printing-intro-setup.html

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<p><b>注:</b> FreeBSD&nbsp;5.0 includes the <var class="LITERAL">devfs</var> filesystem
which automatically creates device nodes as needed. If you are running a version of
FreeBSD with <var class="LITERAL">devfs</var> enabled then you can safely skip this
section.</p>
</blockquote>
</div>

<p>Even though the kernel may support communication along a serial or parallel port, you
will still need a software interface through which programs running on the system can
send and receive data. That is what entries in the <tt class="FILENAME">/dev</tt>
directory are for.</p>

<p><span class="emphasis"><i class="EMPHASIS">To add a <tt class="FILENAME">/dev</tt>
entry for a port:</i></span></p>

<div class="PROCEDURE">
<ol type="1">
<li>
<p>Become <tt class="USERNAME">root</tt> with the <span class="CITEREFENTRY"><span
class="REFENTRYTITLE">su</span>(1)</span> command. Enter the <tt
class="USERNAME">root</tt> password when prompted.</p>
</li>

<li>
<p>Change to the <tt class="FILENAME">/dev</tt> directory:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">cd /dev</kbd>
</pre>
</li>

<li>
<p>Type:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">./MAKEDEV <var
class="REPLACEABLE">port</var></kbd>
</pre>

<p>Where <var class="REPLACEABLE">port</var> is the device entry for the port you want to
make. Use <var class="LITERAL">lpt0</var> for the printer on the first parallel port,
<var class="LITERAL">lpt1</var> for the printer on the second port, and so on; use <var
class="LITERAL">ttyd0</var> for the first serial port, <var class="LITERAL">ttyd1</var>
for the second, and so on.</p>
</li>

<li>
<p>Type:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">ls -l <var
class="REPLACEABLE">port</var></kbd>
</pre>

<p>to make sure the device entry got created.</p>
</li>
</ol>
</div>

<div class="SECT4">
<h4 class="SECT4"><a id="PRINTING-PARALLEL-PORT-MODE"
name="PRINTING-PARALLEL-PORT-MODE">9.3.1.3.1. Setting the Communication Mode for the
Parallel Port</a></h4>

<p>When you are using the parallel interface, you can choose whether FreeBSD should use
interrupt-driven or polled communication with the printer. The generic printer device
driver (<span class="CITEREFENTRY"><span class="REFENTRYTITLE">lpt</span>(4)</span>) on
FreeBSD&nbsp;4.X and 5.X uses the <span class="CITEREFENTRY"><span
class="REFENTRYTITLE">ppbus</span>(4)</span> system, which controls the port chipset with
the <span class="CITEREFENTRY"><span class="REFENTRYTITLE">ppc</span>(4)</span>
driver.</p>

<ul>
<li>
<p>The <span class="emphasis"><i class="EMPHASIS">interrupt-driven</i></span> method is
the default with the GENERIC kernel. With this method, the operating system uses an IRQ
line to determine when the printer is ready for data.</p>
</li>

<li>
<p>The <span class="emphasis"><i class="EMPHASIS">polled</i></span> method directs the
operating system to repeatedly ask the printer if it is ready for more data. When it
responds ready, the kernel sends more data.</p>
</li>
</ul>

<p>The interrupt-driven method is usually somewhat faster but uses up a precious IRQ
line. Some newer HP printers are claimed not to work correctly in interrupt mode,
apparently due to some (not yet exactly understood) timing problem. These printers need
polled mode. You should use whichever one works. Some printers will work in both modes,
but are painfully slow in interrupt mode.</p>

<p>You can set the communications mode in two ways: by configuring the kernel or by using
the <span class="CITEREFENTRY"><span class="REFENTRYTITLE">lptcontrol</span>(8)</span>
program.</p>

<p><span class="emphasis"><i class="EMPHASIS">To set the communications mode by
configuring the kernel:</i></span></p>

