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Added luminosity sensor, more acurate temperature end debounced rainfall meter

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marcel
2025-01-14 17:19:12 +01:00
parent aaec2a02ad
commit 92956c2707
7 changed files with 259 additions and 39 deletions
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@@ -5,7 +5,7 @@
<meta name="generator" content="pandoc" />
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes" />
<meta name="author" content="M.T. Konstapel" />
<meta name="dcterms.date" content="2024-05-02" />
<meta name="dcterms.date" content="2025-01-14" />
<title>Weather station</title>
<link rel="stylesheet" href="./css/mvp.css" />
<style type="text/css">
@@ -56,6 +56,8 @@
<li><a href="#problems-i-encounter-after-four-months-of-use"
id="toc-problems-i-encounter-after-four-months-of-use">Problems
I encounter after four months of use</a></li>
<li><a href="#additions"
id="toc-additions">Additions</a></li>
<li><a href="#software-dependencies"
id="toc-software-dependencies">Software
dependencies</a></li>
@@ -78,7 +80,7 @@
<h1 class="title">Weather station</h1>
<p class="subtitle">with ModBus RTU interface</p>
<p class="author">M.T. Konstapel</p>
<p class="date">2024-05-02</p>
<p class="date">2025-01-14</p>
<p><a href="./weather_station.pdf"><i>PDF version</i></a></p>
</header>
<main>
@@ -873,6 +875,7 @@ Address : 14</code></pre>
src="./images/weather_station_schematic.svg" alt="Schematic" /></a></p>
<h1 id="problems-i-encounter-after-four-months-of-use">Problems I
encounter after four months of use</h1>
<h2 id="humidity-sensor">Humidity sensor</h2>
<p>The Si7021 humidity sensor is not made for outdoor use. The datasheet
is clear about that. But a lot of people use this cheap sensor for
weather stations anyway. So I choose this sensor for my design. But that
@@ -894,6 +897,88 @@ price: it is ten times more expensive than the Si7021.</p>
<p>The sensor can be controlled via the I2C bus, so implementing the new
sensor in the firmware was very easy. From version 0.3.0 onward, this
sensor is used. The Si7021 is removed from the code.</p>
<h2 id="pressure-sensor">Pressure sensor</h2>
<p>After a year the BMP280 pressure sensor started to give odd pressure
values. The pressure was around 700hPa and followed the temperature
curve. The temperature sensor still worked fine. After replacing the
BMP280 the barometric values returned to normal. I suspect that it
malfunctioned because of the perpetual fog we had for about two months.
The sensor was mounted in the Garni RS1 Passive Radiation Shield. Rain
could not enter the shield, but fog could.</p>
<h1 id="additions">Additions</h1>
<h2 id="luminosity-sensor">Luminosity sensor</h2>
<p>From version 0.3.1 onward, the weather station has an ambient light
sensor. It is an SEN0562 from DFRobot and it outputs the light intensity
in Lux. It is a 5 Volt only device, so it should be connected to the 5
Volt I2C bus.</p>
<figure>
<img
src="./images/dfrobot-gravity-ip68-waterproof-ambient-light-sensor-1-65535lx-i2c.png"
alt="The SEN0562 ambient light sensor" />
<figcaption aria-hidden="true">The SEN0562 ambient light
sensor</figcaption>
</figure>
<figure>
<img
src="./images/dfrobot-gravity-ip68-waterproof-ambient-light-sensor-wiring.png"
alt="Connection of the I2C bus" />
<figcaption aria-hidden="true">Connection of the I2C bus</figcaption>
</figure>
<p>The sensor has the following specifications:</p>
<ul>
<li>Supply Voltage: 5V</li>
<li>Operating Current: 1µA</li>
<li>Detection Range: 1 - 65535lx</li>
<li>Accuracy: 1.2lx</li>
<li>Communication Mode: I2C</li>
<li>Operating Temperature: -40 to 85°C/-40 to 185℉</li>
<li>Waterproof Rating: IP68</li>
<li>Thread Length: 10mm</li>
<li>Cutout Size: 26mm</li>
<li>Wrench Size: 31mm</li>
<li>Cable Diameter: 3mm</li>
<li>Wire Length: 1m</li>
</ul>
<p>Sample code:</p>
<pre><code>#include &quot;Wire.h&quot;
#define address 0x23 //I2C address 0x23
void setup()
{
Serial.begin(9600);
Wire.begin();
}
uint8_t buf[4] = {0};
uint16_t data, data1;
float Lux;
void loop()
{
readReg(0x10, buf, 2); //Register address 0x10
data = buf[0] &lt;&lt; 8 | buf[1];
Lux = (((float)data )/1.2);
Serial.print(&quot;LUX:&quot;);
Serial.print(Lux);
Serial.print(&quot;lx&quot;);
Serial.print(&quot;\n&quot;);
delay(500);
}
uint8_t readReg(uint8_t reg, const void* pBuf, size_t size)
{
if (pBuf == NULL) {
Serial.println(&quot;pBuf ERROR!! : null pointer&quot;);
}
uint8_t * _pBuf = (uint8_t *)pBuf;
Wire.beginTransmission(address);
Wire.write(&amp;reg, 1);
if ( Wire.endTransmission() != 0) {
return 0;
}
delay(20);
Wire.requestFrom(address, (uint8_t) size);
for (uint16_t i = 0; i &lt; size; i++) {
_pBuf[i] = Wire.read();
}
return size;
}</code></pre>
<!---
# Bill of materials
@@ -914,7 +999,7 @@ sensor is used. The Si7021 is removed from the code.</p>
</ul>
<p>Libraries are included with the source code of this project</p>
<h1 id="license">License</h1>
<p>Copyright (C) 2023, 2024 M.T. Konstapel</p>
<p>Copyright (C) 2023-2025 M.T. Konstapel</p>
<p><a
href="https://meezenest.nl/mees/">https://meezenest.nl/mees/</a></p>
<p>The software is published as open-source software (GPL). The hardware
@@ -932,7 +1017,7 @@ option) any later version.</p>
</main>
<footer>
<p>&copy;
2024-05-02
2025-01-14
M.T. Konstapel
<a href="https://meezenest.nl/mees/">https://meezenest.nl/mees/</a>
</p><p>This work is licensed under a <a rel="license" href="http://creativecommons.org/licenses/by-sa/4.0/">Creative Commons Attribution-ShareAlike 4.0 International License</a>.