Guides
Pinouts. Tutorials. Answers.
Chip and board pinouts, plus sensor and module reference guides: real GPIO tables, real specifications, and working code for each one.
Reference
Servo Tester
A small box with a knob that moves a servo without any code: what the modes do, what to look for when you buy one, and how to centre a servo before you fit the arm.
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Reference
The Ultimate Guide to the SHT Sensor Series
Sensirion's SHT2x/3x/4x family are factory-calibrated I2C temperature and humidity sensors with low drift and fast response. This guide compares the three series, covers wiring an SHT31 to an ESP32, and helps pick the right model for accuracy, power budget or outdoor use.
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Guide
ESP32-C6-WROOM-1 Pinout
The complete pin reference for the ESP32-C6-WROOM-1 module: Wi-Fi 6, Bluetooth LE and 802.15.4 (Thread and Zigbee) on one chip, plus the exact pins you can safely reuse.
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Reference
ESP8266 Pinout
The complete pin reference for the ESP8266 NodeMCU board: all 30 pins with GPIO numbers, boot pins, flash pins, power and programming.
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Reference
SSD1306 OLED Display
A tiny, self-illuminating I2C display for turning a headless ESP32 project into something readable at a glance. Covers the SSD1306 vs SH1106 offset trap, how the page-based framebuffer works, and avoiding burn-in.
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Reference
INA219 / INA226 Voltage, Current and Power Sensor Complete Guide
The INA219 and INA226 measure voltage, current and power on a low-voltage DC bus over I2C, using a shunt resistor and Ohm's law, not the mains-AC energy-meter ICs this site already covers. This guide covers both chips' real specs, wiring one to an ESP32, and which to pick for a battery or power-budget project.
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Reference
MG996R Servo
The standard-size, high-torque metal gear servo: specifications, the position versus 360 degree confusion, wiring and the control signal, how to power it without brownouts, and how to drive it from an ESP32-S3.
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