SocketCAN

SocketCAN is the Linux kernel’s way of exposing a CAN bus, and this transport is a client of it. It is one of the two concrete CAN transports; the other is the in-memory Virtual CAN.

Because it goes through the kernel, PLC4X does not handle bus access, arbitration or timing - the CAN layer below does. It has been used successfully with the vcan and gs_usb drivers.

Linux only. SocketCAN has its own frame representation - fixed-length frames (a CAN 2.0A frame always takes 16 bytes) and a 29-bit identifier field where a standard CAN frame uses 11, with the remaining 3 bits carrying flags.

Transport syntax

{name of the CAN interface}

Example

canopen:can-socketcan://can0
canopen:can-socketcan://vcan0?can-socketcan.read-timeout-ms=500

The interface can also be named with the can-socketcan.interface-name option instead; the address segment wins if both name one. One of the two has to be given.

Name

Type

Default Value

Required

Description

Name

SocketCAN

Code

can-socketcan

Maven Dependency

<dependency>
  <groupId>org.apache.plc4x</groupId>
  <artifactId>plc4j-transports-can-socketcan</artifactId>
  <version>1.0.0</version>
</dependency>

Config options:

can-socketcan.interface-name

STRING

Linux CAN interface name (e.g., "can0", "vcan0"). Alternative to naming the interface in the address segment of the connection string, which takes precedence.

can-socketcan.reuse-interface

BOOLEAN

false

Share CAN socket across multiple transport instances on the same interface

can-socketcan.read-timeout-ms

INT

1000

Read timeout in milliseconds for blocking reads on the CAN socket

can-socketcan.filter-ids

STRING

Comma-separated list of accepted CAN IDs (decimal or 0x hex). Empty means accept all.

can-socketcan.filter-range-start

INT

-1

Start of accepted CAN ID range (inclusive). -1 means no range filtering.

can-socketcan.filter-range-end

INT

-1

End of accepted CAN ID range (inclusive). -1 means no range filtering.