PSLab Notebooks

This repository (https://github.com/fossasia/pslab-notebooks) contains a series of tutorials and exercises for the Pocket Science Lab (PSLab) Python library.

Downloading the notebooks

Download the tutorial notebooks by either

• git cloneing this repository (https://github.com/fossasia/pslab-notebooks)
• cd into it

or

• Download this repository as a ZIP archive by clicking the green '<> Code'-button in the Github web interface, and then select "Download ZIP"
• Unpack the ZIP archive and cd into it

Requirements

The following software is required to run the notebooks:

• Python 3.9 or later
• On some Linux distributions (notably Debian, Ubuntu) the packages python3-pip and python3-venv must be installed from the distribution's repositories

Additional Linux-specific requirements

Windows and MacOS users can skip this section.

Your user most likely does not have permission to access serial ports, which means you can't talk to the PSLab yet. You need to become a member of the group which owns the serial port device file. The device file is typically called '/dev/ttyUSB0', and the owner group is usually either 'dialout' (on Debian-, RedHat-, and Suse-based systems) or 'uucp' (on Arch-based systems).

Check which group owns the serial port with this command (replace '/dev/ttyUSB0' with the actual path of your device file, if necessary):

stat -c %G /dev/ttyUSB0

The output from this command should be a single group name, e.g.

dialout

You need to be a member of this group. Check if you already are with (replace 'dialout' with the name of the owner group, if necessary):

getent group dialout

The output of this command should be a line from '/etc/group', e.g.

dialout:x:20:alexander

If your username is present in the response, you are already a member of the group. You can move on to the next section of the guide.

If your username is not present in the response, you are not a member of the group which owns the serial port. On most distros, this can be done with (replace 'dialout' with the name of the owner group, if necessary, and 'username' with your username):

usermod -aG dialout username

You need to log out and log back in for the group change to take effect.

Installing pslab

• Create a Python venv (virtual environment) with python3 -m venv venv
• Activate the virtual environment.
  • On Linux or MacOS, run source ./venv/bin/activate
  • On Windows, run ./venv/Scripts/activate.bat
• Install the dependencies: Run pip install -r requirements.txt

Verifying the installation

Once installed, connect the PSLab board and verify that you can connect to it by running pslab collect -c 1 -d 0.00001 oscilloscope. This will sample the voltage on the PSLab's CH1 pin for 10 µs. The output should look something like:

Timestamp,CH1
0.0,0.016129032258064058
0.5,0.016129032258064058
1.0,0.016129032258064058
1.5,0.016129032258064058
2.0,0.016129032258064058
2.5,0.016129032258064058
3.0,0.016129032258064058
3.5,0.016129032258064058
4.0,0.016129032258064058
4.5,0.016129032258064058
5.0,0.016129032258064058
5.5,0.016129032258064058
6.0,0.016129032258064058
6.5,0.016129032258064058
7.0,0.016129032258064058
7.5,0.016129032258064058
8.0,0.016129032258064058
8.5,0.016129032258064058
9.0,0.016129032258064058
9.5,0.016129032258064058

If you get an error saying serial.serialutil.SerialException: Device not found., try another USB-cable.

Once this installation is complete, launch Jupyter Notebooks by running jupyter notebook. A web interface should open in your default browser, showing the current directory. You can open notebooks (.ipynb-files) by clicking on them.