ESP32 Project #9 Building Weather Station with BMP180

Hi, I’m back. On this project I’ll create a web server which display readings from BMP180 sensor. The BMP180 sensor measures temperature, humidity, and pressure. Let’s start!

Parts and Component

I’ll need

  • Breadboard
  • Jumper wires
  • BMP180 sensor
  • Arduino IDE
  • USB Cable

BMP180 Sensor

There are 4 pins on the sensor which will be connected to the ESP32. Follow the pins below:

  • VCC — VIN
  • SDA — GPIO 21
  • SCL — GPIO 22
Wiring

HTML

I will create a table with HTML. The code looks like this.

<table>
<tr>
<th>MEASUREMENT</th>
<th>VALUE</th>
</tr>
<tr>
<td>Temp. Celsius</td>
<td>--- *C</td>
</tr>
<tr>
<td>Temp. Fahrenheit</td>
<td>--- *F</td>
</tr>
<tr>
<td>Pressure</td>
<td>--- hPa</td>
</tr>
<tr>
<td>Approx. Altitude</td>
<td>--- meters</td></tr>
<tr>
<td>Humidity</td>
<td>--- %</td>
</tr>
</table>
  • <th> table header
  • <td> table data

CSS

The table looks so so. Let’s style it with CSS.

<!DOCTYPE html>
<html>
<head>
<style>
#weather {
font-family: Trebuchet MS, sans-serif;
border-collapse: collapse;
width: 100%;
}
#weather td, #customers th {
border: 1px solid #ddd;
padding: 8px;
}
#weather tr:nth-child(even){background-color: #f2f2f2;}#weather tr:hover {background-color: #ddd;}#weather th {
padding-top: 12px;
padding-bottom: 12px;
text-align: center;
background-color: #FF9ABB;
color: black;
}
</style>
</head>
<body>
<table id='weather'>
<tr>
<th>MEASUREMENT</th>
<th>VALUE</th>
</tr>
<tr>
<td>Temp. Celsius</td>
<td>--- *C</td>
</tr>
<tr>
<td>Temp. Fahrenheit</td>
<td>--- *F</td>
</tr>
<tr>
<td>Pressure</td>
<td>--- hPa</td>
</tr>
<tr>
<td>Approx. Altitude</td>
<td>--- meters</td></tr>
<tr>
<td>Humidity</td>
<td>--- %</td>
</tr>
</table>
</body>
</html>

Web Server

Based on previous project, I already posted about building a web server.

/*********
Rui Santos
Complete project details at https://randomnerdtutorials.com
*********/
// Load Wi-Fi library
#include <WiFi.h>
#include <Wire.h>
#include <Adafruit_BMP085.h>
Adafruit_BMP085 bmp;// Replace with your network credentials
const char* ssid = "FAMILY";
const char* password = "********";
// Set web server port number to 80
WiFiServer server(80);
// Variable to store the HTTP request
String header;
// Current time
unsigned long currentTime = millis();
// Previous time
unsigned long previousTime = 0;
// Define timeout time in milliseconds (example: 2000ms = 2s)
const long timeoutTime = 2000;
void setup() {
Serial.begin(115200);
bool status;
// default settings
// (you can also pass in a Wire library object like &Wire2)
//status = bmp.begin();
if (!bmp.begin(0x76)) {
Serial.println("Could not find a valid BME280 sensor, check wiring!");
while (1);
}
// Connect to Wi-Fi network with SSID and password
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
// Print local IP address and start web server
Serial.println("");
Serial.println("WiFi connected.");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
server.begin();
}
void loop(){
WiFiClient client = server.available(); // Listen for incoming clients
if (client) { // If a new client connects,
currentTime = millis();
previousTime = currentTime;
Serial.println("New Client."); // print a message out in the serial port
String currentLine = ""; // make a String to hold incoming data from the client
while (client.connected() && currentTime - previousTime <= timeoutTime) { // loop while the client's connected
currentTime = millis();
if (client.available()) { // if there's bytes to read from the client,
char c = client.read(); // read a byte, then
Serial.write(c); // print it out the serial monitor
header += c;
if (c == '\n') { // if the byte is a newline character
// if the current line is blank, you got two newline characters in a row.
// that's the end of the client HTTP request, so send a response:
if (currentLine.length() == 0) {
// HTTP headers always start with a response code (e.g. HTTP/1.1 200 OK)
// and a content-type so the client knows what's coming, then a blank line:
client.println("HTTP/1.1 200 OK");
client.println("Content-type:text/html");
client.println("Connection: close");
client.println();

// Display the HTML web page
client.println("<!DOCTYPE html><html>");
client.println("<head><meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">");
client.println("<link rel=\"icon\" href=\"data:,\">");
// CSS to style the table
client.println("<style>#weather {font-family: Trebuchet MS, sans-serif;border-collapse: collapse;width: 100%;}");
client.println("#weather td, #customers th {border: 1px solid #ddd;padding: 8px;}");
client.println("#weather tr:nth-child(even){background-color: #f2f2f2;}");
client.println("#weather tr:hover {background-color: #ddd;}");
client.println("#weather th {padding-top: 12px;padding-bottom: 12px;text-align: center;background-color: #FF9ABB;color: black;}");
client.println("body { text-align: center; font-family: \"Trebuchet MS\", Arial;}");
client.println(".sensor { color:black; font-weight: bold; background-color: white; padding: 1px; }");

// Web Page Heading
client.println("</style></head><body><h1>ESP32 with BMP180</h1>");
client.println("<table id='weather'><tr><th>MEASUREMENT</th><th>VALUE</th></tr>");
client.println("<tr><td>Temp. Celsius</td><td><span class=\"sensor\">");
client.println(bmp.readTemperature());
client.println(" *C</span></td></tr>");
client.println("<tr><td>Temp. Fahrenheit</td><td><span class=\"sensor\">");
client.println(1.8 * bmp.readTemperature() + 32);
client.println(" *F</span></td></tr>");
client.println("<tr><td>Pressure</td><td><span class=\"sensor\">");
client.println(bmp.readPressure() / 100.0F);
client.println(" hPa</span></td></tr>");
client.println("<tr><td>Approx. Altitude</td><td><span class=\"sensor\">");
client.println(bmp.readAltitude());
client.println(" m</span></td></tr>");
client.println("<tr><td>Sea Level Pressure</td><td><span class=\"sensor\">");
client.println(bmp.readSealevelPressure());
client.println(" %</span></td></tr>");
client.println("</body></html>");

// The HTTP response ends with another blank line
client.println();
// Break out of the while loop
break;
} else { // if you got a newline, then clear currentLine
currentLine = "";
}
} else if (c != '\r') { // if you got anything else but a carriage return character,
currentLine += c; // add it to the end of the currentLine
}
}
}
// Clear the header variable
header = "";
// Close the connection
client.stop();
Serial.println("Client disconnected.");
Serial.println("");
}
}
Weather Station with ESP32 & BMP180
Weather Station with ESP32 & BMP180

Final say

I’ve made a weather station with ESP32 and BMP180 on a web server. I’ve also tried to style the web using CSS following the tutorial from randomnerdtutorials. Hope this project can help and stay tune for the next projects!