Version v4.6.1 - 2025-08-12

Fixed

• Fix initialisation of an slcan bus, when setting a bitrate. When using CAN 2.0 (not FD), the default setting for data_bitrate was invalid, causing an exception. (#1978)

🚀 Highlights

• 🆕 New CLI tool: can_bridge — bridge two physical CAN buses in software via python -m can.bridge.
• 📡 Expanded protocol support:
  • 11-bit identifiers, remote frames, and error frames in the serial interface.
  • CAN FD support in slcan for CANable 2.0 devices.
  • Error message support in the socketcand interface.
  • Remote frame support in TRCReader.
• 🖥 Windows support: Added support for the udp_multicast interface on Windows.
• 🔔 Notifier improvements:
  • Track active Notifiers and use them as context managers.
  • New helper: Notifier.find_instances(bus) to discover active Notifiers.
• 🛠 Better CLI integration: Public functions can.cli.add_bus_arguments and can.cli.create_bus_from_namespace for downstream packages to easily configure and parse python-can bus options.

Added

• Add support for 11-bit identifiers in the serial interface. (#1758)
• Add context manager support and active instance tracking to Notifier, plus Notifier.find_instances(bus). (#1890)
• Add Windows support to udp_multicast interface. (#1914)
• Add FD support to slcan according to CANable 2.0 implementation. (#1920)
• Add support for error messages to the socketcand interface. (#1941)
• Add support for remote and error frames in the serial interface. (#1948)
• Add public functions can.cli.add_bus_arguments and can.cli.create_bus_from_namespace for creating bus command line options. Currently downstream packages need to implement their own logic to configure python-can buses. Now python-can can create and parse bus options for third party packages. (#1949)
• Add support for remote frames to TRCReader. (#1953)
• Mention the python-can-candle package in the plugin interface section of the documentation. (#1954)
• Add new CLI tool python -m can.bridge (or just can_bridge) to create a software bridge between two physical buses. (#1961)

🔧 Changed

• Allow sending Classic CAN frames with a DLC value larger than 8 using the socketcan interface. (#1851)
• Rename the gs_usb extra dependency to gs-usb. (#1945)
• New PEP 735 dependency groups lint, docs and test. (#1945)
• Update dependency name from zlgcan-driver-py to zlgcan. (#1946)
• Use ThreadPoolExecutor in detect_available_configs() to reduce runtime and add timeout parameter. (#1947)
• Update contribution guide. (#1960)

🗑 Removed

• Remove support for Python 3.8. (#1931)
• Unknown command line arguments ("extra args") are no longer passed down to can.Bus() instantiation. Use the --bus-kwargs argument instead. (#1949)
• Remove can.io.generic.BaseIOHandler class. Improve can.io.* type annotations by using typing.Generic. (#1951)

🐞 Fixed

• Fix a bug in slcanBus.get_version() and slcanBus.get_serial_number(): If any other data was received during the function call, then None was returned. (#1904)
• Fix incorrect padding of CAN FD payload in BlfReader. (#1906)
• Set correct message direction for messages received with kvaser interface and receive_own_messages=True. (#1908)
• Fix timestamp rounding error in BlfWriter. (#1921)
• Fix timestamp rounding error in BlfReader. (#1927)
• Handle timer overflow message and build timestamp according to the epoch in the ixxat interface. (#1934)
• Avoid unsupported ioctl function call to allow usage of the udp_multicast interface on MacOS. (#1940)
• Fix configuration file parsing for the state bus parameter. (#1957)
• Mf4Reader: support non-standard CAN_DataFrame.Dir values in mf4 files created by ihedvall/mdflib. (#1967)
• PcanBus: Set Message.channel attribute in PcanBus.recv(). (#1969)

Features

• gs_usb command-line support (and documentation updates and stability fixes) by @BenGardiner in #1790
• Faster and more general MF4 support by @cssedev in #1892
• ASCWriter speed improvement by @pierreluctg in #1856
• Faster Message string representation by @pierreluctg in #1858
• Added Netronic's CANdo and CANdoISO adapters interface by @belliriccardo in #1887
• Add autostart option to BusABC.send_periodic() to fix issue #1848 by @SWolfSchunk in #1853
• Improve TestBusConfig by @zariiii9003 in #1804
• Improve speed of TRCReader by @lebuni in #1893