<div class="PROCEDURE">
<ol type="1">
<li>
<p>Edit your kernel configuration file. Look for an <var class="LITERAL">ppc0</var>
entry. If you are setting up the second parallel port, use <var
class="LITERAL">ppc1</var> instead. Use <var class="LITERAL">ppc2</var> for the third
port, and so on.</p>

<ul>
<li>
<p>If you want interrupt-driven mode, for FreeBSD&nbsp;4.X add the <var
class="LITERAL">irq</var> specifier:</p>

<pre class="PROGRAMLISTING">
device ppc0 at isa? irq <var class="REPLACEABLE">N</var>
</pre>

<p>Where <var class="REPLACEABLE">N</var> is the IRQ number for your computer's parallel
port.</p>

<p>For FreeBSD&nbsp;5.X, edit the following line:</p>

<pre class="PROGRAMLISTING">
hint.ppc.0.irq="<var class="REPLACEABLE">N</var>"
</pre>

<p>in the <tt class="FILENAME">/boot/device.hints</tt> file and replace <var
class="REPLACEABLE">N</var> with the right IRQ number. The kernel configuration file must
also contain the <span class="CITEREFENTRY"><span
class="REFENTRYTITLE">ppc</span>(4)</span> driver:</p>

<pre class="SCREEN">
device ppc
</pre>
</li>

<li>
<p>If you want polled mode, do not add the <var class="LITERAL">irq</var> specifier:</p>

<p>For FreeBSD&nbsp;4.X, use the following line in your kernel configuration file:</p>

<pre class="PROGRAMLISTING">
device ppc0 at isa?
</pre>

<p>For FreeBSD&nbsp;5.X, simply remove in your <tt
class="FILENAME">/boot/device.hints</tt> file, the following line:</p>

<pre class="PROGRAMLISTING">
hint.ppc.0.irq="<var class="REPLACEABLE">N</var>"
</pre>

<p>In some cases, this is not enough to put the port in polled mode under
FreeBSD&nbsp;5.X. Most of time it comes from <span class="CITEREFENTRY"><span
class="REFENTRYTITLE">acpi</span>(4)</span> driver, this latter is able to probe and
attach devices, and therefore, control the access mode to the printer port. You should
check your <span class="CITEREFENTRY"><span class="REFENTRYTITLE">acpi</span>(4)</span>
configuration to correct this problem.</p>
</li>
</ul>
</li>

<li>
<p>Save the file. Then configure, build, and install the kernel, then reboot. See <a
href="kernelconfig.html">kernel configuration</a> for more details.</p>
</li>
</ol>
</div>

<p><span class="emphasis"><i class="EMPHASIS">To set the communications mode
with</i></span> <span class="CITEREFENTRY"><span
class="REFENTRYTITLE">lptcontrol</span>(8)</span>:</p>

<div class="PROCEDURE">
<ol type="1">
<li>
<p>Type:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">lptcontrol -i -d /dev/lpt<var
class="REPLACEABLE">N</var></kbd>
</pre>

<p>to set interrupt-driven mode for <var class="LITERAL">lpt<var
class="REPLACEABLE">N</var></var>.</p>
</li>

<li>
<p>Type:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">lptcontrol -p -d /dev/lpt<var
class="REPLACEABLE">N</var></kbd>
</pre>

<p>to set polled-mode for <var class="LITERAL">lpt<var
class="REPLACEABLE">N</var></var>.</p>
</li>
</ol>
</div>

<p>You could put these commands in your <tt class="FILENAME">/etc/rc.local</tt> file to
set the mode each time your system boots. See <span class="CITEREFENTRY"><span
class="REFENTRYTITLE">lptcontrol</span>(8)</span> for more information.</p>
</div>

<div class="SECT4">
<h4 class="SECT4"><a id="PRINTING-TESTING" name="PRINTING-TESTING">9.3.1.3.2. Checking
Printer Communications</a></h4>

