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<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Blocking SPI master mode traits."><title>embedded_hal::spi - Rust</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-46f98efaafac5295.ttf.woff2,FiraSans-Regular-018c141bf0843ffd.woff2,FiraSans-Medium-8f9a781e4970d388.woff2,SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2,SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../../static.files/normalize-76eba96aa4d2e634.css"><link rel="stylesheet" href="../../static.files/rustdoc-492a78a4a87dcc01.css"><meta name="rustdoc-vars" data-root-path="../../" data-static-root-path="../../static.files/" data-current-crate="embedded_hal" data-themes="" data-resource-suffix="" data-rustdoc-version="1.82.0 (f6e511eec 2024-10-15)" data-channel="1.82.0" data-search-js="search-a99f1315e7cc5121.js" data-settings-js="settings-4313503d2e1961c2.js" ><script src="../../static.files/storage-118b08c4c78b968e.js"></script><script defer src="../sidebar-items.js"></script><script defer src="../../static.files/main-921df33f47b8780c.js"></script><noscript><link rel="stylesheet" href="../../static.files/noscript-3b12f09e550e0385.css"></noscript><link rel="alternate icon" type="image/png" href="../../static.files/favicon-32x32-422f7d1d52889060.png"><link rel="icon" type="image/svg+xml" href="../../static.files/favicon-2c020d218678b618.svg"></head><body class="rustdoc mod"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="mobile-topbar"><button class="sidebar-menu-toggle" title="show sidebar"></button></nav><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../embedded_hal/index.html">embedded_<wbr>hal</a><span class="version">1.0.0</span></h2></div><h2 class="location"><a href="#">Module spi</a></h2><div class="sidebar-elems"><section><ul class="block"><li><a href="#structs">Structs</a></li><li><a href="#enums">Enums</a></li><li><a href="#constants">Constants</a></li><li><a href="#traits">Traits</a></li></ul></section><h2><a href="../index.html">In crate embedded_<wbr>hal</a></h2></div></nav><div class="sidebar-resizer"></div><main><div class="width-limiter"><rustdoc-search></rustdoc-search><section id="main-content" class="content"><div class="main-heading"><h1>Module <a href="../index.html">embedded_hal</a>::<wbr><a class="mod" href="#">spi</a><button id="copy-path" title="Copy item path to clipboard">Copy item path</button></h1><span class="out-of-band"><a class="src" href="../../src/embedded_hal/spi.rs.html#1-506">source</a> · <button id="toggle-all-docs" title="collapse all docs">[<span>−</span>]</button></span></div><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Blocking SPI master mode traits.</p>
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<h2 id="bus-vs-device"><a class="doc-anchor" href="#bus-vs-device">§</a>Bus vs Device</h2>
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<p>SPI allows sharing a single bus between many SPI devices. The SCK, MOSI and MISO lines are
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wired in parallel to all the devices, and each device gets a dedicated chip-select (CS) line from the MCU, like this:</p>
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"><div style="display: inline-block; font-size: 12px; font-family: Helvetica; color: rgb(240, 240, 240); line-height: 1.2; pointer-events: all; font-weight: bold; white-space: normal; overflow-wrap: normal;"><div>SPI DEVICE 2</div></div></div></div></foreignObject><text x="300" y="194" fill="rgb(240, 240, 240)" font-family="Helvetica" font-size="12px" text-anchor="middle" font-weight="bold">SPI DEVICE 2</text></switch></g><path d="M 139.76 69.95 L 233.63 69.92" fill="none" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="stroke"/><path d="M 238.88 69.92 L 231.88 73.42 L 233.63 