mc68hc908ey16a Freescale Semiconductor, Inc, mc68hc908ey16a Datasheet - Page 94

• Manufacturer Part Number: mc68hc908ey16a
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Internal Clock Generator (ICG) Module
The external clock stable bit (ECGS) is also generated in the external clock activity detector. ECGS is set
on a falling edge of the external stabilization clock (ESTBCLK). This will be 4096 ECLK cycles after the
external clock generator on bit is set, or the MCU exits stop mode (ECGEN = 1) if the external crystal
enable (EXTXTALEN) in the CONFIG is set, or 16 cycles when EXTXTALEN is clear. ECGS is cleared
when the external clock generator is turned off or in stop mode (ECGEN is clear) or when EOFF is set.
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OUTPUT CLOCK
DLF MEASURE
ESTBCLK
ECGEN
IBASE
CMON
CMON
ICGEN
FICGS
ECLK
EREF
IREF
NAME
NAME
NAME
NAME
MC68HC908EY16A • MC68HC908EY8A Data Sheet, Rev. 1
Figure 8-7. External Clock Activity Detector
Figure 8-6. Internal Clock Activity Detector
D
CK
D
CK
DFFRS
DFFRS
CONFIGURATION REGISTER BIT
TOP LEVEL SIGNAL
CONFIGURATION REGISTER BIT
TOP LEVEL SIGNAL
R
S
R
S
Q
Q
CK
CK
1/4
1/4
R
R
Q
Q
D
CK
D
CK
DFFRR
DFFRR
R
R
R
R
Q
Q
D
CK
DFFRR
NAME
NAME
NAME
NAME
R
R
Q
MODULE SIGNAL
MODULE SIGNAL
REGISTER BIT
REGISTER BIT
EGGS
EOFF
ICGS
IOFF
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