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Date:      Tue, 6 May 2014 20:34:49 +0000 (UTC)
From:      Dru Lavigne <dru@FreeBSD.org>
To:        doc-committers@freebsd.org, svn-doc-all@freebsd.org, svn-doc-head@freebsd.org
Subject:   svn commit: r44781 - head/en_US.ISO8859-1/books/handbook/serialcomms
Message-ID:  <201405062034.s46KYnwS018742@svn.freebsd.org>

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Author: dru
Date: Tue May  6 20:34:49 2014
New Revision: 44781
URL: http://svnweb.freebsd.org/changeset/doc/44781

Log:
  White space fix only. Translators can ignore.
  
  Sponsored by:	iXsystems

Modified:
  head/en_US.ISO8859-1/books/handbook/serialcomms/chapter.xml

Modified: head/en_US.ISO8859-1/books/handbook/serialcomms/chapter.xml
==============================================================================
--- head/en_US.ISO8859-1/books/handbook/serialcomms/chapter.xml	Tue May  6 19:47:57 2014	(r44780)
+++ head/en_US.ISO8859-1/books/handbook/serialcomms/chapter.xml	Tue May  6 20:34:49 2014	(r44781)
@@ -63,441 +63,435 @@
     <variablelist>
       <varlistentry>
 	<term><acronym>bps</acronym></term>
-	  <listitem>
-	    <para>Bits per
-	      Second<indexterm><primary>bits-per-second</primary></indexterm>
-	      (<acronym>bps</acronym>) is the rate at which data is
-	      transmitted.</para>
-	  </listitem>
-	</varlistentry>
+	<listitem>
+	  <para>Bits per
+	    Second<indexterm><primary>bits-per-second</primary></indexterm>
+	    (<acronym>bps</acronym>) is the rate at which data is
+	    transmitted.</para>
+	</listitem>
+      </varlistentry>
 
-	<varlistentry>
-	  <term><acronym>DTE</acronym></term>
-	  <listitem>
-	    <para>Data Terminal
-	      Equipment<indexterm><primary>DTE</primary></indexterm>
-	      (<acronym>DTE</acronym>) is one of two endpoints in a
-	      serial communication.  An example would be a
-	      computer.</para>
-	  </listitem>
-	</varlistentry>
+      <varlistentry>
+	<term><acronym>DTE</acronym></term>
+	<listitem>
+	  <para>Data Terminal
+	    Equipment<indexterm><primary>DTE</primary></indexterm>
+	    (<acronym>DTE</acronym>) is one of two endpoints in a
+	    serial communication.  An example would be a
+	    computer.</para>
+	</listitem>
+      </varlistentry>
 
-	<varlistentry>
-	  <term><acronym>DCE</acronym></term>
-	  <listitem>
-	    <para>Data Communications
-	      Equipment<indexterm><primary>DCE</primary></indexterm>
-	      (<acronym>DTE</acronym>) is the other endpoint in a
-	      serial communication.  Typically, it is a modem.</para>
-	  </listitem>
-	</varlistentry>
+      <varlistentry>
+	<term><acronym>DCE</acronym></term>
+	<listitem>
+	  <para>Data Communications
+	    Equipment<indexterm><primary>DCE</primary></indexterm>
+	    (<acronym>DTE</acronym>) is the other endpoint in a
+	    serial communication.  Typically, it is a modem.</para>
+	</listitem>
+      </varlistentry>
 
-	<varlistentry>
-	  <term>RS-232</term>
+      <varlistentry>
+	<term>RS-232</term>
+	<listitem>
+	  <para>The original standard which defined hardware serial
+	    communications.  It has since been renamed to
+	    <acronym>TIA</acronym>-232<indexterm><primary>RS-232C
+	      cables</primary></indexterm>.</para>
+	</listitem>
+      </varlistentry>
+    </variablelist>
 
