tRacket-sensor

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<a href="spl-meter_8h.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a id="l00001" name="l00001"></a><span class="lineno">    1</span> </div>
<div class="line"><a id="l00003" name="l00003"></a><span class="lineno">    3</span><span class="comment">/* noisemeter-device - Firmware for CivicTechTO&#39;s Noisemeter Device</span></div>
<div class="line"><a id="l00004" name="l00004"></a><span class="lineno">    4</span><span class="comment"> * Copyright (C) 2024  Clyne Sullivan, Nick Barnard</span></div>
<div class="line"><a id="l00005" name="l00005"></a><span class="lineno">    5</span><span class="comment"> *</span></div>
<div class="line"><a id="l00006" name="l00006"></a><span class="lineno">    6</span><span class="comment"> * This program is free software: you can redistribute it and/or modify</span></div>
<div class="line"><a id="l00007" name="l00007"></a><span class="lineno">    7</span><span class="comment"> * it under the terms of the GNU General Public License as published by</span></div>
<div class="line"><a id="l00008" name="l00008"></a><span class="lineno">    8</span><span class="comment"> * the Free Software Foundation, either version 3 of the License, or</span></div>
<div class="line"><a id="l00009" name="l00009"></a><span class="lineno">    9</span><span class="comment"> * (at your option) any later version.</span></div>
<div class="line"><a id="l00010" name="l00010"></a><span class="lineno">   10</span><span class="comment"> *</span></div>
<div class="line"><a id="l00011" name="l00011"></a><span class="lineno">   11</span><span class="comment"> * This program is distributed in the hope that it will be useful,</span></div>
<div class="line"><a id="l00012" name="l00012"></a><span class="lineno">   12</span><span class="comment"> * but WITHOUT ANY WARRANTY; without even the implied warranty of</span></div>
<div class="line"><a id="l00013" name="l00013"></a><span class="lineno">   13</span><span class="comment"> * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the</span></div>
<div class="line"><a id="l00014" name="l00014"></a><span class="lineno">   14</span><span class="comment"> * GNU General Public License for more details.</span></div>
<div class="line"><a id="l00015" name="l00015"></a><span class="lineno">   15</span><span class="comment"> *</span></div>
<div class="line"><a id="l00016" name="l00016"></a><span class="lineno">   16</span><span class="comment"> * You should have received a copy of the GNU General Public License</span></div>
<div class="line"><a id="l00017" name="l00017"></a><span class="lineno">   17</span><span class="comment"> * along with this program.  If not, see &lt;https://www.gnu.org/licenses/&gt;.</span></div>
<div class="line"><a id="l00018" name="l00018"></a><span class="lineno">   18</span><span class="comment"> */</span></div>
<div class="line"><a id="l00019" name="l00019"></a><span class="lineno">   19</span><span class="preprocessor">#ifndef SPL_METER_H</span></div>
<div class="line"><a id="l00020" name="l00020"></a><span class="lineno">   20</span><span class="preprocessor">#define SPL_METER_H</span></div>
<div class="line"><a id="l00021" name="l00021"></a><span class="lineno">   21</span> </div>
<div class="line"><a id="l00022" name="l00022"></a><span class="lineno">   22</span><span class="preprocessor">#if defined(USE_MIC_IM64D130A)</span></div>
<div class="line"><a id="l00023" name="l00023"></a><span class="lineno">   23</span><span class="preprocessor">#include &lt;driver/i2s_pdm.h&gt;</span></div>
<div class="line"><a id="l00024" name="l00024"></a><span class="lineno">   24</span><span class="preprocessor">#elif defined(USE_MIC_SPH0645)</span></div>
<div class="line"><a id="l00025" name="l00025"></a><span class="lineno">   25</span><span class="preprocessor">#include &lt;driver/i2s_std.h&gt;</span></div>
<div class="line"><a id="l00026" name="l00026"></a><span class="lineno">   26</span><span class="preprocessor">#endif</span></div>
<div class="line"><a id="l00027" name="l00027"></a><span class="lineno">   27</span> </div>
<div class="line"><a id="l00028" name="l00028"></a><span class="lineno">   28</span><span class="preprocessor">#include &lt;array&gt;</span></div>
<div class="line"><a id="l00029" name="l00029"></a><span class="lineno">   29</span><span class="preprocessor">#include &lt;cstdint&gt;</span></div>
