h8s-2138 Renesas Electronics Corporation., h8s-2138 Datasheet - Page 735

• Manufacturer Part Number: h8s-2138
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 24 Power-Down State
Section 24 Power-Down State
24.1
Overview
In addition to the normal program execution state, the H8S/2138 Group and H8S/2134 Group have
a power-down state in which operation of the CPU and oscillator is halted and power dissipation
is reduced. Low-power operation can be achieved by individually controlling the CPU, on-chip
supporting modules, and so on.
The H8S/2138 Group and H8S/2134 Group operating modes are as follows:
1. High-speed mode
2. Medium-speed mode
3. Subactive mode
4. Sleep mode
5. Subsleep mode
6. Watch mode
7. Module stop mode
8. Software standby mode
9. Hardware standby mode
Of these, 2 to 9 are power-down modes. Sleep mode and subsleep mode are CPU modes, medium-
speed mode is a CPU and bus master mode, subactive mode is a CPU, bus master, and on-chip
supporting module mode, and module stop mode is an on-chip supporting module mode
(including bus masters other than the CPU). Certain combinations of these modes can be set.
After a reset, the MCU is in high-speed mode and module stop mode (excluding the DTC).
Table 24.1 shows the internal chip states in each mode, and table 24.2 shows the conditions for
transition to the various modes. Figure 24.1 shows a mode transition diagram.
Rev. 4.00 Jun 06, 2006 page 681 of 1004
REJ09B0301-0400