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Functional Description
The latter method of exiting from low-power mode, by a valid and enabled interrupt
request, requires several things:
• An interrupt request whose priority is higher than the value programmed in the
XLPM_IPL field of the LPICR
• An interrupt request whose priority higher than the value programmed in the
interrupt priority mask (I) field of the core's status register
• An interrupt request from a source which is not masked in the interrupt controller's
interrupt mask register
• An interrupt request which has been enabled at the module of the interrupt's origin
7.3.1.1
Run Mode
Run mode is the normal system operating mode. Current consumption in this mode is
related directly to the system clock frequency.
7.3.1.2
Wait Mode
Wait mode is intended to be used to stop only the CPU and memory clocks until a wakeup
event is detected. In this mode, peripherals may be programmed to continue operating and
can generate interrupts, which cause the CPU to exit from wait mode.
7.3.1.3
Doze Mode
Doze mode affects the CPU in the same manner as wait mode, except that each peripheral
defines individual operational characteristics in doze mode. Peripherals which continue to
run and have the capability of producing interrupts may cause the CPU to exit the doze
mode and return to run mode. Peripherals which are stopped will restart operation on exit
from doze mode as defined for each peripheral.
7.3.1.4
Stop Mode
Stop mode affects the CPU in the same manner as the wait and doze modes, except that all
clocks to the system are stopped and the peripherals cease operation.
Stop mode must be entered in a controlled manner to ensure that any current operation is
properly terminated. When exiting stop mode, most peripherals retain their pre-stop status
and resume operation.
The following subsections specify the operation of each module while in and when exiting
low-power modes.
7-6
MCF5282 User's Manual
MOTOROLA
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