<div class="line"><a id="l00030" name="l00030"></a><span class="lineno">   30</span><span class="preprocessor">#include &lt;optional&gt;</span></div>
<div class="line"><a id="l00031" name="l00031"></a><span class="lineno">   31</span> </div>
<div class="foldopen" id="foldopen00035" data-start="{" data-end="};">
<div class="line"><a id="l00035" name="l00035"></a><span class="lineno"><a class="line" href="classSPLMeter.html">   35</a></span><span class="keyword">class </span><a class="code hl_class" href="classSPLMeter.html">SPLMeter</a></div>
<div class="line"><a id="l00036" name="l00036"></a><span class="lineno">   36</span>{</div>
<div class="line"><a id="l00037" name="l00037"></a><span class="lineno">   37</span><span class="keyword">public</span>:</div>
<div class="line"><a id="l00039" name="l00039"></a><span class="lineno"><a class="line" href="classSPLMeter.html#a32e86c62ca7ca0a689a3746095a70833">   39</a></span>    <span class="keyword">static</span> <span class="keyword">constexpr</span> <span class="keyword">auto</span> <a class="code hl_variable" href="classSPLMeter.html#a32e86c62ca7ca0a689a3746095a70833">SAMPLE_RATE</a> = 48000u;</div>
<div class="line"><a id="l00040" name="l00040"></a><span class="lineno">   40</span> </div>
<div class="line"><a id="l00042" name="l00042"></a><span class="lineno"><a class="line" href="classSPLMeter.html#aa8094a48a43c460a8d9df34a849ed566">   42</a></span>    <span class="keywordtype">void</span> <a class="code hl_function" href="classSPLMeter.html#aa8094a48a43c460a8d9df34a849ed566">initMicrophone</a>() noexcept;</div>
<div class="line"><a id="l00043" name="l00043"></a><span class="lineno">   43</span> </div>
<div class="line"><a id="l00048" name="l00048"></a><span class="lineno"><a class="line" href="classSPLMeter.html#a07a48dbda1a2ef0d7c9baf29a0d31ffd">   48</a></span>    std::optional&lt;<span class="keywordtype">float</span>&gt; <a class="code hl_function" href="classSPLMeter.html#a07a48dbda1a2ef0d7c9baf29a0d31ffd">readMicrophoneData</a>() noexcept;</div>
<div class="line"><a id="l00049" name="l00049"></a><span class="lineno">   49</span> </div>
<div class="line"><a id="l00050" name="l00050"></a><span class="lineno">   50</span>private:</div>
<div class="line"><a id="l00052" name="l00052"></a><span class="lineno"><a class="line" href="classSPLMeter.html#a560467629e9cd5043102c06f88c8870a">   52</a></span>    static constexpr auto <a class="code hl_variable" href="classSPLMeter.html#a560467629e9cd5043102c06f88c8870a">SAMPLES_SHORT</a> = <a class="code hl_variable" href="classSPLMeter.html#a32e86c62ca7ca0a689a3746095a70833">SAMPLE_RATE</a> / 16u;</div>
<div class="line"><a id="l00053" name="l00053"></a><span class="lineno">   53</span> </div>
<div class="line"><a id="l00055" name="l00055"></a><span class="lineno">   55</span>    alignas(4)</div>
<div class="line"><a id="l00056" name="l00056"></a><span class="lineno"><a class="line" href="classSPLMeter.html#aa26165ecce065d5b521522b646cf9012">   56</a></span>    std::array&lt;<span class="keywordtype">float</span>, <a class="code hl_variable" href="classSPLMeter.html#a560467629e9cd5043102c06f88c8870a">SAMPLES_SHORT</a>&gt; <a class="code hl_variable" href="classSPLMeter.html#aa26165ecce065d5b521522b646cf9012">samples</a>;</div>
<div class="line"><a id="l00057" name="l00057"></a><span class="lineno">   57</span> </div>
<div class="line"><a id="l00059" name="l00059"></a><span class="lineno"><a class="line" href="classSPLMeter.html#aa2e3b5b980830da60d2ab10e55ff4ba6">   59</a></span>    <span class="keywordtype">unsigned</span> <a class="code hl_variable" href="classSPLMeter.html#aa2e3b5b980830da60d2ab10e55ff4ba6">Leq_samples</a> = 0;</div>
<div class="line"><a id="l00061" name="l00061"></a><span class="lineno"><a class="line" href="classSPLMeter.html#aa8c155bc251f8ce89f703c49fcb6ba0b">   61</a></span>    <span class="keywordtype">float</span> <a class="code hl_variable" href="classSPLMeter.html#aa8c155bc251f8ce89f703c49fcb6ba0b">Leq_sum_sqr</a> = 0;</div>
<div class="line"><a id="l00062" name="l00062"></a><span class="lineno">   62</span> </div>
<div class="line"><a id="l00063" name="l00063"></a><span class="lineno">   63</span>    i2s_chan_handle_t i2s_handle;</div>
<div class="line"><a id="l00064" name="l00064"></a><span class="lineno">   64</span> </div>
