MC912D60ACPVE8 Datasheet, PDF (151/460 Pages) Freescale Semiconductor, Inc – MC68HC912D60A MC68HC912D60C MC68HC912D60P Technical Data

Clock Functions
Limp-Home and Fast STOP Recovery modes
improper EXTALi clock cycles can occur on SYSCLK. This may lead to
a code runaway.
11.6.7 STOP exit in Limp Home mode without Delay (Fast Stop Recovery)
(NOLHM=0, CME=X, DLY=0)
Fast STOP recovery refers to any exit from STOP using DLY=0.
If the NOLHM bit is cleared, then the CME (or FCME) bit is masked when
a STOP instruction is executed to prevent a clock monitor failure. When
coming out of STOP mode, the MCU goes into limp-home mode where
CME and FCME signals are asserted.
When using a crystal oscillator, it is possible to exit STOP with the DLY
bit cleared. In this case, STOP is de-asserted without delay and the MCU
will execute software in limp-home mode, giving the crystal oscillator
time to stablise.
CAUTION: This mode is not recommended since the risk of the clock monitor
detecting incorrect clocks is high.
MC68HC912D60A — Rev. 3.1
Freescale Semiconductor
Clock Functions
Technical Data
151