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<table class="head">
<tr>
<td class="head-ltitle">MCP48X1DAC(4)</td>
<td class="head-vol">Device Drivers Manual</td>
<td class="head-rtitle">MCP48X1DAC(4)</td>
</tr>
</table>
<div class="manual-text">
<section class="Sh">
<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1>
<p class="Pp"><code class="Nm">mcp48x1dac</code> —
<span class="Nd">Microchip 48x1 digital to analog converter</span></p>
</section>
<section class="Sh">
<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1>
<p class="Pp"><code class="Cd">mcp48x1dac* at spi? slave ? flags N</code></p>
</section>
<section class="Sh">
<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1>
<p class="Pp">The <code class="Nm">mcp48x1dac</code> driver supports the MCP48x1
family of digital to analog converters. The digital values to be converted
to analog signal are passed through the <a class="Xr">sysctl(8)</a>
node.</p>
<p class="Pp">The driver reports the current voltage output on the chip's DAC
channel through the <a class="Xr">envsys(4)</a> API. It calculates these
values assuming that internal 2.048V reference voltage
(<code class="Li">Vref</code>) is used.</p>
<p class="Pp">The following table shows the supported chips. The type of the
chip can be selected with the <var class="Ar">flags</var> argument in the
config file.</p>
<table class="Bl-column Bd-indent">
<tr id="Designation">
<td><a class="permalink" href="#Designation"><b class="Sy">Designation</b></a></td>
<td><a class="permalink" href="#Resolution"><b class="Sy" id="Resolution">Resolution</b></a></td>
<td><a class="permalink" href="#flags"><b class="Sy" id="flags">flags</b></a></td>
</tr>
<tr id="MCP4801">
<td><a class="permalink" href="#MCP4801"><code class="Li">MCP4801</code></a></td>
<td>8 bits</td>
<td>0</td>
</tr>
<tr id="MCP4811">
<td><a class="permalink" href="#MCP4811"><code class="Li">MCP4811</code></a></td>
<td>10 bits</td>
<td>1</td>
</tr>
<tr id="MCP4821">
<td><a class="permalink" href="#MCP4821"><code class="Li">MCP4821</code></a></td>
<td>12 bits</td>
<td>2</td>
</tr>
</table>
</section>
<section class="Sh">
<h1 class="Sh" id="SYSCTL_VARIABLES"><a class="permalink" href="#SYSCTL_VARIABLES">SYSCTL
VARIABLES</a></h1>
<p class="Pp">The following <a class="Xr">sysctl(3)</a> variables are
provided:</p>
<dl class="Bl-tag">
<dt>machdep.mcp48x1dac0.data</dt>
<dd>Defines digital data to be converted into analog signal. This value is
interpreted literally and sent to the DAC without any conversion. Refer to
the chip datasheet for more information.</dd>
<dt>machdep.mcp48x1dac0.gain</dt>
<dd>When set to 1 it enables 2x output gain on the DAC channel. The default
value is 0.</dd>
</dl>
</section>
<section class="Sh">
<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE
ALSO</a></h1>
<p class="Pp"><a class="Xr">envsys(4)</a>, <a class="Xr">spi(4)</a>,
<a class="Xr">sysctl(8)</a></p>
<p class="Pp"><cite class="Rs"><span class="RsT">MCP4801/4811/4821 8/10/12-Bit
Voltage Output Digital-to-Analog Converter with Internal VREF and SPI
Interface Data Sheet</span>.</cite></p>
</section>
<section class="Sh">
<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1>
<p class="Pp">The <code class="Nm">mcp48x1dac</code> driver first appeared in
<span class="Ux">NetBSD 7.0</span>.</p>
</section>
<section class="Sh">
<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1>
<p class="Pp">The <code class="Nm">mcp48x1dac</code> driver was written by
<span class="An">Radoslaw Kujawa</span>.</p>
<p class="Pp">This man page is based on <a class="Xr">mcp3kadc(4)</a> page by
<span class="An">Frank Wille</span>.</p>
</section>
<section class="Sh">
<h1 class="Sh" id="BUGS"><a class="permalink" href="#BUGS">BUGS</a></h1>
<p class="Pp">There are bugs.</p>
</section>
</div>
<table class="foot">
<tr>
<td class="foot-date">August 23, 2015</td>
<td class="foot-os">NetBSD 10.1</td>
</tr>
</table>
|
