MC9S08GB60A Datasheet, PDF (120/302 Pages) Freescale Semiconductor, Inc – HCS08 Microcontrollers

Internal Clock Generator (S08ICGV2)
ICGC2 = $30 (%00110000)
Bit 7 LOLRE
Bit 6:4 MFD
Bit 3 LOCRE
Bit 2:0 RFD
0 Generates an interrupt request on loss of lock
011 Sets the MFD multiplication factor to 10
0 Generates an interrupt request on loss of clock
000 Sets the RFD division factor to ÷1
ICGS1 = $xx
This is read only except for clearing interrupt flag
ICGS2 = $xx
This is read only. Should read DCOS before performing any time critical tasks
ICGFLTLU/L = $xx
Not used in this example
ICGTRM
Not used in this example
RECOVERY FROM
RESET, STOP1, STOP2
RECOVERY
FROM STOP3
INITIALIZE ICG
ICG1 = $7A
ICG2 = $30
SERVICE INTERRUPT
SOURCE (f_Bus = 4 MHz)
CHECK
NO
FLL LOCK STATUS
LOCK = 1?
YES
CONTINUE
CHECK
FLL LOCK STATUS ^NO
LOCK = 1?
YES
CONTINUE
Figure 7-9. ICG Initialization and Stop Recovery for Example #2
MC9S08GB60A Data Sheet, Rev. 2
120
Freescale Semiconductor