How to Configure Raspberry Pi for Ethernet-TSN and PTP Synchronization

Introduction

The Raspberry Pi is a versatile microcomputer that can be configured for a variety of applications, including industrial automation. By utilizing Ethernet-TSN (Time-Sensitive Networking) and the 1588 Precision Time Protocol (PTP), you can achieve precise time synchronization among devices in an industrial setting. This tutorial will guide you through the steps required to configure your Raspberry Pi for this purpose.

Prerequisites

• Raspberry Pi (Model 3 or later recommended)
• Raspberry Pi OS installed (preferably Lite version)
• Ethernet cable
• Access to a terminal (SSH or direct connection)
• Basic knowledge of Linux commands

Parts/Tools

• Raspberry Pi
• MicroSD Card (8GB or larger)
• Power Supply for Raspberry Pi
• Ethernet Cable
• Computer for SSH access

Steps

Step 1: Set Up Raspberry Pi

1. Power on your Raspberry Pi.
2. Connect it to your network using an Ethernet cable.
3. Open a terminal on your computer and use SSH to connect:

ssh pi@

4. Enter the password (default is “raspberry”).

Step 2: Update the System

1. Run the following commands to update your Raspberry Pi:

sudo apt-get update
sudo apt-get upgrade

Step 3: Install Required Packages

1. Install the necessary packages for PTP:

sudo apt-get install ptpd linuxptp

Step 4: Configure PTP

1. Open the PTP configuration file:

sudo nano /etc/linuxptp/ptp4l.conf

2. Modify the configuration to suit your network. For example:

[global]
    domainNumber: 0
    priority1: 128
    clockClass: 248
    clockAccuracy: 0xFE
    offsetScaledLogVariance: 0xFFFF
    

3. Save and exit (Ctrl + X, then Y, then Enter).

Step 5: Start the PTP Daemon

1. Enable and start the PTP service:

sudo systemctl enable ptpd
sudo systemctl start ptpd

Step 6: Verify PTP Synchronization

1. Check the status of the PTP daemon:

sudo systemctl status ptpd

2. Monitor the synchronization status:

sudo pm2 start pm2-ptp

Troubleshooting

• Cannot connect via SSH: Ensure that the Raspberry Pi is powered on and connected to the network. Check the IP address.
• PTP daemon not starting: Check the configuration file for errors. Use journalctl -xe to view logs.
• No synchronization: Ensure that all devices on the network support PTP and are configured correctly.

Conclusion

Configuring a Raspberry Pi for Ethernet-TSN using the 1588 Precision Time Protocol can significantly enhance time synchronization in industrial automation systems. By following the steps outlined in this tutorial, you can successfully set up and verify your configuration to ensure precise timekeeping across your network. Experiment with additional configurations to optimize performance based on your specific application requirements.