XC886/888CLM
Power Saving Modes
User’s Manual
8-1
V1.3, 2010-02
Power Saving Modes, V 1.0
8
Power Saving Modes
The power saving modes in the XC886/888 provide flexible power consumption through
a combination of techniques, including:
•
Stopping the CPU clock
•
Stopping the clocks of individual system components
•
Reducing clock speed of some peripheral components
•
Power-down of the entire system with fast restart capability
After a reset, the active mode (normal operating mode) is selected by default (see
) and the system runs in the main system clock frequency. From active mode,
different power saving modes can be selected by software. They are:
•
Idle mode
•
Slow-down mode
•
Power-down mode
Figure 8-1
Transition between Power Saving Modes
POWER-DOWN
IDLE
ACTIVE
SLOW-DOWN
set PD
bit
set PD
bit
set IDLE
bit
set IDLE
bit
set SD
bit
clear SD
bit
any interrupt
& SD=0
EXINT0/RXD pin
& SD=0
EXINT0/RXD pin
& SD=1
any interrupt
& SD=1
*