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<title>I/O Port</title>
<articleinfo>

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

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</authorgroup>

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

<keywordset>
<keyword>KDE</keyword>
<keyword>KControl</keyword>
<keyword>ioports</keyword>
<keyword>system information</keyword>
</keywordset>
</articleinfo>

<sect1>
<title>Input/Output Port Information</title>

<para>This page displays information about the I/O ports.</para>

<para>I/O Ports are memory addresses used by the processor for direct
communication with a device that has sent an
interrupt signal to the processor.</para>

<para>The exchange of commands or data between the processor and the device
takes place through the I/O port address of the device, which is a
 hexadecimal
number.  No two devices can share the same I/O port.  Many devices use
 multiple
I/O port addresses, which are expressed as a range of hexadecimal
numbers. </para>

<note><para>The exact information displayed is system-dependent. On some
systems, I/O port information can not yet be displayed.</para></note>

<para>On &Linux;, this information is read from <filename
class="devicefile">/proc/ioports</filename> which is only available if
the <filename class="devicefile">/proc</filename> pseudo-filesystem is
compiled into the kernel.  A list of all currently-registered I/O port
regions that are in use is shown.</para>

<para>The first column is the I/O port (or the range of I/O ports), the
second column identifies the device that uses these I/O ports.</para>

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

</sect1>
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