69.92 L 231.88 66.42 Z" fill="rgb(240, 240, 240)" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="all"/><path d="M 141.08 109.85 L 190 110 L 233.63 109.85" fill="none" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="stroke"/><path d="M 238.88 109.83 L 231.89 113.36 L 233.63 109.85 L 231.87 106.36 Z" fill="rgb(240, 240, 240)" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="all"/><path d="M 141 130 L 232.31 130.35" fill="none" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="stroke"/><path d="M 237.56 130.37 L 230.55 133.84 L 232.31 130.35 L 230.58 126.84 Z" fill="rgb(240, 240, 240)" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="all"/><path d="M 141 149.69 L 160 150 L 160 281 L 233.15 280.66" fill="none" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="stroke"/><path d="M 238.4 280.64 L 231.42 284.17 L 233.15 280.66 L 231.39 277.17 Z" fill="rgb(240, 240, 240)" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="all"/><path d="M 180 113 L 180 260 L 233.63 259.73" fill="none" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="stroke"/><ellipse cx="180" cy="110" rx="3" ry="3" fill="rgb(240, 240, 240)" stroke="rgb(240, 240, 240)" pointer-events="all"/><path d="M 238.88 259.71 L 231.9 263.24 L 233.63 259.73 L 231.86 256.24 Z" fill="rgb(240, 240, 240)" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="all"/><path d="M 237.72 238.77 L 200 239 L 200 93" fill="none" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="stroke"/><ellipse cx="200" cy="90" rx="3" ry="3" fill="rgb(240, 240, 240)" stroke="rgb(240, 240, 240)" pointer-events="all"/><path d="M 240.96 89.94 L 146.37 90" fill="none" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="stroke"/><path d="M 141.12 90 L 148.12 86.5 L 146.37 90 L 148.12 93.5 Z" fill="rgb(240, 240, 240)" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="all"/><path d="M 220 73 L 220 220 L 233.63 220.03" fill="none" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="stroke"/><ellipse cx="220" cy="70" rx="3" ry="3" fill="rgb(240, 240, 240)" stroke="rgb(240, 240, 240)" pointer-events="all"/><path d="M 238.88 220.05 L 231.87 223.53 L 233.63 220.03 L 231.89 216.53 Z" fill="rgb(240, 240, 240)" stroke="rgb(240, 240, 240)" stroke-miterlimit="10" pointer-events="all"/></g><switch><g requiredFeatures="http://www.w3.org/TR/SVG11/feature#Extensibility"/><a transform="translate(0,-5)" xlink:href="https://www.diagrams.net/doc/faq/svg-export-text-problems" target="_blank"><text text-anchor="middle" font-size="10px" x="50%" y="100%">Text is not SVG - cannot display</text></a></switch></svg></p>
|
||
<p>CS is usually active-low. When CS is high (not asserted), SPI devices ignore all incoming data, and
|
||
don’t drive MISO. When CS is low (asserted), the device is active: reacts to incoming data on MOSI and
|
||
drives MISO with the response data. By asserting one CS or another, the MCU can choose to which
|
||
SPI device it “talks” to on the (possibly shared) bus.</p>
|
||
<p>This bus sharing is common when having multiple SPI devices in the same board, since it uses fewer MCU
|
||
pins (<code>n+3</code> instead of <code>4*n</code>), and fewer MCU SPI peripherals (<code>1</code> instead of <code>n</code>).</p>
|
||
<p>However, it poses a challenge when building portable drivers for SPI devices. The driver needs to
|
||
be able to talk to its device on the bus, while not interfering with other drivers talking to other
|
||
devices.</p>
|
||
<p>To solve this, <code>embedded-hal</code> has two kinds of SPI traits: <strong>SPI bus</strong> and <strong>SPI device</strong>.</p>
|
||
<h3 id="bus"><a class="doc-anchor" href="#bus">§</a>Bus</h3>
|
||
<p>The <a href="trait.SpiBus.html" title="trait embedded_hal::spi::SpiBus"><code>SpiBus</code></a> trait represents <strong>exclusive ownership</strong> over the whole SPI bus. This is usually the entire
