MC68HC08GP32A Datasheet, PDF (83/258 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 7
External Interrupt (IRQ)
7.1 Introduction
The IRQ (external interrupt) module provides a maskable interrupt input.
7.2 Features
Features of the IRQ module include:
• A dedicated external interrupt pin (IRQ)
• IRQ interrupt control bits
• Hysteresis buffer
• Programmable edge-only or edge and level interrupt sensitivity
• Automatic interrupt acknowledge
• Internal pullup resistor
7.3 Functional Description
A low level applied to the external interrupt pin can latch a CPU interrupt request. Figure 7-1 shows the
structure of the IRQ module.
RESET
ACK
VECTOR
FETCH
DECODER
V_DD
INTERNAL
PULLUP
DEVICE
IRQ
V_DD
CLR
D
Q
CK
SYNCHRONIZER
TO CPU FOR
BIL/BIH
INSTRUCTIONS
IRQF
IRQ
INTERRUPT
REQUEST
IMASK
MODE
HIGH
VOLTAGE
DETECT
Figure 7-1. IRQ Module Block Diagram
Freescale Semiconductor
MC68HC08GP32A • MC68HC08GP16A Data Sheet, Rev. 1.0
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