jdillenburg-esphome/components/adxl345

ADXL345 Component for ESPHome

This is a custom component for ESPHome that interfaces with the ADXL345 3-axis accelerometer.

Features

• Supports all standard I2C configuration options including multiple I2C buses
• Configurable measurement range (2G, 4G, 8G, 16G)
• Provides raw acceleration values for X, Y, and Z axes
• Calculates off-vertical angle (useful for bed/chair position tracking)
• Calculates jitter (total movement across all axes)
• Full Home Assistant integration with proper device classes and units

Installation

1. Create a components directory in your ESPHome configuration directory if it doesn't exist
2. Create an adxl345 directory inside the components directory
3. Copy the following files into the adxl345 directory:
   • __init__.py
   • adxl345.h
   • adxl345.cpp
   • sensor.py

Dependencies

This component requires the following libraries:

• Wire
• SPI
• Adafruit BusIO
• Adafruit Unified Sensor
• Adafruit ADXL345

Add these to your ESPHome configuration:

libraries:
  - "Wire"
  - "SPI"
  - "Adafruit BusIO"
  - "Adafruit Unified Sensor"
  - "Adafruit ADXL345"

Usage

Basic Configuration

# Define component and sensors for accel_x, accel_y and accel_z
adxl345:
  - id: my_adxl345
    address: 0x53
    update_interval: 100ms
    accel_x:
      name: "Acceleration X"
    accel_y:
      name: "Acceleration Y"
    accel_z:
      name: "Acceleration Z"

Advanced Configuration

# Define I2C bus
i2c:
  sda: GPIO21
  scl: GPIO22
  frequency: 400kHz

# Define component with all options
adxl345:
  - id: my_adxl345
    address: 0x53
    update_interval: 100ms
    range: 4G  # Options: 2G, 4G, 8G, 16G
    accel_x:
      name: "Acceleration X"
      filters:
        - median:
            window_size: 5
            send_every: 5
            send_first_at: 1
    accel_y:
      name: "Acceleration Y"
    accel_z:
      name: "Acceleration Z"
    off_vertical:
      name: "Tilt Angle"
      filters:
        - sliding_window_moving_average:
            window_size: 10
            send_every: 5
    jitter:
      name: "Movement Detection"
      filters:
        - threshold:
            above: 10.0
            then: ON
            below: 2.0
            then: OFF

Available Sensors

Sensor	Description	Unit
accel_x	Raw X-axis acceleration	m/s²
accel_y	Raw Y-axis acceleration	m/s²
accel_z	Raw Z-axis acceleration	m/s²
off_vertical	Maximum angle from vertical (derived from pitch and roll)	degrees
jitter	Sum of absolute accelerations across all axes (movement detection)	m/s²

Example Use Cases

• Bed/chair incline monitoring
• Movement detection
• Vibration monitoring
• Orientation sensing