HD6433935 Hitachi, HD6433935 Datasheet - Page 97

• Manufacturer Part Number: HD6433935
• Description: 8-Bit MICROCONTROLLER
• Manufacturer: Hitachi

4.1
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.
4.1.1
Figure 4-1 shows a block diagram of the clock pulse generators.
OSC
OSC
4.1.2
The basic clock signals that drive the CPU and on-chip peripheral modules are ø and ø
the clock signals have names: ø is the system clock, ø
clock, ø
The clock signals available for use by peripheral modules are ø/2, ø/4, ø/8, ø/16, ø/32, ø/64, ø/128,
ø/256, ø/512, ø/1024, ø/2048, ø/4096, ø/8192, ø
and ø
DX
DX
1
2
1
2
DEC
w
. The clock requirements differ from one module to another.
System clock pulse generator
Subclock pulse generator
System clock
is the watch clock, and ø
Overview
Block Diagram
System Clock and Subclock
Subclock
oscillator
oscillator
Figure 4-1 Block Diagram of Clock Pulse Generators
Section 4 Clock Pulse Generators
Subclock
oscillator
(1/2)
(f
ø
OSC
OSC
)
DEC
ø
(f )
W
W
is the decoder clock.
System clock
(1/2, 1/4, 1/8)
divider (1/2)
Subclock
divider
W
, ø
W
ø
ø /2
ø /4
ø /8
/2, ø
OSC
SUB
W
W
W
/2
System
divider
is the subclock, ø
clock
W
/4, ø
W
/8, ø
ø
ø
ø
ø
OSC
OSC
OSC
OSC
/128
/64
/32
/16
W
/16, ø
OSC
W
is the oscillator
Prescaler W
/32, ø
Prescaler S
(13 bits)
ø
ø
(5 bits)
SUB
W
/64, ø
SUB
. Five of
W
ø/2
to
ø/8192
ø
ø /2
ø /4
ø /8
to
ø /128
ø
/128,
DEC
W
W
W
W
W
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