7Semi-SCD4x-CO₂-Temperature-Humidity-Sensor-Module-I2C-Arduino-Library

This Arduino library provides support for the 7Semi-SCD4x (SCD40/SCD41) sensor module over I2C. It enables real-time measurement of CO₂ (ppm), temperature (°C), and humidity (%), and supports both continuous and single-shot measurement modes. The library also includes CRC8 validation and optional data-ready status polling.

Hardware Required

• 7Semi SCD40 or SCD41 sensor module
• Arduino-compatible board
• I2C connection (SDA, SCL)

Getting Started

📦 Manual Installation (ZIP File)

If you have downloaded the library as a ZIP file:

1. Open the Arduino IDE.
2. Go to:
   • IDE 1.x: Sketch > Include Library > Add .ZIP Library…
   • IDE 2.x: Sketch > Include Library > Add .ZIP Library… (same menu)
3. Select the downloaded file: 7semi_scd4x.zip
4. Arduino IDE will automatically install the library into your libraries/ folder.
5. After installation, include the library in your sketch:

#include <7semi_scd4x.h>

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2. Wiring

SCD4x Pin	Arduino Pin
SDA	A4 (Uno)
SCL	A5 (Uno)
VCC	3.3V / 5V
GND	GND

Default I2C address: 0x62