mc68hc908qz16 Freescale Semiconductor, Inc, mc68hc908qz16 Datasheet - Page 83

• Manufacturer Part Number: mc68hc908qz16
• 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
shows the structure of the COP module.
SIM MODULE
SIM RESET CIRCUIT
BUSCLKX4
12-BIT SIM COUNTER
RESET STATUS REGISTER
(1)
INTERNAL RESET SOURCES
RESET VECTOR FETCH
COPCTL WRITE
COP CLOCK
COP MODULE
6-BIT COP COUNTER
COPEN (FROM SIM)
COPD (FROM CONFIG1)
CLEAR
RESET
COP COUNTER
COPCTL WRITE
COP RATE SELECT
(COPRS FROM CONFIG1)
1. See
Chapter 16 System Integration Module (SIM)
for more details.
Figure 6-1. COP Block Diagram
MC68HC908GZ16 • MC68HC908GZ8 Data Sheet, Rev. 4
Freescale Semiconductor
83