-	  <listitem>
-	    <para>The original standard which defined hardware serial
-	      communications.  It has since been renamed to
-	      <acronym>TIA</acronym>-232<indexterm><primary>RS-232C
-		cables</primary></indexterm>.</para>
-	  </listitem>
-	</varlistentry>
-      </variablelist>
+    <para>When talking about communications data rates, this section
+      does not use the term <quote>baud</quote>.  Baud refers to the
+      number of electrical state transitions that may be made in a
+      period of time, while <acronym>bps</acronym> is the
+      <emphasis>correct</emphasis> term to use.</para>
+
+    <para>To connect a modem or serial terminal to a &os; system, a
+      serial port on the computer and the proper cable to connect to
+      the serial device are needed.  Users who are already familiar
+      with serial hardware and cabling can safely skip this
+      section.</para>
+
+    <sect2 xml:id="term-cables-null">
+      <title>Serial Cables and Ports</title>
+
+      <para>There are several different kinds of serial cables.  The
+	two most common types are null-modem cables and standard
+	RS-232 cables.  The documentation for the hardware should
+	describe the type of cable required.</para>
 
-      <para>When talking about communications data rates, this section
-	does not use the term <quote>baud</quote>.  Baud refers to the
-	number of electrical state transitions that may be made in a
-	period of time, while <acronym>bps</acronym> is the
-	<emphasis>correct</emphasis> term to use.</para>
-
-      <para>To connect a modem or serial terminal to a &os; system, a
-	serial port on the computer and the proper cable to connect to
-	the serial device are needed.  Users who are already familiar
-	with serial hardware and cabling can safely skip this
-	section.</para>
-
-      <sect2 xml:id="term-cables-null">
-	<title>Serial Cables and Ports</title>
-
-	<para>There are several different kinds of serial cables.  The
-	  two most common types are null-modem cables and standard
-	  RS-232 cables.  The documentation for the hardware should
-	  describe the type of cable required.</para>
+      <indexterm>
+	<primary>null-modem cable</primary>
+      </indexterm>
 
-	<indexterm>
-	  <primary>null-modem cable</primary>
-	</indexterm>
+      <para>A null-modem cable passes some signals, such as
+	<quote>Signal Ground</quote>, straight through, but switches
+	other signals.  For example, the <quote>Transmitted
+	  Data</quote> pin on one end goes to the <quote>Received
+	  Data</quote> pin on the other end.</para>
+
+      <para>A null-modem cable can be constructed for use with
+	terminals.  The following table shows the RS-232C <link
+	  linkend="serialcomms-signal-names">signal names</link> and
+	the pin numbers on a DB-25 connector.  While the standard
+	calls for a straight-through pin 1 to pin 1
+	<emphasis>Protective Ground</emphasis> line, it is often
+	omitted.  Some terminals work using only pins 2, 3, and 7,
+	while others require different configurations than the
+	examples shown below.</para>
 
