CANsub now supports PTP: <10 µs cross-device time sync

Need to stream CAN FD data from multiple CAN interfaces - with timestamps you can compare perfectly across devices?

With FW 02.05.00, the CANsub now supports the Precision Time Protocol (PTP) via both Ethernet and USB.

Every CANsub already timestamps RX/TX frames in hardware with 1 µs resolution - but each device clock drifts over time.

As a result, multi-device setups (e.g. 8 x CAN across 2 x CANsub.4) suffer from drifting timestamps - and at best you may keep them within ~2 ms (i.e. ~2000 µs) of each other.

However, PTP solves this by syncing all CANsub devices to one shared network clock:

• Plug & play: PTP is enabled by default. The CANsub detects a compatible PTP master on the network and starts tracking it within 10-20s - no configuration needed
• Ethernet + USB: Sync works over Ethernet/USB, so you can use it on a LAN with an Ethernet switch - or with multiple CANsubs via USB to a single PC
• <10 µs via software: Use a Linux PC or Pi running the free ptp4l tool as your PTP master to go from a cross-device time delta of ~1000-2000 µs to <10 µs (99%+ less)
• ~1-10 µs via hardware: Add a standalone hardware PTP master to simplify your setup - and reach ~1-10 µs cross-device sync plus near perfect absolute sync
• Standard IEEE 1588: The CANsub supports the default IEEE 1588 profile via IPv4 UDP multicast - sharing a common time base with other PTP-synced data sources
• Status via REST + display: The PTP sync status can be polled via REST - and the CANsub LCD and webCAN show a time sync icon while tracking the master

webCAN update: Grouped signal filters + 30 min chart views

With CANsub FW 02.05.00, our free browser-based webCAN GUI gets several improvements for working with DBC-decoded CAN data - in particular when you use large DBC files or review longer periods of data.

• PTP support: webCAN supports PTP by allowing a PTP master to specify the absolute time reference - thus enabling you to stream data in perfect sync vs. the absolute time and other CANsubs on your network
• Grouped signal filters: The filter panel now groups signals under their message, with expand/collapse and a per-message checkbox. Show/hide all signals of a message with one click - and keep an overview with large DBC files like J1939
• 30 min chart views: When browsing historical data, the chart view now supports time windows of up to 30 min. Combined with the 2M frame buffer, you can review long-term trends (e.g. temperatures or SoC) - and zoom in on the details
• DBC comments on hover: Hover a message or signal in the decoded Trace and Summary views to see its DBC comment - useful when working with large DBC files
• Dark mode: Switch between light and dark mode via the new toggle in the header
• Device status + control: Reboot the CANsub via a new button, see a green lock icon when mTLS is enabled - and get a reload prompt if a device reset is detected. The status bar also blanks stale values and reflects bus disconnects

New: GPS-based PTP master for your CANsubs

Need to sync multiple CANsub devices to one shared clock - with <10 µs absolute sync via PTP (Precision Time Protocol)?

We have now added the TM2000B GPS-based PTP grandmaster clock to our range of CANsub accessories. Connect it to your Ethernet switch and every CANsub on the network syncs to it - aligning all CAN frame timestamps to true absolute time.

In our recent PTP post, we explained how a Linux PC or Raspberry Pi running a software PTP master can bring multiple CANsubs within 10 µs of each other. The TM2000B is a plug & play, standalone and pro specs alternative - offering GPS-based absolute time and PTP messages timestamped in hardware - with no host to maintain.

In our tests with the TM2000B, multiple CANsubs reach a cross-device sync of +/- 1 µs!

Key features include:

• <10 µs sync: Sync all CANsub devices on your network to one clock - below 10 µs
• GPS based: GPS reference enables true UTC timestamps, not a drifting PC time
• 2 min setup: Deploy + configure via your browser. Optional Power-over-Ethernet
• Standalone: Runs offline with no internet, host software or scripts to maintain
• Holdover: OCXO oscillator keeps serving stable time if the GPS signal is lost
• Scalable: One unit serves any number of CANsub devices across your LAN

CAN bus - the ultimate guide PDF [2026]

Our popular free 'ultimate guide' PDF just got its first update since 2023 - and it has grown and improved a lot!

The guide bundles our 'simple intros' into one PDF that you can read offline, print or share with new colleagues and students.

This is a must-have for any automotive/industrial engineer!

• 17 intros: All 100% up-to-date - including 5 new intros!
• 240+ pages: More than 100 new pages of CAN insights!
• Updates: Keep subscribing to our newsletter to get any future PDF updates

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