DOCUMENT:Q37928  10-NOV-1999  [macmail]
TITLE   :Mac DOS: Hardware Interrupts Used by Common Devices
PRODUCT :Microsoft Mail For Appletalk Networks
PROD/VER::3.0,3.1
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Mail for AppleTalk Networks, MS-DOS workstation, versions 3.0, 3.1 
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SYMPTOMS
========

Interrupts are the means by which the computer's circuitry outside the central
processor reports that something (such as a keystroke) has occurred and requests
that some action be taken. Serious problems may occur if two devices installed
in a computer are using the same interrupt; for example, one of the devices may
be disabled, or your computer system may stop responding (hang) because the
computer cannot service two interrupts at one time. This problem may occur when
you try to install an AppleTalk network card for use with Microsoft Mail (MS-DOS
client).

RESOLUTION
==========

To resolve an interrupt conflict, set one of the devices to use another
interrupt (if possible), or remove one of the devices from your hardware
configuration.

MORE INFORMATION
================

The following is a table of hardware interrupts used by the IBM PC/XT or PC/AT
and common devices:

   Interrupt    Potential Use
   ---------    -------------

    0           System board timer

    1           Keyboard

    2           PC/AT hard disk*, bus mouse, some clock calendars, UBNET
                cards (on PC/XTs), Apple LocalTalk, or TOPS FlashCard
                network cards

    3           Serial port 2, bus mouse, Apple LocalTalk, TOPS FlashCard,
                or MacBridge ATB network cards

    4           Serial port 1, bus mouse, Apple LocalTalk network card

    5           PC/XT hard disk, bus mouse, UBNET card (on PC/ATs)

    6           Floppy disk controller

    7           Parallel port 1

IBM PC/AT Only
--------------

    8           Real-time clock

    9           Software redirect to IRQ2

   10-12        Reserved

   13           Coprocessor

   14           Hard disk controller

   15           Reserved

* The IBM PC/AT uses IRQ2 to access interrupts 8-15 by activating a separate
interrupt controller.


Additional query words: 3.00 3.10 lock

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Keywords          :  
Technology        : kbZNotKeyword2 kbMailSearch kbZNotKeyword3 kbMailATN300DOS kbMailATN310DOS
Version           : :3.0,3.1

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