-	<para>A null-modem cable passes some signals, such as
-	  <quote>Signal Ground</quote>, straight through, but
-	  switches other signals.  For example, the
-	  <quote>Transmitted Data</quote> pin on one end goes to the
-	  <quote>Received Data</quote> pin on the other end.</para>
-
-	<para>A null-modem cable can be constructed for use with
-	  terminals.  The following table shows the RS-232C <link linkend="serialcomms-signal-names">signal names</link>
-	  and the pin numbers on a DB-25 connector.  While the
-	  standard calls for a straight-through pin 1 to pin 1
-	  <emphasis>Protective Ground</emphasis> line, it is often
-	  omitted.  Some terminals work using only pins 2, 3, and
-	  7, while others require different configurations than
-	  the examples shown below.</para>
-
-	<table frame="none" pgwide="1">
-	  <title>DB-25 to DB-25 Null-Modem Cable</title>
-
-	  <tgroup cols="5">
-	    <thead>
-	      <row>
-		<entry align="left">Signal</entry>
-		<entry align="left">Pin #</entry>
-		<entry/>
-		<entry align="left">Pin #</entry>
-		<entry align="left">Signal</entry>
-	      </row>
-	    </thead>
-
-	    <tbody>
-	      <row>
-		<entry>SG</entry>
-		<entry>7</entry>
-		<entry>connects to</entry>
-		<entry>7</entry>
-		<entry>SG</entry>
-	      </row>
-
-	      <row>
-		<entry>TD</entry>
-		<entry>2</entry>
-		<entry>connects to</entry>
-		<entry>3</entry>
-		<entry>RD</entry>
-	      </row>
-
-	      <row>
-		<entry>RD</entry>
-		<entry>3</entry>
-		<entry>connects to</entry>
-		<entry>2</entry>
-		<entry>TD</entry>
-	      </row>
-
-	      <row>
-		<entry>RTS</entry>
-		<entry>4</entry>
-		<entry>connects to</entry>
-		<entry>5</entry>
-		<entry>CTS</entry>
-	      </row>
-
-	      <row>
-		<entry>CTS</entry>
-		<entry>5</entry>
-		<entry>connects to</entry>
-		<entry>4</entry>
-		<entry>RTS</entry>
-	      </row>
-
-	      <row>
-		<entry>DTR</entry>
-		<entry>20</entry>
-		<entry>connects to</entry>
-		<entry>6</entry>
-		<entry>DSR</entry>
-	      </row>
-
-	      <row>
-		<entry>DTR</entry>
-		<entry>20</entry>
-		<entry>connects to</entry>
-		<entry>8</entry>
-		<entry>DCD</entry>
-	      </row>
-
-	      <row>
-		<entry>DSR</entry>
-		<entry>6</entry>
-		<entry>connects to</entry>
-		<entry>20</entry>
-		<entry>DTR</entry>
-	      </row>
-
-	      <row>
-		<entry>DCD</entry>
-		<entry>8</entry>
-		<entry>connects to</entry>
-		<entry>20</entry>
-		<entry>DTR</entry>
-	      </row>
-	    </tbody>
-	  </tgroup>
-	</table>
-
-	<para>The next two tables show two other common
-	  schemes.</para>
-
-	<table frame="none" pgwide="1">
-	  <title>DB-9 to DB-9 Null-Modem Cable</title>
-
-	  <tgroup cols="5">
-	    <thead>
-	      <row>
-		<entry align="left">Signal</entry>
-		<entry align="left">Pin #</entry>
-		<entry/>
-		<entry align="left">Pin #</entry>
-		<entry align="left">Signal</entry>
-	      </row>
-	    </thead>
-
-	    <tbody>
-	      <row>
-		<entry>RD</entry>
-		<entry>2</entry>
-		<entry>connects to</entry>
-		<entry>3</entry>
-		<entry>TD</entry>
-	      </row>
-
-	      <row>
-		<entry>TD</entry>
-		<entry>3</entry>
-		<entry>connects to</entry>
-		<entry>2</entry>
-		<entry>RD</entry>
-	      </row>
-
-	      <row>
-		<entry>DTR</entry>
-		<entry>4</entry>
-		<entry>connects to</entry>
-		<entry>6</entry>
-		<entry>DSR</entry>
-	      </row>
-
-	      <row>
-		<entry>DTR</entry>
-		<entry>4</entry>
-		<entry>connects to</entry>
-		<entry>1</entry>
-		<entry>DCD</entry>
-	      </row>
-
-	      <row>
-		<entry>SG</entry>
-		<entry>5</entry>
-		<entry>connects to</entry>
-		<entry>5</entry>
-		<entry>SG</entry>
-	      </row>
-
-	      <row>
-		<entry>DSR</entry>
-		<entry>6</entry>
-		<entry>connects to</entry>
-		<entry>4</entry>
-		<entry>DTR</entry>
-	      </row>
-
-	      <row>
-		<entry>DCD</entry>
-		<entry>1</entry>
-		<entry>connects to</entry>
-		<entry>4</entry>
-		<entry>DTR</entry>
-	      </row>
-
-	      <row>
-		<entry>RTS</entry>
-		<entry>7</entry>
-		<entry>connects to</entry>
-		<entry>8</entry>
-		<entry>CTS</entry>
-	      </row>
-
-	      <row>
-		<entry>CTS</entry>
-		<entry>8</entry>
-		<entry>connects to</entry>
-		<entry>7</entry>
-		<entry>RTS</entry>
-	      </row>
-	    </tbody>
-	  </tgroup>
-	</table>
-
-	<table frame="none" pgwide="1">
-	  <title>DB-9 to DB-25 Null-Modem Cable</title>
-
-	  <tgroup cols="5">
-	    <thead>
-	      <row>
-		<entry align="left">Signal</entry>
-		<entry align="left">Pin #</entry>
-		<entry/>
-		<entry align="left">Pin #</entry>
-		<entry align="left">Signal</entry>
-	      </row>
-	    </thead>
-
-	    <tbody>
-	      <row>
-		<entry>RD</entry>
-		<entry>2</entry>
-		<entry>connects to</entry>
-		<entry>2</entry>
-		<entry>TD</entry>
-	      </row>
-
-	      <row>
-		<entry>TD</entry>
-		<entry>3</entry>
-		<entry>connects to</entry>
-		<entry>3</entry>
-		<entry>RD</entry>
-	      </row>
-
-	      <row>
-		<entry>DTR</entry>
-		<entry>4</entry>
-		<entry>connects to</entry>
-		<entry>6</entry>
-		<entry>DSR</entry>
-	      </row>
-
-	      <row>
-		<entry>DTR</entry>
-		<entry>4</entry>
-		<entry>connects to</entry>
-		<entry>8</entry>
-		<entry>DCD</entry>
-	      </row>
-
-	      <row>
-		<entry>SG</entry>
-		<entry>5</entry>
-		<entry>connects to</entry>
-		<entry>7</entry>
-		<entry>SG</entry>
-	      </row>
-
-	      <row>
-		<entry>DSR</entry>
-		<entry>6</entry>
-		<entry>connects to</entry>
-		<entry>20</entry>
-		<entry>DTR</entry>
-	      </row>
-
-	      <row>
-		<entry>DCD</entry>
-		<entry>1</entry>
-		<entry>connects to</entry>
-		<entry>20</entry>
-		<entry>DTR</entry>
-	      </row>
-
-	      <row>
-		<entry>RTS</entry>
-		<entry>7</entry>
-		<entry>connects to</entry>
-		<entry>5</entry>
-		<entry>CTS</entry>
-	      </row>
-
-	      <row>
-		<entry>CTS</entry>
-		<entry>8</entry>
-		<entry>connects to</entry>
-		<entry>4</entry>
-		<entry>RTS</entry>
-	      </row>
-	    </tbody>
-	  </tgroup>
-	</table>
+      <table frame="none" pgwide="1">
+	<title>DB-25 to DB-25 Null-Modem Cable</title>
 
