Connecting a KX132 Triple Axis Accelerometer to an ESP32 board example

In this article we look at one of 2 similar Triple-axis Magnetometer that I recently purchased, the KX132 Triple Axis Accelerometer, and connect it to an ESP32

Sensor Information

The KX132 is a digital accelerometer from Kionix.

The KX132 is a low-power, 16-bit resolution three-axis accelerometer with four user-selectable acceleration measurement ranges of ±2g/4g/8g/16g and has up to a 10kHz (max) output data rate making it ideal for a wide range of acceleration measurements as well as high-speed applications such as vibration and tap sensing.

The KX132 includes a host of features including Freefall detection, Directional Tap™ and Double-Tap™ detection, tilt orientation detection and more.

The Qwiic KX132 can interface with controllers using both I2C and SPI at high speeds so you can use it in an existing Qwiic/I2C chain or on a SPI bus.

Features

Measurement Range: ±2g, ±4g, ±8g, ±16g (User Selectable)
High Resolution (8 or 16-bit)
User-Configurable Output Data Rate (ODR) up to 25600Hz
User-Configurable 3-stage Advanced Data Path featuring low-pass filter, low-pass/high-pass filter, and RMS calculation engine
Wide range of built-in sensing functions

• Free Fall
• Directional-Tap™ / Double-Tap™
• Device Orientation & Activity Algorithms

Low Noise: 130µg/√Hz (varies based on ODR, power mode & other settings)
High-Resolution Wake-Up & Back-to-Sleep Detection with a configurable threshold as low as 3.9mg
512-byte FIFO buffer that continues recording data while being read
Selectable Low-Power or High-Performance operating modes
Low Power with Integrated Voltage Regulator

• High Performance Operating Current Consumption (400Hz ODR + Wake-Up Detection): 148µA
• Low Power Operating Current Consumption (0.781Hz ODR + Wake-Up Detection): 0.53µA
• Standby Current Consumption: 0.5µA

Self-Test Functionality
Digital I2C up to 3.4MHz and Digital SPI up to 10MHz
2x Qwiic Connectors
SPI available on PTH Header Pins
I2C Address: 0x1E (0x1F can be used as an alternate)

Parts Required

You can connect to the sensor using DuPont style jumper wire.

 

Name	Link
ESP32		Aliexpress link Amazon Ebay
KX132		Aliexpress link
Connecting cables		Aliexpress link Amazon Ebay

 

Schematic/Connection

I used 3.3v from the ESP32 Lolin board I used for testing

I also used a Qwiic cable but if you do not have one of them there is an unpopulated set of pins you can solder a header to. This is how you would wire this up

 

Code Example

I installed the Sparkfun library using the Arduino ide

Click the Manage Libraries … menu item, search for KX132, and select the Sparkfun KX13x library like this

This is one of the examples that gets installed with the library, with a  few comments and unused lines removed.

#include <Wire.h>
#include <SparkFun_KX13X.h>

SparkFun_KX132 kxAccel;

outputData myData; // Struct for the accelerometer's data

void setup()
{

  Wire.begin();
  Serial.begin(115200);

  // Wait for the Serial monitor to be opened.
  while (!Serial)
    delay(50);

  if (!kxAccel.begin())
  {
    Serial.println("Could not communicate with the the KX13X");
    while (1)
      ;
  }
  Serial.println("Ready.");

  if (kxAccel.softwareReset())
    Serial.println("Reset.");

  // Give some time for the accelerometer to reset.
  delay(5);

  // Many settings for KX13X can only be
  // applied when the accelerometer is powered down.
  kxAccel.enableAccel(false);

  kxAccel.setRange(SFE_KX132_RANGE16G); // 16g Range
  kxAccel.enableDataEngine(); // Enables the bit that indicates data is ready.
  kxAccel.enableAccel();
}

void loop()
{
  // Check if data is ready.
  if (kxAccel.dataReady())
  {
    kxAccel.getAccelData(&myData);
    Serial.print("X: ");
    Serial.print(myData.xData, 4);
    Serial.print(" Y: ");
    Serial.print(myData.yData, 4);
    Serial.print(" Z: ");
    Serial.print(myData.zData, 4);
    Serial.println();
  }
  delay(500);
}

 

Output

When run and the sensor was moved around

Welcome.
Ready.
Reset.
X: 0.0005 Y: -0.6676 Z: -0.7608
X: 0.0464 Y: -0.6598 Z: -0.7544
X: 0.0600 Y: -0.6324 Z: -0.8428
X: 0.1459 Y: -0.6759 Z: -0.8589

Links

https://www.kionix.com/product/KX132-1211