|
||
SPI MCU peripheral, plus the SCK, MOSI and MISO pins.</p>
|
||
<p>Owning an instance of an SPI bus guarantees exclusive access, this is, we have the guarantee no other
|
||
piece of code will try to use the bus while we own it.</p>
|
||
<h3 id="device"><a class="doc-anchor" href="#device">§</a>Device</h3>
|
||
<p>The <a href="trait.SpiDevice.html" title="trait embedded_hal::spi::SpiDevice"><code>SpiDevice</code></a> trait represents <strong>ownership over a single SPI device selected by a CS pin</strong> in a (possibly shared) bus. This is typically:</p>
|
||
<ul>
|
||
<li>Exclusive ownership of the <strong>CS pin</strong>.</li>
|
||
<li>Access to the <strong>underlying SPI bus</strong>. If shared, it’ll be behind some kind of lock/mutex.</li>
|
||
</ul>
|
||
<p>An <a href="trait.SpiDevice.html" title="trait embedded_hal::spi::SpiDevice"><code>SpiDevice</code></a> allows initiating <a href="trait.SpiDevice.html#tymethod.transaction" title="method embedded_hal::spi::SpiDevice::transaction">transactions</a> against the target device on the bus. A transaction
|
||
consists of asserting CS, then doing one or more transfers, then deasserting CS. For the entire duration of the transaction, the <a href="trait.SpiDevice.html" title="trait embedded_hal::spi::SpiDevice"><code>SpiDevice</code></a>
|
||
implementation will ensure no other transaction can be opened on the same bus. This is the key that allows correct sharing of the bus.</p>
|
||
<h2 id="for-driver-authors"><a class="doc-anchor" href="#for-driver-authors">§</a>For driver authors</h2>
|
||
<p>When implementing a driver, it’s crucial to pick the right trait, to ensure correct operation
|
||
with maximum interoperability. Here are some guidelines depending on the device you’re implementing a driver for:</p>
|
||
<p>If your device <strong>has a CS pin</strong>, use <a href="trait.SpiDevice.html" title="trait embedded_hal::spi::SpiDevice"><code>SpiDevice</code></a>. Do not manually
|
||
manage the CS pin, the <a href="trait.SpiDevice.html" title="trait embedded_hal::spi::SpiDevice"><code>SpiDevice</code></a> implementation will do it for you.
|
||
By using <a href="trait.SpiDevice.html" title="trait embedded_hal::spi::SpiDevice"><code>SpiDevice</code></a>, your driver will cooperate nicely with other drivers for other devices in the same shared SPI bus.</p>
|
||
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">pub struct </span>MyDriver<SPI> {
|
||
spi: SPI,
|
||
}
|
||
|
||
<span class="kw">impl</span><SPI> MyDriver<SPI>
|
||
<span class="kw">where
|
||
</span>SPI: SpiDevice,
|
||
{
|
||
<span class="kw">pub fn </span>new(spi: SPI) -> <span class="self">Self </span>{
|
||
<span class="self">Self </span>{ spi }
|
||
}
|
||
|
||
<span class="kw">pub fn </span>read_foo(<span class="kw-2">&mut </span><span class="self">self</span>) -> <span class="prelude-ty">Result</span><[u8; <span class="number">2</span>], MyError<SPI::Error>> {
|
||
<span class="kw">let </span><span class="kw-2">mut </span>buf = [<span class="number">0</span>; <span class="number">2</span>];
|
||
|
||
<span class="comment">// `transaction` asserts and deasserts CS for us. No need to do it manually!
|
||
</span><span class="self">self</span>.spi.transaction(<span class="kw-2">&mut </span>[
|
||
Operation::Write(<span class="kw-2">&</span>[<span class="number">0x90</span>]),
|
||
Operation::Read(<span class="kw-2">&mut </span>buf),
|
||
]).map_err(MyError::Spi)<span class="question-mark">?</span>;
|
||
|
||
<span class="prelude-val">Ok</span>(buf)
|
||
}
|
||
}
|
||
|
||
<span class="attr">#[derive(Copy, Clone, Debug)]
|
||
</span><span class="kw">enum </span>MyError<SPI> {
|
||
Spi(SPI),
|
||
<span class="comment">// Add other errors for your driver here.
