s908gr32ag3vfa Freescale Semiconductor, Inc, s908gr32ag3vfa Datasheet - Page 93

• Manufacturer Part Number: s908gr32ag3vfa
• 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
MC68HC908GR60A • MC68HC908GR48A • MC68HC908GR32A Data Sheet, Rev. 5
COP DISABLE
CGMXCLK
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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