mc68hc908gr8a Freescale Semiconductor, Inc, mc68hc908gr8a Datasheet - Page 79

• Manufacturer Part Number: mc68hc908gr8a
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

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
Freescale Semiconductor
1. See
INTERNAL RESET SOURCES
shows the structure of the COP module.
(COPRS FROM CONFIG1)
COPD (FROM CONFIG1)
Chapter 14 System Integration Module (SIM)
STOP INSTRUCTION
COPEN (FROM SIM)
COP RATE SELECT
COPCTL WRITE
COPCTL WRITE
CGMXCLK
RESET
MC68HC908GR8A • MC68HC908GR4A Data Sheet, Rev. 5
(1)
Figure 6-1. COP Block Diagram
COP CLOCK
12-BIT SIM COUNTER
COP COUNTER
CLEAR
6-BIT COP COUNTER
COP MODULE
SIM MODULE
for more details.
RESET STATUS REGISTER
SIM RESET CIRCUIT
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