13.4.2.5 Transition from stop modes to Debug mode
The debugger module supports a transition from STOP, WAIT, VLPS, and VLPW back
to a Halted state when the debugger has been enabled. As part of this transition, system
clocking is re-established and is equivalent to the normal RUN and VLPR mode clocking
configuration.
13.4.3 Run modes
The device supports the following run modes:
• Run (RUN)
• Very Low-Power Run (VLPR)
13.4.3.1 RUN mode
This is the normal operating mode for the device.
This mode is selected after any reset. When the ARM processor exits reset, it sets up the
stack, program counter (PC), and link register (LR):
• The processor reads the start SP (SP_main) from vector-table offset 0x000
• The processor reads the start PC from vector-table offset 0x004
• LR is set to 0xFFFF_FFFF.
To reduce power in this mode, disable the clocks to unused modules using their
corresponding clock gating control bits in the SIM's registers.
13.4.3.2 Very-Low Power Run (VLPR) mode
In VLPR mode, the on-chip voltage regulator is put into a stop mode regulation state. In
this state, the regulator is designed to supply enough current to the MCU over a reduced
frequency. To further reduce power in this mode, disable the clocks to unused modules
using their corresponding clock gating control bits in the SIM's registers.
Before entering this mode, the following conditions must be met:
• The MCG must be configured in a mode which is supported during VLPR. See the
Power Management details for information about these MCG modes.
• All clock monitors in the MCG must be disabled.
Chapter 13 System Mode Controller (SMC)
KL02 Sub-Family Reference Manual, Rev. 2.1, July 2013
Freescale Semiconductor, Inc.
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