<div class="line"><a id="l00066" name="l00066"></a><span class="lineno"><a class="line" href="classSPLMeter.html#ac5ad129ef889803af633b9a2c632c11f">   66</a></span>    <span class="keywordtype">size_t</span> <a class="code hl_function" href="classSPLMeter.html#ac5ad129ef889803af633b9a2c632c11f">i2sRead</a>() noexcept;</div>
<div class="line"><a id="l00067" name="l00067"></a><span class="lineno">   67</span>};</div>
</div>
<div class="line"><a id="l00068" name="l00068"></a><span class="lineno">   68</span> </div>
<div class="line"><a id="l00069" name="l00069"></a><span class="lineno">   69</span><span class="preprocessor">#endif </span><span class="comment">// SPL_METER_H</span></div>
<div class="line"><a id="l00070" name="l00070"></a><span class="lineno">   70</span> </div>
<div class="ttc" id="aclassSPLMeter_html"><div class="ttname"><a href="classSPLMeter.html">SPLMeter</a></div><div class="ttdoc">Provides a minimal interface for reading decibel levels from the microphone.</div><div class="ttdef"><b>Definition</b> <a href="spl-meter_8h_source.html#l00035">spl-meter.h:36</a></div></div>
<div class="ttc" id="aclassSPLMeter_html_a07a48dbda1a2ef0d7c9baf29a0d31ffd"><div class="ttname"><a href="classSPLMeter.html#a07a48dbda1a2ef0d7c9baf29a0d31ffd">SPLMeter::readMicrophoneData</a></div><div class="ttdeci">std::optional&lt; float &gt; readMicrophoneData() noexcept</div><div class="ttdoc">Samples data from the microphone, potentially returning a new dB reading.</div></div>
<div class="ttc" id="aclassSPLMeter_html_a32e86c62ca7ca0a689a3746095a70833"><div class="ttname"><a href="classSPLMeter.html#a32e86c62ca7ca0a689a3746095a70833">SPLMeter::SAMPLE_RATE</a></div><div class="ttdeci">static constexpr auto SAMPLE_RATE</div><div class="ttdoc">Sampling rate to run the microphone at, in Hertz.</div><div class="ttdef"><b>Definition</b> <a href="spl-meter_8h_source.html#l00039">spl-meter.h:39</a></div></div>
<div class="ttc" id="aclassSPLMeter_html_a560467629e9cd5043102c06f88c8870a"><div class="ttname"><a href="classSPLMeter.html#a560467629e9cd5043102c06f88c8870a">SPLMeter::SAMPLES_SHORT</a></div><div class="ttdeci">static constexpr auto SAMPLES_SHORT</div><div class="ttdoc">The number of samples to keep in the sample buffer.</div><div class="ttdef"><b>Definition</b> <a href="spl-meter_8h_source.html#l00052">spl-meter.h:52</a></div></div>
<div class="ttc" id="aclassSPLMeter_html_aa26165ecce065d5b521522b646cf9012"><div class="ttname"><a href="classSPLMeter.html#aa26165ecce065d5b521522b646cf9012">SPLMeter::samples</a></div><div class="ttdeci">std::array&lt; float, SAMPLES_SHORT &gt; samples</div><div class="ttdoc">Buffer to store microphone samples in for reading and processing.</div><div class="ttdef"><b>Definition</b> <a href="spl-meter_8h_source.html#l00056">spl-meter.h:56</a></div></div>
<div class="ttc" id="aclassSPLMeter_html_aa2e3b5b980830da60d2ab10e55ff4ba6"><div class="ttname"><a href="classSPLMeter.html#aa2e3b5b980830da60d2ab10e55ff4ba6">SPLMeter::Leq_samples</a></div><div class="ttdeci">unsigned Leq_samples</div><div class="ttdoc">Number of samples included in Leq_sum_sqr accumulation.</div><div class="ttdef"><b>Definition</b> <a href="spl-meter_8h_source.html#l00059">spl-meter.h:59</a></div></div>
<div class="ttc" id="aclassSPLMeter_html_aa8094a48a43c460a8d9df34a849ed566"><div class="ttname"><a href="classSPLMeter.html#aa8094a48a43c460a8d9df34a849ed566">SPLMeter::initMicrophone</a></div><div class="ttdeci">void initMicrophone() noexcept</div><div class="ttdoc">Prepares I2S Driver and microphone hardware.</div></div>
<div class="ttc" id="aclassSPLMeter_html_aa8c155bc251f8ce89f703c49fcb6ba0b"><div class="ttname"><a href="classSPLMeter.html#aa8c155bc251f8ce89f703c49fcb6ba0b">SPLMeter::Leq_sum_sqr</a></div><div class="ttdeci">float Leq_sum_sqr</div><div class="ttdoc">Accumulation of sums of squares for decibel calculation.</div><div class="ttdef"><b>Definition</b> <a href="spl-meter_8h_source.html#l00061">spl-meter.h:61</a></div></div>
<div class="ttc" id="aclassSPLMeter_html_ac5ad129ef889803af633b9a2c632c11f"><div class="ttname"><a href="classSPLMeter.html#ac5ad129ef889803af633b9a2c632c11f">SPLMeter::i2sRead</a></div><div class="ttdeci">size_t i2sRead() noexcept</div><div class="ttdoc">Reads enough samples from the microphone to fill the samples buffer.</div></div>
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