NXP Semiconductors KL25 Series - Page 130

6.2.2.4 Low leakage wakeup (LLWU)
The LLWU module provides the means for a number of external pins and a number of
internal peripherals to wake the MCU from low leakage power modes. The LLWU
module is functional only in low leakage power modes. In VLLSx modes, all enabled
inputs to the LLWU can generate a system reset.
After a system reset, the LLWU retains the flags indicating the input source of the last
wakeup until the user clears them.
NOTE
Some flags are cleared in the LLWU and some flags are
required to be cleared in the peripheral module. Refer to the
individual peripheral chapters for more information.
6.2.2.5 Multipurpose clock generator loss-of-clock (LOC)
The MCG module supports an external reference clock.
If the C6[CME] bit in the MCG module is set, the clock monitor is enabled. If the
external reference falls below f
loc_low
or f
loc_high
, as controlled by the C2[RANGE] field
in the MCG module, the MCU resets. The RCM's SRS0[LOC] bit is set to indicate this
reset source.
NOTE
To prevent unexpected loss of clock reset events, all clock
monitors must be disabled before entering any low power
modes, including VLPR and VLPW.
6.2.2.6 MCG loss-of-lock (LOL) reset
The MCG includes a PLL loss-of-lock detector. The detector is enabled when configured
for PEE and lock has been achieved. If the MCG_C8[LOLRE] bit in the MCG module is
set and the PLL lock status bit (MCG_S[LOLS0]) becomes set, the MCU resets. The
RCM_SRS0[LOL] bit is set to indicate this reset source.
NOTE
This reset source does not cause a reset if the chip is in any stop
mode.
Reset
KL25 Sub-Family Reference Manual, Rev. 3, September 2012
130 Freescale Semiconductor, Inc.