MC908MR32CFUE Datasheet, PDF (75/282 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 6
Computer Operating Properly (COP)
6.1 Introduction
This section describes the computer operating properly module, a free-running counter that generates a
reset if allowed to overflow. The computer operating properly (COP) module helps software recover from
runaway code. Prevent a COP reset by periodically clearing the COP counter.
6.2 Functional Description
Figure 6-1 shows the structure of the COP module. A summary of the input/output (I/O) register is shown
in Figure 6-2.
CGMXCLK
SIM
13-BIT SIM COUNTER
SIM RESET CIRCUIT
SIM RESET STATUS REGISTER
INTERNAL RESET SOURCES(1)
RESET VECTOR FETCH
COPCTL WRITE
COPD (FROM CONFIG)
RESET
COPCTL WRITE
COP MODULE
6-BIT COP COUNTER
CLEAR
COP COUNTER
Note 1. See 14.3.2 Active Resets from Internal Sources.
Figure 6-1. COP Block Diagram
MC68HC908MR32 • MC68HC908MR16 Data Sheet, Rev. 6.1
Freescale Semiconductor
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