MC68HC908MR16/MC68HC908MR32 — Rev. 4.0 Advance Information
MOTOROLA Computer Operating Properly (COP) 323
Advance Information — MC68HC908MR16/MC68HC908MR32
Section 16. Computer Operating Properly (COP)

16.1 Contents

16.2 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .323
16.3 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .324
16.4 I/O Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .325
16.4.1 CGMXCLK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .325
16.4.2 COPCTL Write . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .325
16.4.3 Power-On Reset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .325
16.4.4 Internal Reset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .326
16.4.5 Reset Vector Fetch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .326
16.4.6 COPD (COP Disable). . . . . . . . . . . . . . . . . . . . . . . . . . . . .326
16.5 COP Control Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .326
16.6 Interrupts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .326
16.7 Monitor Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .327
16.8 Wait Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .327
16.9 Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .327

16.2 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 sof tware recover from
runaway code. Prevent a COP reset by periodically clearing the COP
counter.