
MC68HC908GZ60 MC68HC908GZ48 MC68HC908GZ32 Data Sheet, Rev. 6
Freescale Semiconductor
95
Chapter 6
Computer Operating Properly (COP) Module
6.1 Introduction
The computer operating properly (COP) module contains a free-running counter that generates a reset if
allowed to overflow. The COP module helps software recover from runaway code. Prevent a COP reset
by clearing the COP counter periodically. The COP module can be disabled through the COPD bit in the
CONFIG register.
6.2 Functional Description
Figure 6-1. COP Block Diagram
COPCTL WRITE
CGMXCLK
RESET CIRCUIT
RESET STATUS REGISTER
INTERNAL RESET SOURCES
12-BIT SIM COUNTER
CL
EAR
ALL
STAGES
6-BIT COP COUNTER
COP DISABLE
RESET
COPCTL WRITE
CLEAR
COP MODULE
COPEN (FROM SIM)
COP COUNTER
COP CLOCK
COP
T
IMEOUT
STOP INSTRUCTION
(FROM CONFIG)
COP RATE SEL
(FROM CONFIG)
CLEAR
STA
G
ES
5
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