IRQ Module Block Diagram | Freescale Semiconductor MC68HC908MR16

Chapter 8 External Interrupt (IRQ)

8.1 Introduction

This section describes the external interrupt (IRQ) module, which supports external interrupt functions.

8.2 Features

Features of the IRQ module include:

•A dedicated external interrupt pin, IRQ

•Hysteresis buffers

8.3 Functional Description

A logic 0 applied to any of the external interrupt pins can latch a CPU interrupt request. Figure 8-1shows the structure of the IRQ module.

IRQ

VDD	ACK1
VDD
D	CLR Q	SYNCHRO-
		SYNCHRO-
CK		NIZER
CK
	IRQ
	LATCH
		IMASK1
MODE1
		HIGH
		VOLTAGE
		DETECT

IRQ

INTERRUPT

REQUEST

TO MODE SELECT

LOGIC

Figure 8-1. IRQ Module Block Diagram

Addr.	Register Name
	IRQ Status/Control Register	Read:
	IRQ Status/Control Register
$003F	(ISCR)	Write:
	See page 94.	Reset:
		Reset:

Bit 7	6	5	4	3	2	1	Bit 0
0	0	0	0	IRQF	0	IMASK1	MODE1

R	R	R	R		ACK1
R	R	R	R		ACK1

0	0	0	0	0	0	0	0

R	= Reserved

Figure 8-2. IRQ I/O Register Summary

MC68HC908MR32 • MC68HC908MR16 Data Sheet, Rev. 6.1

Freescale Semiconductor

MC68HC908MR16, MC68HC908MR32 specifications

Freescale Semiconductor's MC68HC908MR32 and MC68HC908MR16 microcontrollers are part of the popular HC08 family, designed primarily for embedded applications. These microcontrollers are particularly favored in automotive, industrial, and consumer product sectors due to their reliability and versatility.

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The MC68HC908MR32 variant is equipped with 32KB of flash memory, which allows for the storage of complex programs and extensive data handling. In contrast, the MC68HC908MR16 features 16KB of flash memory, making it ideal for simpler applications. Both microcontrollers also come with 1KB of RAM, enabling efficient data processing and real-time operations.

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Security is another crucial aspect of these microcontrollers. They have built-in fail-safe mechanisms to ensure reliable operation under various conditions, making them suitable for critical systems. Additionally, their robust architecture helps to safeguard against potential disruptions or attacks.

In summary, Freescale Semiconductor's MC68HC908MR32 and MC68HC908MR16 microcontrollers are key players in the embedded systems landscape. Their blend of power efficiency, integrated features, and scalability ensures they remain relevant for a wide array of applications, making them a favored choice among engineers and developers looking for dependable solutions in a competitive market.

Freescale Semiconductor MC68HC908MR16 Chapter External Interrupt IRQ, IRQ Module Block Diagram

Models: MC68HC908MR16 MC68HC908MR32

Chapter 8

External Interrupt (IRQ)