Motorola MC68HC05RC16, MC68HC05RC8 Section 4. Interrupts

General Release Specification — MC68HC05RC16

Section 4. Interrupts

4.1 Contents

4.2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

4.3 CPU Interrupt Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38

4.4 Reset Interrupt Sequence. . . . . . . . . . . . . . . . . . . . . . . . . . . . .39

4.5 Software Interrupt (SWI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39

4.6 Hardware Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41

4.7 External Interrupt (IRQ/Port B Keyscan). . . . . . . . . . . . . . . . . .41

4.8 External Interrupt Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

4.9 Carrier Modulator Transmitter Interrupt (CMT) . . . . . . . . . . . . .42

4.10 Core Timer Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43

4.2 Introduction

The MCU can be interrupted four different ways:

1.Nonmaskable software interrupt instruction (SWI)

2.External asynchronous interrupt (IRQ/port B keyscan)

3.Internal carrier modulator transmitter interrupt

4.Internal core timer interrupt

MC68HC05RC16 — Rev. 3.0		General Release Specification
MOTOROLA	Interrupts	37