-	<note>
-	  <para>When one pin at one end connects to a pair of pins
-	    at the other end, it is usually implemented with one
-	    short wire between the pair of pins in their connector
-	    and a long wire to the other single pin.</para>
-	</note>
+	<tgroup cols="5">
+	  <thead>
+	    <row>
+	      <entry align="left">Signal</entry>
+	      <entry align="left">Pin #</entry>
+	      <entry/>
+	      <entry align="left">Pin #</entry>
+	      <entry align="left">Signal</entry>
+	    </row>
+	  </thead>
 
-	<para>The above designs seem to be the most popular.  In
-	  another variation, SG connects to SG, TD connects to RD,
-	  RTS and CTS connect to DCD, DTR connects to DSR, and
-	  vice-versa.</para>
-
-	<indexterm><primary>RS-232C cables</primary></indexterm>
-
-	<para>A standard serial cable passes all of the RS-232C
-	  signals straight through.  The <quote>Transmitted
-	    Data</quote> pin on one end of the cable goes to the
-	  <quote>Transmitted Data</quote> pin on the other end.
-	  This is the type of cable used to connect a modem to
-	  the &os; system, and is also appropriate for some
-	  terminals.</para>
-
-	<para>Serial ports are the devices through which data is
-	  transferred between the &os; host computer and the
-	  terminal.  This section describes the kinds of ports that
-	  exist and how they are addressed in &os;.</para>
-
-	<para>Several kinds of serial ports exist.  Before
-	  purchasing or constructing a cable, make sure it will
-	  fit the ports on the terminal and on the &os;
-	  system.</para>
-
-	<para>Most terminals have DB-25 ports.  Personal computers
-	  may have DB-25 or DB-9 ports.  A multiport serial card may
-	  have RJ-12 or RJ-45 ports.</para>
-
-	<para>See the documentation that accompanied the hardware
-	  for specifications on the kind of port or visually verify
-	  the type of port.</para>
-
-	<para>In &os;, each serial port is accessed through an
-	  entry in <filename>/dev</filename>.
-	  There are two different kinds of entries:</para>
+	  <tbody>
+	    <row>
+	      <entry>SG</entry>
+	      <entry>7</entry>
+	      <entry>connects to</entry>
+	      <entry>7</entry>
+	      <entry>SG</entry>
+	    </row>
 
