Thought I’d share my current project. I’m not an expert by any stretch of the imagination, but I wanted to share working code for anyone that wants to replicate this type of project. The circuitpython project uses the explorer base with a Pico W and BME688 breakout to gather environment data (temp, humidity, and pressure) then display it on screen and save it to a MariaDB database on a Pi5 using PHP. I’m sure there are better, more secure, and tidier ways to do this, but this code works for my purposes.
Here’s the Pimoroni micropython:
# file name: envSensorDisplay.py
from machine import Pin
import time
import utime
import network
import urequests
from breakout_bme68x import BreakoutBME68X
from pimoroni_i2c import PimoroniI2C
from pimoroni import PICO_EXPLORER_I2C_PINS
from picographics import PicoGraphics, DISPLAY_PICO_EXPLORER
# set up the hardware
display = PicoGraphics(display=DISPLAY_PICO_EXPLORER)
i2c = PimoroniI2C(**PICO_EXPLORER_I2C_PINS)
bme = BreakoutBME68X(i2c, address=0x76)
led = Pin("LED", Pin.OUT)
# Create a pen colour to draw with
WHITE = display.create_pen(255, 255, 255)
# Choose a font and switch to the white pen
display.set_pen(0)
display.clear()
display.set_font("bitmap8")
display.set_pen(WHITE)
ssid = 'SSID'
password = 'password'
def connect():
#Connect to WLAN
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
wlan.connect(ssid, password)
while wlan.isconnected() == False:
display.set_pen(0)
display.clear()
display.set_pen(WHITE)
display.text("Waiting for connection...", 0, 0, 1, scale=2)
display.update()
led.on()
utime.sleep(1)
ip = wlan.ifconfig()[0]
display.set_pen(0)
display.clear()
display.set_pen(WHITE)
display.text(f"Connected on {ip}", 0, 0, 140, scale=2)
display.update()
return ip
try:
ip = connect()
except Exception:
display.text(">>> Error or keyboard interrupt", 0, 0, 1, scale=2)
display.update()
machine.reset()
while True:
# read the sensors
temperature, pressure, humidity, gas_resistance, status, gas_index, meas_index = bme.read()
# pressure is in pascals, convert it to the more manageable hPa
pressurehpa = pressure / 100
tempF = temperature*9/5+32
tempFstr = str(tempF)
pressureStr = str(pressurehpa)
humidityStr = str(humidity)
celciusStr = str(temperature)
wlan = network.WLAN(network.STA_IF)
if wlan.status() != 3: #check if connected first
led.off()
display.set_pen(0)
display.clear()
display.set_pen(WHITE)
display.text("Lost connection", 0, 0, scale=2)
display.update()
temp = wlan.status()
connect()
time.sleep(0.25)
# time to update the db and display
URL="URL_to_PHP_API"
DATA={"temperature_celcius":temperature,"temperature_fahrenheit":tempF,"humidity":humidity,"pressure":pressurehpa}
headers = {'X-AIO-Key': 'xxxxxxxxxxxxxxxxxxx',
'Content-Type': 'application/json'}
response = urequests.post(url=URL,json=DATA,headers=headers)
url_response = response.text
display.set_pen(0)
display.clear()
display.set_pen(WHITE)
display.text(url_response, 0, 0, 1, scale=2)
display.text("Fahrenheit = "+tempFstr, 0, 80, scale=2)
display.text("Humidity = "+humidityStr, 0, 100, scale=2)
display.text("Pressure = "+pressureStr, 0, 120, scale=2)
myIP = str(wlan)
stripped_myIP = myIP.strip("CYW43<>STA up")
display.text("IP= "+stripped_myIP, 0, 140, scale=2)
display.update()
response.close()
time.sleep(600)
display.set_pen(0)
display.clear()
# waits for 10 minutes
And here’s the PHP API:
<?php
// Retrieve the raw POST data
$jsonData = file_get_contents('php://input');
// Decode the JSON data into a PHP associative array
$data = json_decode($jsonData, true);
// Assign the decoded data to $_REQUEST
$_REQUEST = $data;
// Access the data and perform operations
//date_default_timezone_set('US/Chicago');
$timestamp = 'NULL';
$temp = $_REQUEST['temperature_celcius'];
$ftemp = $_REQUEST['temperature_fahrenheit'];
$humidity = $_REQUEST['humidity'];
$pressure = $_REQUEST['pressure'];
// Perform further processing or respond to the request
$dbhost = "localhost";
$dbuser = "user";
$dbpass = "password";
$db = "envData";
$conn = mysqli_connect($dbhost, $dbuser, $dbpass, $db);
if (!$conn) {
die("Connection failed: " . mysqli_connect_error());
}
$sql = "INSERT INTO data
VALUES ($timestamp, $temp, $ftemp, $humidity, $pressure)";
if (mysqli_query($conn, $sql)) {
echo "New record created successfully";
} else {
echo "Error: " . $sql . "<br>" . mysqli_error($conn);
}
mysqli_close($conn);
?>
Hope this helps someone looking to do something similar. Any suggestions for improving the code would be very welcome!