Yevhen Kozachenko 🇺🇦

Posted on Oct 15 • Originally published at ekwoster.dev

🔥 The Untold Secret of ⚡️MicroPython: Build IoT Apps in Minutes with Just 20 Lines of Code!

#micropython #iot #embedded #python

⚡️ The Untold Secret of MicroPython: Build IoT Apps in Minutes with Just 20 Lines of Code!

When it comes to building IoT applications, most developers fear the monster of C++, memory management, and debugging tools from the 90s. But what if I told you that you could write real, production-ready embedded applications in Python, with all the comfort of high-level language features?

Enter MicroPython – a lean, mean implementation of Python 3 specifically designed to run on microcontrollers and constrained devices. It allows you to build embedded software with elegance, conciseness, and clarity. In just minutes, you can create IoT sensors, smart home devices, or data loggers that talk over Wi-Fi, read data, and push it to the web.

In this post, we're going to walk through:

Why MicroPython is a game-changer
Setting up your device in under 5 minutes
A real-world IoT sensor with <20 lines of Python
Pros, cons, and trade-offs

Ready? Let's go!

🚨 Why MicroPython Over Arduino or C++?

Traditional embedded development usually means:

Writing C/C++ for specific hardware
Compiling/flashing cycles that take forever
Complex build systems
Low-level debugging

MicroPython solves this pain by giving you:

A REPL (interactive shell) for live coding on device ⚡️
Built-in support for common modules (I2C, SPI, UART, time, os)
Easy Wi-Fi and HTTP support
Clean syntax and powerful features (coroutines, classes, tuples)
A friendlier learning curve for web/backend developers

If you've written Python, you're 90% of the way there already.

🙌 Hardware You’ll Need (Budget: <$10)

Component	Description	Price
ESP32 board	Microcontroller with Wi-Fi/BLE	~$4
DHT22 sensor	Temperature & humidity sensor	~$2
Jumper wires	Connect everything	~$1
USB cable	To flash the board	-

You can grab a kit on Amazon or AliExpress. Make sure your board is either ESP8266 or ESP32 – both work nicely with MicroPython.

🛠️ Setting Up (In 5 Minutes!)

Install MicroPython on ESP32:

pip install esptool
esptool.py --port /dev/ttyUSB0 erase_flash
esptool.py --chip esp32 --port /dev/ttyUSB0 write_flash -z 0x1000 esp32-*.bin

🔥 Tip: You can get the latest MicroPython firmware for ESP32 from micropython.org/download.

Install a MicroPython IDE (Optional):

Thonny: Super beginner-friendly
uPyCraft (Windows)
rshell, ampy, mpremote for CLI folks

Connect and REPL:

mpremote connect /dev/ttyUSB0

You should see something like this:

MicroPython v1.21.0 on 2024-01; ESP32 module with ESP32
>>>

Boom! You're in.

🌡️ Build an IoT Sensor in 20 Lines of Code

Let’s hook up the ESP32 with a DHT22 sensor. We'll collect temperature & humidity, and send it to a web API.

🧬 Circuit:

DHT22 VCC ➡️ VIN or 3.3V on ESP32
DHT22 GND ➡️ GND
DHT22 DATA ➡️ GPIO 14

🧠 Install Required Packages

MicroPython does not ship with every Python package, but you can install some manually via upip, micropip, or just uploading .py files.

For DHT:

import dht
import machine
import time

sensor = dht.DHT22(machine.Pin(14))

while True:
    sensor.measure()
    t = sensor.temperature()
    h = sensor.humidity()
    print("Temp:", t, "Humidity:", h)
    time.sleep(5)

That’s the whole thing — you now have a functioning IoT device printing real-world sensor readings over a serial monitor.

🌐 Send Data to Web API

Let’s go a step further and push this data to a web server:

import urequests as requests
import network

ssid = 'your-wifi'
password = 'your-password'

wifi = network.WLAN(network.STA_IF)
wifi.active(True)
wifi.connect(ssid, password)

while not wifi.isconnected():
    pass

print("Connected to Wi-Fi!", wifi.ifconfig())

sensor = dht.DHT22(machine.Pin(14))

while True:
    sensor.measure()
    t = sensor.temperature()
    h = sensor.humidity()
    data = {'temp': t, 'humidity': h}
    requests.post("https://webhook.site/your-unique-url", json=data)
    time.sleep(10)

That’s it. No need for C, no need for PlatformIO.

🧠 Tip: Use https://webhook.site for quick testing.

✅ Pros and Gotchas of MicroPython

Pros

Blazing fast development cycle
Great for prototyping & educational purposes
Modern syntax and tooling
Active ecosystem and documentation

Gotchas

Limited memory (often <512KB RAM)
No support for heavy modules (e.g., Pandas, NumPy)
Not as optimized as C++ for performance-critical apps
You may need to write drivers for some peripherals voluntarily

📦 Production Use? When to Consider MicroPython

MicroPython is not just a toy. It’s used in:

Industrial IoT sensors
Educational kits and bootcamps
Smart farming equipment
Rapid prototyping

However, for super real-time systems or ones requiring hard real-time guarantees, use C or Rust. Otherwise, for telemetry, automation, prototyping, or API-driven devices — MicroPython shines.

🧑‍💻 Final Thoughts: Embrace Embedded Python

We’re standing at the intersection of hardware and high-level development. With MicroPython, a backend dev or a frontend dev can now build IoT devices, test quickly, and deploy logic with ease.

You don’t need to be an EE or seasoned embedded programmer to get started. That barrier is now gone.

🚀 In a world of microcontrollers, MicroPython is the scripting hero we didn’t know we needed.

✅ Next Steps

Here’s what you can try next:

Add an OLED screen and display the readings
Collect sensor data and visualize it in Grafana
Send alerts to Telegram when temperature is above a threshold

Let us know what you build in the comments!

Thanks for reading! If this helped you, share it with someone who still thinks Python and memory-constrained hardware can’t be friends. 😉

📣 If you need help prototyping or building your own IoT product fast – we offer research and development services.

DEV Community