7Semi LIS3DH Library

Arduino library for the LIS3DH 3-axis accelerometer (STMicroelectronics).

This library supports both I2C and SPI communication and makes it easy to read:

• Acceleration values (raw and g-units)
• Threshold interrupts (INT1 and INT2)
• ADC channel readings (ADC1 / ADC2 / ADC3)
• Temperature output from internal sensor

The goal of this library is to keep setup simple, while still giving access to advanced LIS3DH features.

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Why use LIS3DH?

LIS3DH is a popular accelerometer used in many applications:

• Motion detection
• Step counting
• Tilt / orientation sensing
• Fall detection
• Vibration monitoring
• Wearables and fitness devices
• Industrial motion monitoring

It supports:

• Very low power mode
• High resolution mode
• Interrupt based detection (no polling needed)

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Features

• I2C + SPI communication

• Acceleration output

• Raw signed 16-bit values

• Converted into g-units (float)

• Sensor configuration

• Scale selection (±2g / ±4g / ±8g / ±16g)

• Output Data Rate selection (1 Hz to 1.6 kHz)

• Interrupt support

• INT1 threshold interrupts

• INT2 threshold interrupts

• Polarity control (active high / low)

• ADC + Temperature

• 3 ADC channels available

• Temperature output via ADC3

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Supported Boards

• Arduino UNO / Mega / Nano
• ESP32 / ESP8266
• Any Arduino-compatible board with I2C or SPI

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Communication Modes

The sensor supports both I2C and SPI.

I2C Mode

• Uses only 2 wires (SDA + SCL)
• Slower than SPI, but simple
• Default address: 0x18
• Alternate address: 0x19 (depends on SA0 pin)

SPI Mode

• Uses 4 wires + CS
• Faster reads, best for higher performance applications
• Requires manual CS pin control
• SPI mode is fixed to SPI_MODE3 for LIS3DH

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Wiring

I2C Wiring

LIS3DH Pin	Arduino Pin
VCC	3.3V / 5V
GND	GND
SDA	SDA
SCL	SCL

If using a 5V board (UNO), confirm that your module has level shifting or supports 5V logic.

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SPI Wiring

LIS3DH Pin	Arduino Pin
VCC	3.3V / 5V
GND	GND
SCL	SCK
SDO	MOSI
SDI	MISO
CS	Any GPIO

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Interrupt Wiring (Optional)

LIS3DH Pin	Arduino Pin
INT1	D2 (example)
INT2	D3 (example)

INT pins are useful for:

• Motion detection
• Wake-up events
• Threshold triggers
• Free-fall events (can be implemented using interrupts)

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Installation

Arduino Library Manager

1. Arduino IDE → Tools → Manage Libraries
2. Search: 7Semi LIS3DH
3. Click install

Manual Install

1. Download repository ZIP
2. Arduino IDE → Sketch → Include Library → Add .ZIP Library
3. Restart IDE

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Basic Usage Flow

Most users follow this pattern:

1. Initialize (I2C or SPI)
2. Configure scale and data rate
3. Read acceleration
4. Optional: use interrupts for event detection
5. Optional: read ADC and temperature

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