|
||
</span>}</code></pre></div>
|
||
<p>If your device <strong>does not have a CS pin</strong>, use <a href="trait.SpiBus.html" title="trait embedded_hal::spi::SpiBus"><code>SpiBus</code></a>. This will ensure
|
||
your driver has exclusive access to the bus, so no other drivers can interfere. It’s not possible to safely share
|
||
a bus without CS pins. By requiring <a href="trait.SpiBus.html" title="trait embedded_hal::spi::SpiBus"><code>SpiBus</code></a> you disallow sharing, ensuring correct operation.</p>
|
||
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">pub struct </span>MyDriver<SPI> {
|
||
spi: SPI,
|
||
}
|
||
|
||
<span class="kw">impl</span><SPI> MyDriver<SPI>
|
||
<span class="kw">where
|
||
</span>SPI: SpiBus,
|
||
{
|
||
<span class="kw">pub fn </span>new(spi: SPI) -> <span class="self">Self </span>{
|
||
<span class="self">Self </span>{ spi }
|
||
}
|
||
|
||
<span class="kw">pub fn </span>read_foo(<span class="kw-2">&mut </span><span class="self">self</span>) -> <span class="prelude-ty">Result</span><[u8; <span class="number">2</span>], MyError<SPI::Error>> {
|
||
<span class="kw">let </span><span class="kw-2">mut </span>buf = [<span class="number">0</span>; <span class="number">2</span>];
|
||
<span class="self">self</span>.spi.write(<span class="kw-2">&</span>[<span class="number">0x90</span>]).map_err(MyError::Spi)<span class="question-mark">?</span>;
|
||
<span class="self">self</span>.spi.read(<span class="kw-2">&mut </span>buf).map_err(MyError::Spi)<span class="question-mark">?</span>;
|
||
<span class="prelude-val">Ok</span>(buf)
|
||
}
|
||
}
|
||
|
||
<span class="attr">#[derive(Copy, Clone, Debug)]
|
||
</span><span class="kw">enum </span>MyError<SPI> {
|
||
Spi(SPI),
|
||
<span class="comment">// Add other errors for your driver here.
|
||
</span>}</code></pre></div>
|
||
<p>If you’re (ab)using SPI to <strong>implement other protocols</strong> by bitbanging (WS2812B, onewire, generating arbitrary waveforms…), use <a href="trait.SpiBus.html" title="trait embedded_hal::spi::SpiBus"><code>SpiBus</code></a>.
|
||
SPI bus sharing doesn’t make sense at all in this case. By requiring <a href="trait.SpiBus.html" title="trait embedded_hal::spi::SpiBus"><code>SpiBus</code></a> you disallow sharing, ensuring correct operation.</p>
|
||
<h2 id="for-hal-authors"><a class="doc-anchor" href="#for-hal-authors">§</a>For HAL authors</h2>
|
||
<p>HALs <strong>must</strong> implement <a href="trait.SpiBus.html" title="trait embedded_hal::spi::SpiBus"><code>SpiBus</code></a>. Users can combine the bus together with the CS pin (which should
|
||
implement <a href="../digital/trait.OutputPin.html" title="trait embedded_hal::digital::OutputPin"><code>OutputPin</code></a>) using HAL-independent <a href="trait.SpiDevice.html" title="trait embedded_hal::spi::SpiDevice"><code>SpiDevice</code></a> implementations such as the ones in <a href="https://crates.io/crates/embedded-hal-bus"><code>embedded-hal-bus</code></a>.</p>
|
||
<p>HALs may additionally implement <a href="trait.SpiDevice.html" title="trait embedded_hal::spi::SpiDevice"><code>SpiDevice</code></a> to <strong>take advantage of hardware CS management</strong>, which may provide some performance
|
||
benefits. (There’s no point in a HAL implementing <a href="trait.SpiDevice.html" title="trait embedded_hal::spi::SpiDevice"><code>SpiDevice</code></a> if the CS management is software-only, this task is better left to
|
||
the HAL-independent implementations).</p>
|
||
<p>HALs <strong>must not</strong> add infrastructure for sharing at the <a href="trait.SpiBus.html" title="trait embedded_hal::spi::SpiBus"><code>SpiBus</code></a> level. User code owning a <a href="trait.SpiBus.html" title="trait embedded_hal::spi::SpiBus"><code>SpiBus</code></a> must have the guarantee