-	<itemizedlist>
-	  <listitem>
-	    <para>Call-in ports are named
-	      <filename>/dev/ttyu<replaceable>N</replaceable></filename>
-	      where <replaceable>N</replaceable> is the port number,
-	      starting from zero.  Generally, the call-in port is
-	      used for terminals.  Call-in ports require that the
-	      serial line assert the Data Carrier Detect
-	      (<acronym>DCD</acronym>) signal to work
-	      correctly.</para>
-	  </listitem>
+	    <row>
+	      <entry>TD</entry>
+	      <entry>2</entry>
+	      <entry>connects to</entry>
+	      <entry>3</entry>
+	      <entry>RD</entry>
+	    </row>
 
-	  <listitem>
-	    <para>Call-out ports are named
-	      <filename>/dev/cuau<replaceable>N</replaceable></filename>.
-	      Call-out ports are usually not used for terminals, but
-	      are used for modems.  The call-out port can be used if
-	      the serial cable or the terminal does not support the
-	      carrier detect signal.</para>
-	  </listitem>
-	</itemizedlist>
+	    <row>
+	      <entry>RD</entry>
+	      <entry>3</entry>
+	      <entry>connects to</entry>
+	      <entry>2</entry>
+	      <entry>TD</entry>
+	    </row>
+
+	    <row>
+	      <entry>RTS</entry>
+	      <entry>4</entry>
+	      <entry>connects to</entry>
+	      <entry>5</entry>
+	      <entry>CTS</entry>
+	    </row>
+
+	    <row>
+	      <entry>CTS</entry>
+	      <entry>5</entry>
+	      <entry>connects to</entry>
+	      <entry>4</entry>
+	      <entry>RTS</entry>
+	    </row>
+
+	    <row>
+	      <entry>DTR</entry>
+	      <entry>20</entry>
+	      <entry>connects to</entry>
+	      <entry>6</entry>
+	      <entry>DSR</entry>
+	    </row>
+
+	    <row>
+	      <entry>DTR</entry>
+	      <entry>20</entry>
+	      <entry>connects to</entry>
+	      <entry>8</entry>
+	      <entry>DCD</entry>
+	    </row>
+
+	    <row>
+	      <entry>DSR</entry>
+	      <entry>6</entry>
+	      <entry>connects to</entry>
+	      <entry>20</entry>
+	      <entry>DTR</entry>
+	    </row>
+
+	    <row>
+	      <entry>DCD</entry>
+	      <entry>8</entry>
+	      <entry>connects to</entry>
+	      <entry>20</entry>
+	      <entry>DTR</entry>
+	    </row>
+	  </tbody>
+	</tgroup>
+      </table>
+
+      <para>The next two tables show two other common schemes.</para>
+
+      <table frame="none" pgwide="1">
+	<title>DB-9 to DB-9 Null-Modem Cable</title>
+
+	<tgroup cols="5">
+	  <thead>
+	    <row>
+	      <entry align="left">Signal</entry>
+	      <entry align="left">Pin #</entry>
+	      <entry/>
+	      <entry align="left">Pin #</entry>
+	      <entry align="left">Signal</entry>
+	    </row>
+	  </thead>
+
+	  <tbody>
+	    <row>
+	      <entry>RD</entry>
+	      <entry>2</entry>
+	      <entry>connects to</entry>
+	      <entry>3</entry>
+	      <entry>TD</entry>
+	    </row>
 
