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Preliminary User’s Manual U16035EJ1V0UM
CHAPTER 5 CLOCK GENERATOR
5.1 Functions of Clock Generator
The clock generator generates the clock to be supplied to the CPU and peripheral hardware. The following two
types of system clock oscillators are available.
(1) Main system clock oscillator
This circuit oscillates at frequencies of 1 to 8.38 MHz. Oscillation can be stopped by executing the STOP
instruction or setting the processor clock control register (PCC).
(2) Subsystem clock oscillator
The circuit oscillates at a frequency of 32.768 kHz. Oscillation cannot be stopped. If the subsystem clock oscillator
is not used, the internal feedback resistor can be disabled by the processor clock control register (PCC). This
enables to reduce the power consumption in the STOP mode.
5.2 Configuration of Clock Generator
The clock generator consists of the following hardware.
Table 5-1. Configuration of Clock Generator
Item
Configuration
Control register
Processor clock control register (PCC)
Oscillators
Main system clock oscillator
Subsystem clock oscillator