<p>Before proceeding to configure the spooling system, you should make sure the operating
system can successfully send data to your printer. It is a lot easier to debug printer
communication and the spooling system separately.</p>

<p>To test the printer, we will send some text to it. For printers that can immediately
print characters sent to them, the program <span class="CITEREFENTRY"><span
class="REFENTRYTITLE">lptest</span>(1)</span> is perfect: it generates all 96 printable
ASCII characters in 96 lines.</p>

<p>For a <span class="TRADEMARK">PostScript</span> (or other language-based) printer, we
will need a more sophisticated test. A small <span class="TRADEMARK">PostScript</span>
program, such as the following, will suffice:</p>

<pre class="PROGRAMLISTING">
%!PS
100 100 moveto 300 300 lineto stroke
310 310 moveto /Helvetica findfont 12 scalefont setfont
(Is this thing working?) show
showpage
</pre>

<p>The above <span class="TRADEMARK">PostScript</span> code can be placed into a file and
used as shown in the examples appearing in the following sections.</p>

<div class="NOTE">
<blockquote class="NOTE">
<p><b>注:</b> When this document refers to a printer language, it is assuming a language
like <span class="TRADEMARK">PostScript</span>, and not Hewlett Packard's PCL. Although
PCL has great functionality, you can intermingle plain text with its escape sequences.
<span class="TRADEMARK">PostScript</span> cannot directly print plain text, and that is
the kind of printer language for which we must make special accommodations.</p>
</blockquote>
</div>

<div class="SECT5">
<h5 class="SECT5"><a id="PRINTING-CHECKING-PARALLEL"
name="PRINTING-CHECKING-PARALLEL">9.3.1.3.2.1. Checking a Parallel Printer</a></h5>

<p>This section tells you how to check if FreeBSD can communicate with a printer
connected to a parallel port.</p>

<p><span class="emphasis"><i class="EMPHASIS">To test a printer on a parallel
port:</i></span></p>

<div class="PROCEDURE">
<ol type="1">
<li>
<p>Become <tt class="USERNAME">root</tt> with <span class="CITEREFENTRY"><span
class="REFENTRYTITLE">su</span>(1)</span>.</p>
</li>

<li>
<p>Send data to the printer.</p>

<ul>
<li>
<p>If the printer can print plain text, then use <span class="CITEREFENTRY"><span
class="REFENTRYTITLE">lptest</span>(1)</span>. Type:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">lptest &gt; /dev/lpt<var
class="REPLACEABLE">N</var></kbd>
</pre>

<p>Where <var class="REPLACEABLE">N</var> is the number of the parallel port, starting
from zero.</p>
</li>

<li>
<p>If the printer understands <span class="TRADEMARK">PostScript</span> or other printer
language, then send a small program to the printer. Type:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">cat &gt; /dev/lpt<var
class="REPLACEABLE">N</var></kbd>
</pre>

<p>Then, line by line, type the program <span class="emphasis"><i
class="EMPHASIS">carefully</i></span> as you cannot edit a line once you have pressed
<var class="LITERAL">RETURN</var> or <var class="LITERAL">ENTER</var>. When you have
finished entering the program, press <var class="LITERAL">CONTROL+D</var>, or whatever
your end of file key is.</p>

<p>Alternatively, you can put the program in a file and type:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">cat <var
class="REPLACEABLE">file</var> &gt; /dev/lpt<var class="REPLACEABLE">N</var></kbd>
</pre>

<p>Where <var class="REPLACEABLE">file</var> is the name of the file containing the
program you want to send to the printer.</p>
</li>
</ul>
</li>
</ol>
</div>

<p>You should see something print. Do not worry if the text does not look right; we will
fix such things later.</p>
</div>

<div class="SECT5">
<h5 class="SECT5"><a id="PRINTING-CHECKING-SERIAL"
name="PRINTING-CHECKING-SERIAL">9.3.1.3.2.2. Checking a Serial Printer</a></h5>