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<?xml version="1.0" ?>
<!DOCTYPE article PUBLIC "-//KDE//DTD DocBook XML V4.2-Based Variant V1.1//EN"
"dtd/kdex.dtd" [
<!ENTITY % addindex "IGNORE">
<!ENTITY % English "INCLUDE" > <!-- change language only here -->
]>

<article lang="&language;">
<title>Interrupt Request (<abbrev>IRQ</abbrev>) Lines</title>
<articleinfo>

<authorgroup>
<author>&Matthias.Hoelzer-Kluepfel;</author>
<author>&Helge.Deller;</author>
<author>&Duncan.Haldane;</author>
<author>&Mike.McBride;</author>
<!-- TRANS:ROLES_OF_TRANSLATORS -->
</authorgroup>

<date>2002-02-12</date>
<releaseinfo>3.00.00</releaseinfo>

<keywordset>
<keyword>KDE</keyword>
<keyword>KControl</keyword>
<keyword>IRQ</keyword>
<keyword>interrupts</keyword>
<keyword>system information</keyword>
</keywordset>
</articleinfo>

<sect1>
<title>Interrupt Request (<abbrev>IRQ</abbrev>) Lines in Use</title>

<para>This page displays information about the Interrupt Request
Lines in use, and the devices that use them.</para>

<para>An <acronym>IRQ</acronym> is a hardware line used in a
<acronym>PC</acronym> by (<acronym>ISA</acronym> bus) devices like
keyboards, modems, sound cards, &etc;, to send interrupt signals to the
processor to tell it that the device is ready to send or accept data.
Unfortunately, there are  only sixteen <acronym>IRQ</acronym>'s (0-15)
available in the i386 (<acronym>PC</acronym>) architecture for sharing among
the various <acronym>ISA</acronym> devices.</para>

<para>Many hardware problems are the result of <acronym>IRQ</acronym>
conflicts, when two devices try to use the same <acronym>IRQ</acronym>, or
software is misconfigured to use a different <acronym>IRQ</acronym> from the
one a device is actually configured for.</para>

<note><para>The exact information displayed is system-dependent.  On some
systems, <acronym>IRQ</acronym> information cannot be displayed
 yet.</para></note>

<para>On &Linux;, this information is read from
<filename class="directory">/proc/interrupts</filename>, which is only
available if the <filename class="directory">/proc</filename>
pseudo-filesystem is compiled into the  kernel.</para>

<para>The first column, is the <acronym>IRQ</acronym> number.  The second
column, is the number of interrupts that have been received since the last
reboot.  The third column shows the type of interrupt.  The fourth,
identifies the device assigned to that interrupt.</para>

<para>The user cannot modify any settings on this page.</para>

</sect1>

</article>