Chapter 3 Modes of Operation
MC9S08QE128 MCU Series Reference Manual, Rev. 2
48
Freescale Semiconductor
3.7.1
On-Chip Peripheral Modules in Stop and Low Power Modes
When the MCU enters any stop mode, system clocks to the internal peripheral modules are stopped. Even
in the exception case (ENBDM = 1), where clocks to the background debug logic continue to operate,
clocks to the peripheral systems are halted to reduce power consumption. Refer to
,” and
,” for specific information on system behavior in stop modes.
When the MCU enters LPWait or LPRun modes, system clocks to the internal peripheral modules continue
based on the settings of the clock gating control registers (SCGC1 and SCGC2).
5
LPWAIT
RUN
Interrupt when LPWUI=1
RUN
LPWAIT
NOT SUPPORTED
6
RUN
WAIT
WAIT instruction
WAIT
RUN
Interrupt or reset
7
STOP3
RUN
Interrupt (if LPR = 0, or LPR = 1 and LPWUI =1)
or reset
RUN
STOP3
STOP instruction
1
An analog connection from this pin to the on-chip regulator will wake up the regulator, which will then initiate a
power-on-reset sequence.
Table 3-4. Stop and Low Power Mode Behavior
Peripheral
Mode
Stop2
Stop3
LPWait
LPRun
CPU
Off
Standby
Standby
On
RAM
Standby
Standby
Standby
On
Flash
Off
Standby
Standby
On
Port I/O Registers
Off
Standby
Standby
On
Port I/O Pins
States Held
Peripheral Control
Peripheral Control
On
ADC
Off
Optionally On
1
Optionally On
1
Optionally On
1
ACMPx
Off
Optionally On
2
Optionally On
Optionally On
BDM
Off
3
Optionally On
Off
4
COP
Off
Off
Optionally On
Optionally On
ICS
Off
Optionally On
5
On
6
IICx
Off
Standby
Optionally On
Optionally On
IRQ
Wake Up
Optionally On
Optionally On
Optionally On
KBIx
Off
Optionally On
Optionally On
Optionally On
LVD/LVW
Off
7
Optionally On
Off
8
RTC
Optionally On
Optionally On
Optionally On
Optionally On
Table 3-3. Triggers for Transitions Shown in
Figure 3-1
. (continued)
Transition #
From
To
Trigger
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