clocks are supplied
to respective peripheral modules.
CPG0200A_000020020200
Rev. 1.00, 11/03, page 65 of 376