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diff --git a/static/freebsd/man4/pcf8574.4 3.html b/static/freebsd/man4/pcf8574.4 3.html new file mode 100644 index 00000000..0aea0ef5 --- /dev/null +++ b/static/freebsd/man4/pcf8574.4 3.html @@ -0,0 +1,79 @@ +<table class="head"> + <tr> + <td class="head-ltitle">PCF8574(4)</td> + <td class="head-vol">Device Drivers Manual</td> + <td class="head-rtitle">PCF8574(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">pcf8574</code> — <span class="Nd">driver + for the PCF8574 8-bit I2C IO expander</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> +<p class="Pp">To compile this driver into the kernel, place the following lines + in your kernel configuration file:</p> +<div class="Bd Pp Bd-indent"><code class="Cd">device pcf8574</code> +<br/> +<code class="Cd">device gpio</code> +<br/> +<code class="Cd">device iicbus</code></div> +<p class="Pp">Alternatively, to load the driver as a module at boot time, place + the following line in <a class="Xr">loader.conf(5)</a>:</p> +<div class="Bd Pp Bd-indent Li"> +<pre>pcf8574_load="YES"</pre> +</div> +</section> +<section class="Sh"> +<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> +<p class="Pp">The <code class="Nm">pcf8574</code> driver provides + <a class="Xr">gpiobus(4)</a> control over 8 GPIO pins. The pins are + quasi-bidirectional. Only low output can be actively driven. High output is + equivalent to input.</p> +<p class="Pp">On an <a class="Xr">FDT(4)</a> based system the following + properties must be set:</p> +<dl class="Bl-tag"> + <dt id="compatible"><var class="Va">compatible</var></dt> + <dd>Must be set to "nxp,pcf8574".</dd> + <dt id="reg"><var class="Va">reg</var></dt> + <dd>The I2C address of <code class="Nm">pcf8574</code>.</dd> +</dl> +<p class="Pp">The DTS part for a <code class="Nm">pcf8574</code> device usually + looks like:</p> +<div class="Bd Pp Li"> +<pre>/ { + + ... + pcf8574@27 { + compatible = "nxp,pcf8574"; + reg = <0x27>; + }; +};</pre> +</div> +</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">fdt(4)</a>, <a class="Xr">gpiobus(4)</a>, + <a class="Xr">iicbus(4)</a></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">pcf8574</code> driver and this manual page + was written by <span class="An">Andriy Gapon</span> + <<a class="Mt" href="mailto:avg@FreeBSD.org">avg@FreeBSD.org</a>>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="BUGS"><a class="permalink" href="#BUGS">BUGS</a></h1> +<p class="Pp">The <code class="Nm">pcf8574</code> driver does not support the + input change interrupt that the hardware provides.</p> +</section> +</div> +<table class="foot"> + <tr> + <td class="foot-date">November 6, 2021</td> + <td class="foot-os">FreeBSD 15.0</td> + </tr> +</table> |