s908gz60cfa Freescale Semiconductor, Inc, s908gz60cfa Datasheet - Page 95

• Manufacturer Part Number: s908gz60cfa
• Description: M68hc08 Microcontrollers
• 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
INTERNAL RESET SOURCES
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
MC68HC908GZ60 • MC68HC908GZ48 • MC68HC908GZ32 Data Sheet, Rev. 6
RESET
COP MODULE
COP CLOCK
Figure 6-1. COP Block Diagram
12-BIT SIM COUNTER
COP COUNTER
6-BIT COP COUNTER
CLEAR
RESET STATUS REGISTER
RESET CIRCUIT
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