mc68hc908gp32 Freescale Semiconductor, Inc, mc68hc908gp32 Datasheet - Page 85

• Manufacturer Part Number: mc68hc908gp32
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Chapter 7
Computer Operating Properly (COP)
7.1 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.
7.2 Functional Description
Figure 7-1
Freescale Semiconductor
INTERNAL RESET SOURCES
RESET VECTOR FETCH
shows the structure of the COP module.
STOP INSTRUCTION
COPEN (FROM SIM)
(FROM CONFIG)
COP RATE SEL
(FROM CONFIG)
COPCTL WRITE
COPCTL WRITE
COP DISABLE
CGMXCLK
RESET
COP MODULE
COP CLOCK
12-BIT COP PRESCALER
Figure 7-1. COP Block Diagram
MC68HC908GP32 Data Sheet, Rev. 10
COP COUNTER
6-BIT COP COUNTER
CLEAR
RESET STATUS REGISTER
RESET CIRCUIT
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