Bug Fixes

• Fix Kvaser timestamp by @zariiii9003 in #1878
• Set end_time in ThreadBasedCyclicSendTask.start() by @zariiii9003 in #1871
• Fix regex in _parse_additional_config() by @zariiii9003 in #1868
• Fix for #1849 (PCAN fails when PCAN_ERROR_ILLDATA is read via ReadFD) by @bures in #1850
• Period must be >= 1ms for BCM using Win32 API by @pierreluctg in #1847
• Fix ASCReader Crash on "Start of Measurement" Line by @RitheeshBaradwaj in #1811
• Resolve AttributeError within NicanError by @vijaysubbiah20 in #1806

Miscellaneous

• Fix CI by @zariiii9003 in #1889
• Update msgpack dependency by @zariiii9003 in #1875
• Add tox environment for doctest by @zariiii9003 in #1870
• Use typing_extensions.TypedDict on python < 3.12 for pydantic support by @NickCao in #1845
• Replace PyPy3.8 with PyPy3.10 by @zariiii9003 in #1838
• Fix slcan tests by @zariiii9003 in #1834
• Test on Python 3.13 by @zariiii9003 in #1833
• Stop notifier in examples by @zariiii9003 in #1814
• Use setuptools_scm by @zariiii9003 in #1810
• Added extra info for Kvaser dongles by @FedericoSpada in #1797
• Socketcand: show actual response as well as expected in error by @liamkinne in #1807
• Refactor CLI filter parsing, add tests by @zariiii9003 in #1805
• Add zlgcan to docs by @zariiii9003 in #1839

Bug Fixes

• Remove abstractmethod decorator from Listener.stop() (#1770, #1795)
• Fix SizedRotatingLogger file suffix bug (#1792, #1793)
• gs_usb: Use BitTiming class internally to configure bitrate (#1747, #1748)
• pcan: Fix unpack error in PcanBus._detect_available_configs() (#1767)
• socketcan: Improve error handling in SocketcanBus.__init__() (#1771)
• socketcan: Do not log exception on non-linux platforms (#1800)
• vector, kvaser: Activate channels after CAN filters were applied (#1413, #1708, #1796)

Features

• kvaser: Add support for non-ISO CAN FD (#1752)
• neovi: Return timestamps relative to epoch (#1789)
• slcan: Support CANdapter extended length arbitration ID (#1506, #1528)
• slcan: Add support for listen_only mode (#1496)
• vector: Add support for listen_only mode (#1764)

Features

• TRC 1.3 Support: Added support for .trc log files as generated by PCAN Explorer v5 and other tools, expanding compatibility with common log file formats (#1753).
• ASCReader refactor: improved the ASCReader code (#1717).
• SYSTEC Interface Enhancements: Added the ability to pass an explicit DLC value to the send() method when using the SYSTEC interface, enhancing flexibility for message definitions (#1756).
• Socketcand Beacon Detection: Introduced a feature for detecting socketcand beacons, facilitating easier connection and configuration with socketcand servers (#1687).
• PCAN Driver Echo Frames: Enabled echo frames in the PCAN driver when receive_own_messages is set, improving feedback for message transmissions (#1723).
• CAN FD Bus Connection for VectorBus: Enabled connecting to CAN FD buses without specifying bus timings, simplifying the connection process for users (#1716).
• Neousys Configs Detection: Updated the detection mechanism for available Neousys configurations, ensuring more accurate and comprehensive configuration discovery (#1744).

Bug Fixes

• Send Periodic Messages: Fixed an issue where fixed-duration periodic messages were sent one extra time beyond their intended count (#1713).
• Vector Interface on Windows 11: Addressed compatibility issues with the Vector interface on Windows 11, ensuring stable operation across the latest OS version (#1731).
• ASCWriter Millisecond Handling: Corrected the handling of milliseconds in ASCWriter, ensuring accurate time representation in log files (#1734).
• Various minor bug fixes: Addressed several minor bugs to improve overall stability and performance.

Miscellaneous

• Invert default value logic for BusABC._is_shutdown. (#1774)
• Implemented various logging enhancements to provide more detailed and useful operational insights (#1703).
• Updated CI to use OIDC for connecting GitHub Actions to PyPi, improving security and access control for CI workflows.
• Fix CI to work for MacOS (#1772).

The release also includes various other minor enhancements and bug fixes aimed at improving the reliability and performance of the software.

