/raspberry-pi-i2c-sts4x

Raspberry Pi driver for Sensirions STS4x temperature sensor

Primary LanguageCBSD 3-Clause "New" or "Revised" LicenseBSD-3-Clause

Sensirion Raspberry Pi I2C STS4x Driver

This document explains how to set up the STS4x sensor to run on a Raspberry Pi using the provided code.

Click here to learn more about the STS4x Sensor and Evaluation Kit.

Setup Guide

Connecting the Sensor

Your sensor has the four different connectors: VCC, GND, SDA, SCL. Use the following pins to connect your STS4x:

STS4x Raspberry Pi
VCC Pin 1 (3.3V)
GND Pin 6
SDA Pin 3
SCL Pin 5

Raspberry Pi

  • Install the Raspberry Pi OS on to your Raspberry Pi
  • Enable the I2C interface in the raspi-config
  • Download the driver for the Sensirion Github Page and extract the .zip on your Raspberry Pi
  • Compile the driver
    1. Open a terminal

    2. Navigate to the driver directory. E.g. cd ~/raspberry-pi-i2c-sts4x

    3. Run the make command to compile the driver

      Output:

      rm -f sts4x_i2c_example_usage
      cc -Os -Wall -fstrict-aliasing -Wstrict-aliasing=1 -Wsign-conversion -fPIC -I. -o sts4x_i2c_example_usage  sts4x_i2c.h sts4x_i2c.c sensirion_i2c_hal.h sensirion_i2c.h sensirion_i2c.c \
      	sensirion_i2c_hal.c sensirion_config.h sensirion_common.h sensirion_common.c sts4x_i2c_example_usage.c
      
  • Test your connected sensor
    • Run ./sts4x_i2c_example_usage in the same directory you used to compile the driver.

      Output:

      Serial number: 272952127
      Temperature: 25.09 °C
      Temperature: 25.08 °C
      Temperature: 25.08 °C
      Temperature: 25.10 °C 
      Temperature: 25.08 °C
      ...
      

Troubleshooting

Initialization failed

  • Ensure that you connected the sensor correctly: All cables are fully plugged in and connected to the correct pin.
  • Ensure that I2C is enabled on the Raspberry Pi. For this redo the steps on "Enable the I2C interface in the raspi-config" in the guide above.
  • Ensure that your user account has read and write access to the I2C device. If it only works with user root (sudo ./sts4x_i2c_example_usage), it's typically due to wrong permission settings.