General Release Specification — MC68HC05RC16

Section 5. Resets

5.1 Contents

5.2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45

5.3 External Reset (RESET). . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46

5.4 Low-Power External Reset (LPRST) . . . . . . . . . . . . . . . . . . . .48

5.5 Internal Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48

5.5.1 Power-On Reset (POR). . . . . . . . . . . . . . . . . . . . . . . . . . . .48

5.5.2 Computer Operating Properly Reset (COPR) . . . . . . . . . . .49

5.5.2.1 Resetting the COP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49

5.5.2.2 COP During Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . .49

5.5.2.3 COP During Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . .49

5.5.2.4 COP Watchdog Timer Considerations . . . . . . . . . . . . . . .50

5.5.2.5 COP Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51

5.5.3 Illegal Address. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51

5.2 Introduction

The MCU can be reset from five sources: two external inputs and three

internal restart conditions. The RESET and LPRST pins are inputs as shown in Figure 5-1. All the internal peripheral modules will be reset by

the internal reset signal (RST). Refer to Figure 5-2for reset timing detail.

MC68HC05RC16 — Rev. 3.0

 

General Release Specification

 

 

 

MOTOROLA

Resets

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