-	<para>If a terminal is connected to the first serial
-	  port(<filename>COM1</filename>), use
-	  <filename>/dev/ttyu0</filename> to refer to the
-	  terminal.  If the terminal is on the second serial port
-	  (<filename>COM2</filename>), use
-	  <filename>/dev/ttyu1</filename>, and so forth.</para>
-      </sect2>
+	    <row>
+	      <entry>TD</entry>
+	      <entry>3</entry>
+	      <entry>connects to</entry>
+	      <entry>2</entry>
+	      <entry>RD</entry>
+	    </row>
+
+	    <row>
+	      <entry>DTR</entry>
+	      <entry>4</entry>
+	      <entry>connects to</entry>
+	      <entry>6</entry>
+	      <entry>DSR</entry>
+	    </row>
+
+	    <row>
+	      <entry>DTR</entry>
+	      <entry>4</entry>
+	      <entry>connects to</entry>
+	      <entry>1</entry>
+	      <entry>DCD</entry>
+	    </row>
+
+	    <row>
+	      <entry>SG</entry>
+	      <entry>5</entry>
+	      <entry>connects to</entry>
+	      <entry>5</entry>
+	      <entry>SG</entry>
+	    </row>
+
+	    <row>
+	      <entry>DSR</entry>
+	      <entry>6</entry>
+	      <entry>connects to</entry>
+	      <entry>4</entry>
+	      <entry>DTR</entry>
+	    </row>
+
+	    <row>
+	      <entry>DCD</entry>
+	      <entry>1</entry>
+	      <entry>connects to</entry>
+	      <entry>4</entry>
+	      <entry>DTR</entry>
+	    </row>
+
+	    <row>
+	      <entry>RTS</entry>
+	      <entry>7</entry>
+	      <entry>connects to</entry>
+	      <entry>8</entry>
+	      <entry>CTS</entry>
+	    </row>
+
+	    <row>
+	      <entry>CTS</entry>
+	      <entry>8</entry>
+	      <entry>connects to</entry>
+	      <entry>7</entry>
+	      <entry>RTS</entry>
+	    </row>
+	  </tbody>
+	</tgroup>
+      </table>
+
+      <table frame="none" pgwide="1">
+	<title>DB-9 to DB-25 Null-Modem Cable</title>
+
+	<tgroup cols="5">
+	  <thead>
+	    <row>
+	      <entry align="left">Signal</entry>
+	      <entry align="left">Pin #</entry>
+	      <entry/>
+	      <entry align="left">Pin #</entry>
+	      <entry align="left">Signal</entry>
+	    </row>
+	  </thead>
+
+	  <tbody>
+	    <row>
+	      <entry>RD</entry>
+	      <entry>2</entry>
+	      <entry>connects to</entry>
+	      <entry>2</entry>
+	      <entry>TD</entry>
+	    </row>
+
+	    <row>
+	      <entry>TD</entry>
+	      <entry>3</entry>
+	      <entry>connects to</entry>
+	      <entry>3</entry>
+	      <entry>RD</entry>
+	    </row>
+
+	    <row>
+	      <entry>DTR</entry>
+	      <entry>4</entry>
+	      <entry>connects to</entry>
+	      <entry>6</entry>
+	      <entry>DSR</entry>
+	    </row>
+
+	    <row>
+	      <entry>DTR</entry>
+	      <entry>4</entry>
+	      <entry>connects to</entry>
+	      <entry>8</entry>
+	      <entry>DCD</entry>
+	    </row>
+
+	    <row>
+	      <entry>SG</entry>
+	      <entry>5</entry>
+	      <entry>connects to</entry>
+	      <entry>7</entry>
+	      <entry>SG</entry>
+	    </row>
+
+	    <row>
+	      <entry>DSR</entry>
+	      <entry>6</entry>
+	      <entry>connects to</entry>
+	      <entry>20</entry>
+	      <entry>DTR</entry>
+	    </row>
+
+	    <row>
+	      <entry>DCD</entry>
+	      <entry>1</entry>
+	      <entry>connects to</entry>
+	      <entry>20</entry>
+	      <entry>DTR</entry>
+	    </row>
+
+	    <row>
+	      <entry>RTS</entry>
+	      <entry>7</entry>
+	      <entry>connects to</entry>
+	      <entry>5</entry>
+	      <entry>CTS</entry>
+	    </row>
+
+	    <row>
+	      <entry>CTS</entry>
+	      <entry>8</entry>
+	      <entry>connects to</entry>
+	      <entry>4</entry>
+	      <entry>RTS</entry>
+	    </row>
+	  </tbody>
+	</tgroup>
+      </table>
+
+      <note>
+	<para>When one pin at one end connects to a pair of pins at
+	  the other end, it is usually implemented with one short wire
+	  between the pair of pins in their connector and a long wire
+	  to the other single pin.</para>
+      </note>
+
+      <para>The above designs seem to be the most popular.  In
+	another variation, SG connects to SG, TD connects to RD, RTS
+	and CTS connect to DCD, DTR connects to DSR, and
+	vice-versa.</para>
+
+      <indexterm><primary>RS-232C cables</primary></indexterm>
+
+      <para>A standard serial cable passes all of the RS-232C signals
+	straight through.  The <quote>Transmitted Data</quote> pin on
+	one end of the cable goes to the <quote>Transmitted
+	  Data</quote> pin on the other end.  This is the type of
+	cable used to connect a modem to the &os; system, and is also
+	appropriate for some terminals.</para>
+
+      <para>Serial ports are the devices through which data is
+	transferred between the &os; host computer and the terminal.
+	This section describes the kinds of ports that exist and how
+	they are addressed in &os;.</para>
+
+      <para>Several kinds of serial ports exist.  Before purchasing or
+	constructing a cable, make sure it will fit the ports on the
+	terminal and on the &os; system.</para>
+
+      <para>Most terminals have DB-25 ports.  Personal computers may
+	have DB-25 or DB-9 ports.  A multiport serial card may have
+	RJ-12 or RJ-45 ports.</para>
+
+      <para>See the documentation that accompanied the hardware for
+	specifications on the kind of port or visually verify the type
+	of port.</para>
+
+      <para>In &os;, each serial port is accessed through an entry in
+	<filename>/dev</filename>.  There are two different kinds of
+	entries:</para>
+
+      <itemizedlist>
+	<listitem>
+	  <para>Call-in ports are named
+	    <filename>/dev/ttyu<replaceable>N</replaceable></filename>
+	    where <replaceable>N</replaceable> is the port number,
+	    starting from zero.  Generally, the call-in port is used
+	    for terminals.  Call-in ports require that the serial line
+	    assert the Data Carrier Detect (<acronym>DCD</acronym>)
+	    signal to work correctly.</para>
+	</listitem>
+
+	<listitem>
+	  <para>Call-out ports are named
+	    <filename>/dev/cuau<replaceable>N</replaceable></filename>.
+	    Call-out ports are usually not used for terminals, but are
+	    used for modems.  The call-out port can be used if the
+	    serial cable or the terminal does not support the carrier
+	    detect signal.</para>
+	</listitem>
+      </itemizedlist>
+
+      <para>If a terminal is connected to the first serial port
+	(<filename>COM1</filename>), use
+	<filename>/dev/ttyu0</filename> to refer to the terminal.  If
+	the terminal is on the second serial port
+	(<filename>COM2</filename>), use
+	<filename>/dev/ttyu1</filename>, and so forth.</para>
+    </sect2>
 
