13.4.5.3 Very-Low-Leakage Stop (VLLSx) modes
This device contains these very low leakage modes:
• VLLS3
• VLLS1
• VLLS0
VLLSx is often used in this document to refer to all of these modes.
All VLLSx modes can be entered from normal RUN or VLPR modes.
The MCU enters the configured VLLS mode if:
• In Sleep-Now or Sleep-On-Exit mode, the SLEEPDEEP bit is set in the System
Control Register in the ARM core, and
• The device is configured as shown in
.
In VLLS, the on-chip voltage regulator is in its stop-regulation state while most digital
logic is powered off.
When entering VLLS, each I/O pin is latched as configured before executing VLLS.
Because all digital logic in the MCU is powered off, all port and peripheral data is lost
during VLLS. This information must be restored before the ACKISO bit in the PMC is
set.
An asserted RESET pin will cause an exit from any VLLS mode, returning the device to
normal RUN mode. When exiting VLLS via the RESET pin, the PIN and WAKEUP bits
are set in the SRS0 register of the reset control module (RCM).
13.4.6 Debug in low power modes
When the MCU is secure, the device disables/limits debugger operation. When the MCU
is unsecure, the ARM debugger can assert two power-up request signals:
• System power up, via SYSPWR in the Debug Port Control/Stat register
• Debug power up, via CDBGPWRUPREQ in the Debug Port Control/Stat register
When asserted while in RUN, WAIT, VLPR, or VLPW, the mode controller drives a
corresponding acknowledge for each signal, that is, both CDBGPWRUPACK and
CSYSPWRUPACK. When both requests are asserted, the mode controller handles
attempts to enter STOP and VLPS by entering an emulated stop state. In this emulated
stop state:
• the regulator is in run regulation,
• the MCG-generated clock source is enabled,
Chapter 13 System Mode Controller (SMC)
KL02 Sub-Family Reference Manual, Rev. 2.1, July 2013
Freescale Semiconductor, Inc.
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