A simple command line tool for Raspberry-Pi to read a SHT31 sensor over the I2C bus.

There are a number of arguments you can use:

Usage: read_sht31 [arguments]
 -h|--help   Display this help.
 -s          Get the sensor status.
 -t1 -t0     Enable/disable heater.
 -a0 -a1     Select the chip address. 0 is the default.
 -b0 -b1     Select the bus. 1 is the default.
 -d          Show debugging messages.

If you call the command, you will get JSON output:

$ read_sht32
{ "temperature_celsius": 24.8, "relative_humidity": 28.4 }

The idea is to call this command from your script and parse the returned JSON output.

In order to compile and install the tool on your Raspberry-Pi, you need to install the compiler, CMake and the I2C-Tools first:

sudo apt install gcc cmake i2c-tools

Download the files of this git repository to a sub directory in your home directory. In this example, I downloaded the files to the directory /home/pi/read_sht31.

Now create a separate build directory. In this example, I create the directory /home/pi/build_read_sht31.

Next switch to the build directory, execute cmake to create the build script. Build the executable with make and install the executable in your system with sudo make install.

cd build_read_sht31
cmake ../read_sht31
make
sudo make install

Copyright (c) 2020 by Lucky Resistor.

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see https://www.gnu.org/licenses/.