HD6412373R RENESAS [Renesas Technology Corp], HD6412373R Datasheet - Page 1023

• Manufacturer Part Number: HD6412373R
• Description: Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2300 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

This LSI has an on-chip clock pulse generator (CPG) that generates the system clock (
internal clocks.
The clock pulse generator consists of an oscillator circuit, PLL circuit, and divider.
Figure 23.1 shows a block diagram of the clock pulse generator.
The frequency can be changed by means of the PLL circuit. Frequency changes are made by
software by means of settings in the PLL control register (PLLCR) and the system clock control
register (SCKCR).
23.1
The clock pulse generator has the following registers.
• System clock control register (SCKCR)
• PLL control register (PLLCR)
23.1.1
SCKCR controls
used by the PLL circuit is changed, and the division ratio used by the divider.
CPG0400A_010020020400
Legend:
PLLCR: PLL system control register
SCKCR: System clock control register
EXTAL
XTAL
Register Descriptions
System Clock Control Register (SCKCR)
Oscillator
φ
clock output and selects operation when the frequency multiplication factor
Figure 23.1 Block Diagram of Clock Pulse Generator
Section 23 Clock Pulse Generator
PLL circuit
(×1, 2, 4)
PLLCR
STC0, STC1
Rev.7.00 Mar. 18, 2009 page 955 of 1136
Divider
SCKCR
SCK2 to SCK0
Section 23 Clock Pulse Generator
System clock
to φ pin
REJ09B0109-0700
Internal clock
to peripheral
modules
φ
) and