MC908AZ60ACFUER Datasheet, PDF (164/414 Pages) Freescale Semiconductor, Inc – To provide the most up-to-date information, the revision of our documents on the World Wide Web will be the most current. Your printed copy may be an earlier revision. To verify you have the latest information available, refer to:

Computer Operating Properly (COP)
CGMXCLK
12-BIT COP PRESCALER
STOP INSTRUCTION
INTERNAL RESET SOURCES
RESET VECTOR FETCH
COPCTL WRITE
COPD FROM CONFIG-1
RESET
COPCTL WRITE
COPL FROM CONFIG-1
6-BIT COP COUNTER
CLEAR COP
COUNTER
RESET
RESET STATUS
REGISTER
Figure 15-1. COP Block Diagram
15.3.1 CGMXCLK
CGMXCLK is the crystal oscillator output signal. CGMXCLK frequency is equal to the crystal frequency.
15.3.2 STOP Instruction
The STOP instruction clears the COP prescaler.
15.3.3 COPCTL Write
Writing any value to the COP control register (COPCTL) (see 15.4 COP Control Register), clears the COP
counter and clears stages 12 through 4 of the COP prescaler. Reading the COP control register returns
the reset vector.
15.3.4 Power-On Reset
The power-on reset (POR) circuit clears the COP prescaler 4096 CGMXCLK cycles after power-up.
15.3.5 Internal Reset
An internal reset clears the COP prescaler and the COP counter.
MC68HC908AZ60A • MC68HC908AS60A • MC68HC908AS60E Data Sheet, Rev. 6
164
Freescale Semiconductor