ESP32 technical tutorials
Learn to program robust firmware for factory environments with ready-to-compile code examples.
MQTT with TLS on the ESP32: validate the broker certificate and stop using setInsecure
The setInsecure() example encrypts but accepts any server. Your own CA, Mosquitto on port 8883, NTP time, heap and the negative tests that prove validation works.
LoRa on the ESP32: long-range point-to-point communication, without LoRaWAN
Two Heltec WiFi LoRa 32 V2 boards talking across hundreds of meters: SF, bandwidth and time on air, what we measured in the lab, the antenna, crystal and ACK traps, and packet loss by sequence number.
How to build an AI copilot without paying for an API: this site's architecture
This site's copilot does not call a paid AI API—it runs isolated and authenticated by login. The two-process architecture and the bug that almost invented an answer.
Using an AI assistant to program the ESP32: the workflow that works
The assistant writes plausible code without seeing the board powered on. Learn the workflow, and why pasting real output beats describing errors.
A language model running on the ESP32-S3
A transformer performs inference inside the microcontroller, without the cloud: why memory is the wall, where speed comes from and how to reproduce it.
Production counter with ESP32 without losing pulses
The debounce copied from a button tutorial becomes a production ceiling: 50 ms limits the line to 1,200 pieces per minute. IRAM interrupt and isolated input.
How NAT works on an ESP32: Wi-Fi routing and repeater
NAPT does not work in Arduino Core: its lwIP lacks IP_FORWARD. Learn the ESP-IDF sdkconfig, DNS propagation through DHCP and a measured repeater running in practice.
ESP32-S3 with PlatformIO from scratch
Configure the ESP32-S3 in PlatformIO: octal PSRAM with qio_opi, a silent serial monitor caused by USB-CDC and a partition table for 16 MB of flash.
MQTT automatic reconnection without blocking the loop
The while loop found in every tutorial freezes the firmware when the broker goes down. Learn the millis() guard pattern, separate schedules and rc codes.
Modbus RTU over RS-485 on the ESP32
Read Modbus RTU registers on the ESP32 without a library: DE/RE control, CRC16, the 3.5-character silence between frames and 120-ohm termination.
How to create an embedded Wi-Fi portal on the ESP32
A portal that a technician opens on a phone to configure Wi-Fi without a cable: network scanning, NVS storage and a connection test that does not block the HTTP response.
OTA (Over-The-Air) updates on the ESP32
Two partitions, otadata and the pending-verification state: how to update firmware over the network without turning a bug into a service visit.
Watchdog Timer and automatic failure recovery
Restarting by itself is easy. The hard part is restarting only when needed, knowing why it happened and avoiding a loop—with Task WDT, reset reason and backoff.
Local SPIFFS/LittleFS buffer when the network goes down
Saving data while the network is down is the easy part. The hard part is not destroying flash, knowing the time and not flooding the broker when the network returns.
ESP32 sending data to SCADA and MES
SCADA does not want your JSON: it wants tags. Topic modeling, data quality, heartbeat and why the gateway timestamp is not enough.
Motor temperature and vibration monitoring with ESP32
Predictive maintenance node with MPU6050 and a Type K thermocouple: vibration RMS, MQTT telemetry and a mechanical trend becoming a useful SCADA alarm.
First steps with ESP32-C3 and 1.44" LCD
From a blank computer to the first text on a Spotpear ESP32-C3 display: install Python and PlatformIO, save the factory firmware, compile and flash.
Program the ESP32 in VS Code with PlatformIO
From zero to a blinking LED: install, open the project, compile and flash the board using the interface buttons, without typing a command.
What is PlatformIO (PIO) and why did it become the ESP32 standard?
PlatformIO is neither an editor nor a compiler: it builds the entire environment from a text file. Learn the four layers and what platformio.ini does.
Can an ESP32 use public AI APIs? Yes—and where each piece works
A 28.9M-parameter language model generates text inside an ESP32-S3 at 9.5 tokens per second. The correction, and where each piece works.
ESP32 publishing data to Mosquitto
Step by step to connect an ESP32 to an Eclipse Mosquitto MQTT broker, handling authentication and JSON telemetry format.