|
||
of exclusive access.</p>
|
||
<h2 id="flushing"><a class="doc-anchor" href="#flushing">§</a>Flushing</h2>
|
||
<p>To improve performance, <a href="trait.SpiBus.html" title="trait embedded_hal::spi::SpiBus"><code>SpiBus</code></a> implementations are allowed to return before the operation is finished, i.e. when the bus is still not
|
||
idle. This allows pipelining SPI transfers with CPU work.</p>
|
||
<p>When calling another method when a previous operation is still in progress, implementations can either wait for the previous operation
|
||
to finish, or enqueue the new one, but they must not return a “busy” error. Users must be able to do multiple method calls in a row
|
||
and have them executed “as if” they were done sequentially, without having to check for “busy” errors.</p>
|
||
<p>When using a <a href="trait.SpiBus.html" title="trait embedded_hal::spi::SpiBus"><code>SpiBus</code></a>, call <a href="trait.SpiBus.html#tymethod.flush" title="method embedded_hal::spi::SpiBus::flush"><code>flush</code></a> to wait for operations to actually finish. Examples of situations
|
||
where this is needed are:</p>
|
||
<ul>
|
||
<li>To synchronize SPI activity and GPIO activity, for example before deasserting a CS pin.</li>
|
||
<li>Before deinitializing the hardware SPI peripheral.</li>
|
||
</ul>
|
||
<p>When using a <a href="trait.SpiDevice.html" title="trait embedded_hal::spi::SpiDevice"><code>SpiDevice</code></a>, you can still call <a href="trait.SpiBus.html#tymethod.flush" title="method embedded_hal::spi::SpiBus::flush"><code>flush</code></a> on the bus within a transaction.
|
||
It’s very rarely needed, because <a href="trait.SpiDevice.html#tymethod.transaction" title="method embedded_hal::spi::SpiDevice::transaction"><code>transaction</code></a> already flushes for you
|
||
before deasserting CS. For example, you may need it to synchronize with GPIOs other than CS, such as DCX pins
|
||
sometimes found in SPI displays.</p>
|
||
<p>For example, for <a href="trait.SpiBus.html#tymethod.write" title="method embedded_hal::spi::SpiBus::write"><code>write</code></a> operations, it is common for hardware SPI peripherals to have a small
|
||
FIFO buffer, usually 1-4 bytes. Software writes data to the FIFO, and the peripheral sends it on MOSI at its own pace,
|
||
at the specified SPI frequency. It is allowed for an implementation of <a href="trait.SpiBus.html#tymethod.write" title="method embedded_hal::spi::SpiBus::write"><code>write</code></a> to return as soon
|
||
as all the data has been written to the FIFO, before it is actually sent. Calling <a href="trait.SpiBus.html#tymethod.flush" title="method embedded_hal::spi::SpiBus::flush"><code>flush</code></a> would
|
||
wait until all the bits have actually been sent, the FIFO is empty, and the bus is idle.</p>
|
||
<p>This still applies to other operations such as <a href="trait.SpiBus.html#tymethod.read" title="method embedded_hal::spi::SpiBus::read"><code>read</code></a> or <a href="trait.SpiBus.html#tymethod.transfer" title="method embedded_hal::spi::SpiBus::transfer"><code>transfer</code></a>. It is less obvious
|
||
why, because these methods can’t return before receiving all the read data. However it’s still technically possible
|
||
for them to return before the bus is idle. For example, assuming SPI mode 0, the last bit is sampled on the first (rising) edge
|
||
of SCK, at which point a method could return, but the second (falling) SCK edge still has to happen before the bus is idle.</p>
|
||
<h2 id="cs-to-clock-delays"><a class="doc-anchor" href="#cs-to-clock-delays">§</a>CS-to-clock delays</h2>
|
||
<p>Many chips require a minimum delay between asserting CS and the first SCK edge, and the last SCK edge and deasserting CS.
