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ESP32 MQTT Tutorial: Publish and Subscribe with Arduino IDE
A complete, broker-agnostic ESP32 MQTT tutorial -- topics, QoS, retained messages, Last Will and Testament, and a working publish/subscribe example with PubSubClient.
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Installing ESP8266 in Arduino IDE: NodeMCU (ESP-12E) Complete Setup Guide for Windows
From driver headaches to a blinking LED — the full Windows walkthrough for getting NodeMCU ESP8266 boards running in Arduino IDE, plus notes for Mac and the bare ESP-01 module.
Raspberry Pi GPIO Pinout: The Ultimate Reference
A comprehensive map of the 40-pin GPIO header on Raspberry Pi 4, 5, and Zero.
ESP32 Pinout Guide: Every GPIO, ADC, PWM, and Restricted Pin Explained
Complete ESP32 pinout guide covering all GPIOs, input-only pins, strapping pins, flash-reserved pins, dual ADC channels, PWM via LEDC, I2C, SPI, UART, and deep sleep wake pins.
Arduino Uno R3 Pinout: Every Pin Explained (Digital, Analog, PWM, Power)
Complete Arduino Uno R3 pinout reference: all 14 digital pins, 6 analog inputs, PWM, UART, SPI, I2C, AREF, and power rails explained with wiring tips and common mistakes.
NodeMCU ESP8266 complete Pinout Guide: GPIO Numbers, D-Pins & Boot Pins Explained
Never confuse D1 with GPIO5 again — plus the D3/D4/D8 boot-mode pins that quietly stop your board from starting.
Ultimate Arduino Mega 2560 Pinout Guide: Complete Power & I/O Reference
Master the Arduino Mega 2560 pinout. Detailed reference for all 54 digital pins, 16 analog inputs, PWM, UARTs, SPI, I2C, interrupts, and power. Includes a printable table and practical wiring tips.
How to Use MQTT with ESP32 and Home Assistant — Complete Beginner Guide
MQTT is the backbone of most smart home systems. This guide shows you how to set up an MQTT broker, connect ESP32, and integrate with Home Assistant from scratch.
Interfacing HC-SR04 Ultrasonic Sensor with Arduino
Measure distance accurately using ultrasonic sound waves and an Arduino Uno — no complex math, no expensive hardware.
Building a Python Flask Server on Raspberry Pi: A Complete Beginner-Friendly Walkthrough
Step-by-step: run a Flask web server on Raspberry Pi to control GPIO pins from any browser — with autostart on boot.
ESP32 vs Arduino: Which Should You Choose in 2026?
ESP32 and Arduino both have their place in electronics. Here's an honest comparison — specs, cost, use cases, and which board wins for your next project.
I2C vs SPI: What's the Difference and When to Use Each
I2C uses 2 wires. SPI uses 4. But the real differences go deeper than that. Here's a practical guide to choosing the right protocol for your Arduino or ESP32 project.