Panasonic MN101C77C Manual De Usuario

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Chapter 2 CPU Basics

Standby Functions

2-4

Standby Function

2-4-1

Overview

This LSI has two sets of system clock oscillator (high speed oscillation, low speed oscillation) for two

CPU operating modes (NORMAL and SLOW), each with two standby modes (HALT and STOP). Power

consumption can be decreased with using those modes.

IDLE

OSC: Halt
XI: Oscillation

OSC: Oscillation
XI: Oscillation

NORMAL

SLOW

Program 4

Program 5

Interrupt

Program 5

Interrupt

Program 4

Interrupt

OSC: Oscillation

Program 2

Program1

Reset

STOP0
OSC: Halt
XI : Halt

STOP mode

NORMAL mode

SLOW mode

Program 3

HALT mode

HALT 0

OSC: Oscillation
Xl: Oscillation

CPU operation mode

STANDBY mode

STOP1
OSC: Halt
XI: Halt

HALT 1

OSC: Halt
XI: Oscillation

:CPU halt

: Wait period for oscillation stabilization is inserted OSC: High-frequency oscillation clock

XI: Low-frequency oscillation clock (32 kHz)

XI: Oscillation

Figure 2-4-1 Transition Between Operation Modes