D12320VF25IV Datasheet, PDF (951/1304 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 21 Power-Down Modes
Section 21 Power-Down Modes
21.1 Overview
In addition to the normal program execution state, the chip has five power-down modes 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 chip operating modes are as follows:
1. High-speed mode
2. Medium-speed mode
3. Sleep mode
4. Module stop mode
5. Software standby mode
6. Hardware standby mode
Of these, 2 to 6 are power-down modes. Sleep mode is a CPU mode, medium-speed mode is a
CPU and bus master mode, and module stop mode is an on-chip supporting module mode
(including bus masters other than the CPU). A combination of these modes can be set.
After a reset, the chip is in high-speed mode.
Table 21.1 shows the conditions for transition to the various modes, the status of the CPU, on-chip
supporting modules, etc., and the method of clearing each mode.
Rev.6.00 Sep. 27, 2007 Page 919 of 1268
REJ09B0220-0600