     <sect2>
       <title>Kernel Configuration</title>
 
       <para>&os; supports four serial ports by default.  In the
-	&ms-dos; world, these are known as
-	<filename>COM1</filename>,
-	<filename>COM2</filename>,
-	<filename>COM3</filename>, and
+	&ms-dos; world, these are known as <filename>COM1</filename>,
+	<filename>COM2</filename>, <filename>COM3</filename>, and
 	<filename>COM4</filename>.  &os; currently supports
 	<quote>dumb</quote> multiport serial interface cards, such as
 	the BocaBoard 1008 and 2016, as well as more intelligent
@@ -505,19 +499,18 @@
 	Technologies.  However, the default kernel only looks for the
 	standard COM ports.</para>
 
-      <para>To see if the kernel recognizes the serial ports,
-	watch for messages while the kernel is booting, or use
-	<command>/sbin/dmesg</command> to replay the kernel's
-	boot messages.  Look for messages that start with the
-	characters <literal>uart</literal>:</para>
+      <para>To see if the kernel recognizes the serial ports, watch
+	for messages while the kernel is booting, or use
+	<command>/sbin/dmesg</command> to replay the kernel's boot
+	messages.  Look for messages that start with the characters
+	<literal>uart</literal>:</para>
 
       <screen>&prompt.root; <userinput>/sbin/dmesg | grep 'uart'</userinput></screen>
 
-      <para>If the kernel does not recognize all of the serial
-	ports, configure <filename>/boot/device.hints</filename>.
-	When editing this file, one can comment out or completely
-	remove lines for devices that do not exist on the
-	system.</para>
+      <para>If the kernel does not recognize all of the serial ports,
+	configure <filename>/boot/device.hints</filename>.  When
+	editing this file, one can comment out or completely remove
+	lines for devices that do not exist on the system.</para>
 
       <note>
 	<para><literal>port IO_COM1</literal> is a substitution for
@@ -528,11 +521,10 @@
 	  addresses for their respective serial ports and interrupts
 	  4, 3, 5, and 9 are fairly common interrupt request lines.
 	  Regular serial ports <emphasis>cannot</emphasis> share
-	  interrupts on ISA-bus PCs.  Multiport boards have
-	  on-board electronics that allow all the 16550A's on the
-	  board to share one or two interrupt request lines.</para>
+	  interrupts on ISA-bus PCs.  Multiport boards have on-board
+	  electronics that allow all the 16550A's on the board to
+	  share one or two interrupt request lines.</para>
       </note>
-
     </sect2>
 
