Pavel Pisa, Czech Technical University in Prague
Jin Yang, University of Chinese Academy of Sciences
Michal Sojka, Czech Technical University in Prague

The QEMU system virtualization is often used for testing and development of embedded control systems. QEMU support not only basic architecture emulation but even precise emulation of many boards models but emulation of automotive and industrial control buses is missing. Presented project provides CAN controller emulation. The emulated controllers can be connected one to another inside one QEMU instance or can be connected to a host system virtual or physical SocketCAN supported CAN bus network if GNU/Linux is used as QEMU host system.

Implemented emulation consists of a simple CAN bus message delivery system which can be connected to SocketCAN socket on host side and QEMU emulated CAN controllers. The design is generic but only SJA1000 controller chip emulation has been implemented now. Significant advantage of selection of the chip used on PCI/PCIe standard boards is that such card emulation and configuration does not depend on target system architecture and system chip (if PCI is available and simulated on the system). This allows to “insert” CAN card to many systems (i.e. many PowerPC, ARM Versatile PB etc.). Emulated Kvaser PCI card is supported by mainline SocketCAN drivers as well as by LinCAN driver.

CAN emulation has been tested together with OrtCAN project which provides CANopen devices emulation and monitoring tools which can now communicate and be running on combined physical network and wirtual network spawning over more systems/QEMU instances.