Raspberry Pi Pico 2W + Mobile App: Build Your Own Smart Wi-Fi Thermometer!

Have you ever wanted to easily monitor the temperature in every room of your house? The good news is that you can do it effortlessly for under ten dollars!

Supplies

Raspberry PI Pico 2W: https://www.raspberrypi.com/products/raspberry-pi-pico-2/?variant=pico-2-w

Temperature Sensor DS19B20: https://amzn.to/3ZvjAJz

Connect Temperature Sensor to PICO

Connect DS18B20 to the Raspberry PI Pico according to schema using a resistor between Red and Yellow wire.

Set Up Visual Studio Code

Install Visual Studio Code
Open Settings -> Extensions
Install Python, Raspberry PI Pico, MicroPico

Connect to the Raspberry PI

Open View -> Command Pallete
Search for MicroPico: Connect
Create a file main.py
Add a line print("Hello") to the main.py
When Pico connects, run All Commands -> Upload Project
Press "Run"

Clone a Raspberry PI Pico Framework

Run:

git init

git submodule add https://github.com/Nerdy-Things/itk_pico.git

Broadcast Temperature to the Wi-Fi Network

Replace code in the main.py with:

from itk_pico.temperature import TemperatureSensor

from itk_pico.wifi import WiFi

from itk_pico.udp import Udp

from itk_pico.ip_utils import get_broadcast_address

from time import sleep

import json

UDP_PORT = 5468

temperature_sensor = TemperatureSensor(15)

wifi = WiFi()

udp = Udp(UDP_PORT)

wifi.connect("itkacher", "itkacher")

while True:

wifi.try_reconnect_if_lost()

temperature = temperature_sensor.get_temperature()

broadcast_ip_address = get_broadcast_address(wifi.get_ip_address(), wifi.get_subnet_mask())

message_dict = {"name": "Kitchen", "temperature": temperature}

message = json.dumps(message_dict)

udp.send(message, broadcast_ip_address, UDP_PORT)

sleep(10)

Upload the project to the Raspberry PI Pico 2W and press Run

Clone a Cross-platform Application

git clone https://github.com/Nerdy-Things/raspberry-pi-pico-thermo-sensor-cross-platform.git

Run the Application

To run a desktop application:

cd raspberry-pi-pico-thermo-sensor-cross-platform

cd kotlin-multiplatform

./gradlew run

To run an Android application:

Open the raspberry-pi-pico-thermo-sensor-cross-platform/kotlin-multiplatform folder in Android Studio. Press Run.

To run an iPhone application:

Open the iosApp/iosApp.xcodeproj file in xCode. Press Run.