Features

• TRC 1.3 Support: Added support for .trc log files as generated by PCAN Explorer v5 and other tools, expanding compatibility with common log file formats (#1753).
• ASCReader refactor: improved the ASCReader code (#1717).
• SYSTEC Interface Enhancements: Added the ability to pass an explicit DLC value to the send() method when using the SYSTEC interface, enhancing flexibility for message definitions (#1756).
• Socketcand Beacon Detection: Introduced a feature for detecting socketcand beacons, facilitating easier connection and configuration with socketcand servers (#1687).
• PCAN Driver Echo Frames: Enabled echo frames in the PCAN driver when receive_own_messages is set, improving feedback for message transmissions (#1723).
• CAN FD Bus Connection for VectorBus: Enabled connecting to CAN FD buses without specifying bus timings, simplifying the connection process for users (#1716).
• Neousys Configs Detection: Updated the detection mechanism for available Neousys configurations, ensuring more accurate and comprehensive configuration discovery (#1744).

Bug Fixes

• Send Periodic Messages: Fixed an issue where fixed-duration periodic messages were sent one extra time beyond their intended count (#1713).
• Vector Interface on Windows 11: Addressed compatibility issues with the Vector interface on Windows 11, ensuring stable operation across the latest OS version (#1731).
• ASCWriter Millisecond Handling: Corrected the handling of milliseconds in ASCWriter, ensuring accurate time representation in log files (#1734).
• Various minor bug fixes: Addressed several minor bugs to improve overall stability and performance.

Miscellaneous

• Invert default value logic for BusABC._is_shutdown. (#1774)
• Implemented various logging enhancements to provide more detailed and useful operational insights (#1703).
• Updated CI to use OIDC for connecting GitHub Actions to PyPi, improving security and access control for CI workflows.
• Fix CI to work for MacOS (#1772).

The release also includes various other minor enhancements and bug fixes aimed at improving the reliability and performance of the software.

v4.3.2-rc.4

Update CI.yml workflow

Allow release without tests

This is a bugfix release.

Bug Fixes

• Fix socketcand erroneously discarding frames (#1700)
• Fix initialization order in EtasBus (#1693, #1704)

Documentation

• Fix install instructions for neovi (#1694, #1697)

In this release, we've raised the minimum Python version to 3.8, added several new features to the API and as always plenty of bug fixes and interface improvements.

Breaking Changes

• Raise Minimum Python Version to 3.8 (#1597)
• Do not stop notifier if exception was handled (#1645)

Bug Fixes

• Vector: channel detection fails, if there is an active flexray channel (#1634)
• ixxat: Fix exception in 'state' property on bus coupling errors (#1647)
• NeoVi: Fixed serial number range (#1650)
• PCAN: Fix timestamp offset due to timezone (#1651)
• Catch pywintypes.error in broadcast manager (#1659)
• Fix BLFReader error for incomplete or truncated stream (#1662)
• PCAN: remove Windows registry check to fix 32bit compatibility (#1672)
• Vector: Skip the can_op_mode check if the device reports can_op_mode=0 (#1678)
• Vector: using the config from detect_available_configs might raise XL_ERR_INVALID_CHANNEL_MASK error (#1681)

Features

API

• Add modifier_callback parameter to BusABC.send_periodic for auto-modifying cyclic tasks (#703)
• Add protocol property to BusABC to determine active CAN Protocol (#1532)
• Change Bus constructor implementation and typing (#1557)
• Add optional strict parameter to relax BitTiming & BitTimingFd Validation (#1618)
• Add BitTiming.iterate_from_sample_point static methods (#1671)

IO

• Can Player compatibility with interfaces that use additional configuration (#1610)

Interface Improvements

• Kvaser: Add BitTiming/BitTimingFd support to KvaserBus (#1510)
• Ixxat: Implement detect_available_configs for the Ixxat bus. (#1607)
• NeoVi: Enable send and receive on network ID above 255 (#1627)
• Vector: Send HighPriority Message to flush Tx buffer (#1636)
• PCAN: Optimize send performance (#1640)
• PCAN: Support version string of older PCAN basic API (#1644)
• Kvaser: add parameter exclusive and override_exclusive (#1660)
• socketcand: Add parameter tcp_tune to reduce latency (#1683)

Miscellaneous

• Distinguish Text/Binary-IO for Reader/Writer classes. (#1585)
• Convert setup.py to pyproject.toml (#1592)
• activate ruff pycodestyle checks (#1602)
• Update linter instructions in development.rst (#1603)
• remove unnecessary script files (#1604)
• BigEndian test fixes (#1625)
• align ID: in can.Message string (#1635)
• Use same configuration file as Linux on macOS (#1657)
• We do not need to account for drift when we USE_WINDOWS_EVENTS (#1666, #1679)
• Update linters, activate more ruff rules (#1669)
• Add Python 3.12 Support / Test Python 3.12 (#1673)