MC68HC908QL4 Data Sheet, Rev. 8
Freescale Semiconductor
67
Chapter 6
Computer Operating Properly (COP)
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
configuration 1 (CONFIG1) register.
6.2 Functional Description
Figure 6-1. COP Block Diagram
COPCTL WRITE
BUSCLKX4
STOP INSTRUCTION
SIM RESET CIRCUIT
RESET STATUS REGISTER
INTERNAL RESET SOURCES(1)
SIM MODULE
CLE
AR
STAG
ES
5–12
12-BIT SIM COUNTER
CLEA
RALL
STAG
ES
COPD (FROM CONFIG1)
RESET
COPCTL WRITE
CLEAR
COP MODULE
COPEN (FROM SIM)
COP CLOCK
CO
PT
IM
EOU
T
COP RATE SELECT
(COPRS FROM CONFIG1)
6-BIT COP COUNTER
COP COUNTER