Chapter 11 S12XE Clocks and Reset Generator (S12XECRGV1)
MC9S12XE-Family Reference Manual , Rev. 1.19
496
Freescale Semiconductor
11.6.1
Description of Interrupt Operation
11.6.1.1
Real Time Interrupt
The S12XECRG generates a real time interrupt when the selected interrupt time period elapses. RTI
interrupts are locally disabled by setting the RTIE bit to zero. The real time interrupt flag (RTIF) is set to1
when a timeout occurs, and is cleared to 0 by writing a 1 to the RTIF bit.
The RTI continues to run during Pseudo Stop Mode if the PRE bit is set to 1. This feature can be used for
periodic wakeup from Pseudo Stop if the RTI interrupt is enabled.
11.6.1.2
IPLL Lock Interrupt
The S12XECRG generates a IPLL Lock interrupt when the LOCK condition of the IPLL has changed,
either from a locked state to an unlocked state or vice versa. Lock interrupts are locally disabled by setting
the LOCKIE bit to zero. The IPLL Lock interrupt flag (LOCKIF) is set to1 when the LOCK condition has
changed, and is cleared to 0 by writing a 1 to the LOCKIF bit.
11.6.1.3
Self Clock Mode Interrupt
The S12XECRG generates a Self Clock Mode interrupt when the SCM condition of the system has
changed, either entered or exited Self Clock Mode. SCM conditions are caused by a failing clock quality
check after power on reset (POR) or low voltage reset (LVR) or recovery from Full Stop Mode (PSTP =
0) or Clock Monitor failure. For details on the clock quality check refer to
Section 11.4.1.4, “Clock Quality
. If the clock monitor is enabled (CME = 1) a loss of external clock will also cause a SCM
condition (SCME = 1).
SCM interrupts are locally disabled by setting the SCMIE bit to zero. The SCM interrupt flag (SCMIF) is
set to1 when the SCM condition has changed, and is cleared to 0 by writing a 1 to the SCMIF bit.
Because
of
an
order
from
the
United
States
International
Trade
Commission,
BGA-packaged
product
lines
and
part
numbers
indicated
here
currently
are
not
available
from
Freescale
for
import
or
sale
in
the
United
States
prior
to
September
2010:
S12XE
products
in
208
MAPBGA
packages