|
||
Drivers should <em>NOT</em> use <a href="enum.Operation.html#variant.DelayNs" title="variant embedded_hal::spi::Operation::DelayNs"><code>Operation::DelayNs</code></a> for this, they should instead document that the user should configure the
|
||
delays when creating the <code>SpiDevice</code> instance, same as they have to configure the SPI frequency and mode. This has a few advantages:</p>
|
||
<ul>
|
||
<li>Allows implementations that use hardware-managed CS to program the delay in hardware</li>
|
||
<li>Allows the end user more flexibility. For example, they can choose to not configure any delay if their MCU is slow
|
||
enough to “naturally” do the delay (very common if the delay is in the order of nanoseconds).</li>
|
||
</ul>
|
||
</div></details><h2 id="structs" class="section-header">Structs<a href="#structs" class="anchor">§</a></h2><ul class="item-table"><li><div class="item-name"><a class="struct" href="struct.Mode.html" title="struct embedded_hal::spi::Mode">Mode</a></div><div class="desc docblock-short">SPI mode.</div></li></ul><h2 id="enums" class="section-header">Enums<a href="#enums" class="anchor">§</a></h2><ul class="item-table"><li><div class="item-name"><a class="enum" href="enum.ErrorKind.html" title="enum embedded_hal::spi::ErrorKind">Error<wbr>Kind</a></div><div class="desc docblock-short">SPI error kind.</div></li><li><div class="item-name"><a class="enum" href="enum.Operation.html" title="enum embedded_hal::spi::Operation">Operation</a></div><div class="desc docblock-short">SPI transaction operation.</div></li><li><div class="item-name"><a class="enum" href="enum.Phase.html" title="enum embedded_hal::spi::Phase">Phase</a></div><div class="desc docblock-short">Clock phase.</div></li><li><div class="item-name"><a class="enum" href="enum.Polarity.html" title="enum embedded_hal::spi::Polarity">Polarity</a></div><div class="desc docblock-short">Clock polarity.</div></li></ul><h2 id="constants" class="section-header">Constants<a href="#constants" class="anchor">§</a></h2><ul class="item-table"><li><div class="item-name"><a class="constant" href="constant.MODE_0.html" title="constant embedded_hal::spi::MODE_0">MODE_0</a></div><div class="desc docblock-short">Helper for CPOL = 0, CPHA = 0.</div></li><li><div class="item-name"><a class="constant" href="constant.MODE_1.html" title="constant embedded_hal::spi::MODE_1">MODE_1</a></div><div class="desc docblock-short">Helper for CPOL = 0, CPHA = 1.</div></li><li><div class="item-name"><a class="constant" href="constant.MODE_2.html" title="constant embedded_hal::spi::MODE_2">MODE_2</a></div><div class="desc docblock-short">Helper for CPOL = 1, CPHA = 0.</div></li><li><div class="item-name"><a class="constant" href="constant.MODE_3.html" title="constant embedded_hal::spi::MODE_3">MODE_3</a></div><div class="desc docblock-short">Helper for CPOL = 1, CPHA = 1.</div></li></ul><h2 id="traits" class="section-header">Traits<a href="#traits" class="anchor">§</a></h2><ul class="item-table"><li><div class="item-name"><a class="trait" href="trait.Error.html" title="trait embedded_hal::spi::Error">Error</a></div><div class="desc docblock-short">SPI error.</div></li><li><div class="item-name"><a class="trait" href="trait.ErrorType.html" title="trait embedded_hal::spi::ErrorType">Error<wbr>Type</a></div><div class="desc docblock-short">SPI error type trait.</div></li><li><div class="item-name"><a class="trait" href="trait.SpiBus.html" title="trait embedded_hal::spi::SpiBus">SpiBus</a></div><div class="desc docblock-short">SPI bus.</div></li><li><div class="item-name"><a class="trait" href="trait.SpiDevice.html" title="trait embedded_hal::spi::SpiDevice">SpiDevice</a></div><div class="desc docblock-short">SPI device trait.</div></li></ul></section></div></main></body></html> |