Section 5 Power-Down Modes; Overview - Renesas H8/38024 Hardware Manual

5.1

Overview

The LSI has nine modes of operation after a reset. These include eight power-down modes, in
which power dissipation is significantly reduced. Table 5.1 gives a summary of the nine operating
modes.
Table 5.1 Operating Modes
Operating Mode
Active (high-speed) mode
Active (medium-speed) mode
Subactive mode
Sleep (high-speed) mode
Sleep (medium-speed) mode
Subsleep mode
Watch mode
Standby mode
Module standby mode
Of these nine operating modes, all but the active (high-speed) mode are power-down modes. In
this section the two active modes (high-speed and medium speed) will be referred to collectively
as active mode.

Section 5 Power-Down Modes

Description
The CPU and all on-chip peripheral functions are operable on
the system clock in high-speed operation
The CPU and all on-chip peripheral functions are operable on
the system clock in low-speed operation
The CPU is operable on the subclock in low-speed operation
The CPU halts. On-chip peripheral functions are operable on
the system clock
The CPU halts. On-chip peripheral functions operate at a
frequency of 1/128, 1/64, 1/32, or 1/16 of the system clock
frequency
The CPU halts. The time-base function of timer A, timer C,
timer F, timer G, SCI3, AEC, and LCD controller/driver are
operable on the subclock
The CPU halts. The time-base function of timer A, timer F,
timer G, AEC and LCD controller/driver are operable on the
subclock
The CPU and all on-chip peripheral functions halt
Individual on-chip peripheral functions specified by software
enter standby mode and halt
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