Datasheet

S12 Clock, Reset and Power Management Unit (S12CPMU)
MC9S12G Family Reference Manual, Rev.1.23
408 Freescale Semiconductor
10.4.4 Full Stop Mode using Oscillator Clock as Bus Clock
An example of what happens going into Full Stop Mode and exiting Full Stop Mode after an interrupt is
shown in Figure 10-32.
Disable PLL Lock interrupt (LOCKIE=0) and oscillator status change interrupt (OSCIE=0) before going
into Full Stop Mode.
Figure 10-32. Full Stop Mode using Oscillator Clock as Bus Clock
CPU
UPOSC
t
lock
STOP instruction
execution
interrupt continue execution
wakeup
t
STP_REC
Core
Clock
select OSCCLK as Core/Bus Clock by writing PLLSEL to “0”
PLLSEL
automatically set when going into Full Stop Mode
OSCCLK
PLLCLK