     <sect2>
@@ -614,7 +606,8 @@
 	of the port will be stuck with 57600&nbsp;bps.</para>
 
       <para>The initial state and lock state devices should only be
-	writable by <systemitem class="username">root</systemitem>.</para>
+	writable by <systemitem
+	  class="username">root</systemitem>.</para>
     </sect2>
   </sect1>
 
@@ -641,9 +634,9 @@
       connected network.  This section describes how to use terminals
       with &os;.</para>
 
-    <para>The original &unix; systems did not have consoles.
-      Instead, users logged in and ran programs through terminals
-      that were connected to the computer's serial ports.</para>
+    <para>The original &unix; systems did not have consoles.  Instead,
+      users logged in and ran programs through terminals that were
+      connected to the computer's serial ports.</para>
 
     <para>The ability to establish a login session on a serial port
       still exists in nearly every &unix;-like operating system
@@ -668,17 +661,18 @@
 	    to computers over serial lines.  They are called
 	    <quote>dumb</quote> because they have only enough
 	    computational power to display, send, and receive text.
-	    No programs can be run on these devices.  Instead, dumb terminals
-	    connect to a computer that runs the needed programs.</para>
-
-	  <para>There are hundreds of kinds of dumb terminals made
-	    by many manufacturers, and just about any kind will work
-	    with &os;.  Some high-end terminals can even display
-	    graphics, but only certain software packages can take
-	    advantage of these advanced features.</para>
+	    No programs can be run on these devices.  Instead, dumb
+	    terminals connect to a computer that runs the needed
+	    programs.</para>
+
+	  <para>There are hundreds of kinds of dumb terminals made by
+	    many manufacturers, and just about any kind will work with
+	    &os;.  Some high-end terminals can even display graphics,
+	    but only certain software packages can take advantage of
+	    these advanced features.</para>
 
-	  <para>Dumb terminals are popular in work environments
-	    where workers do not need access to graphical
+	  <para>Dumb terminals are popular in work environments where
+	    workers do not need access to graphical
 	    applications.</para>
 	</listitem>
       </varlistentry>
@@ -689,9 +683,8 @@
 	  <para>Since a dumb terminal has just enough ability to
 	    display, send, and receive text, any spare computer can
 	    be a dumb terminal.  All that is needed is the proper
-	    cable and some <firstterm>terminal
-	    emulation</firstterm> software to run on the
-	    computer.</para>
+	    cable and some <firstterm>terminal emulation</firstterm>
+	    software to run on the computer.</para>
 
 	  <para>This configuration can be useful.  For example, if one
 	    user is busy working at the &os; system's console, another
@@ -703,25 +696,27 @@
 	    &os; that can be used to work through a serial connection:
 	    &man.cu.1; and &man.tip.1;.</para>
 
-	  <para>For example, to connect from a client system that runs &os; to the
-	    serial connection of another system:</para>
+	  <para>For example, to connect from a client system that runs
+	    &os; to the serial connection of another system:</para>
 
 	  <screen>&prompt.root; <userinput>cu -l <replaceable>serial-port-device</replaceable></userinput></screen>
 
-	  <para>Replace <replaceable>serial-port-device</replaceable> with the device name of
-	    the connected serial port.  These device files are called
+	  <para>Replace <replaceable>serial-port-device</replaceable>
+	    with the device name of the connected serial port.  These
+	    device files are called
 	    <filename>/dev/cuau<replaceable>N</replaceable></filename>
 	    on &os; versions 8.x and lower and
 	    <filename>/dev/cuad<replaceable>N</replaceable></filename>
 	    on &os; versions 9.x and higher.  In either case,
-	    <replaceable>N</replaceable> is the
-	    serial port number, starting from zero.
-	      This means that <filename>COM1</filename>
-	      is <filename>/dev/cuau0</filename> or
-	      <filename>/dev/cuad0</filename> in &os;.</para>
-
-	    <para>Additional programs are available
-	      through the Ports Collection, such as <package>comms/minicom</package>.</para>
+	    <replaceable>N</replaceable> is the serial port number,
+	    starting from zero.  This means that
+	    <filename>COM1</filename> is
+	    <filename>/dev/cuau0</filename> or
+	    <filename>/dev/cuad0</filename> in &os;.</para>
+
+	  <para>Additional programs are available through the Ports
+	    Collection, such as

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