system/devices/can.rst

1 CAN Bus Emulation Support
3 The CAN bus emulation provides mechanism to connect multiple
4 emulated CAN controller chips together by one or multiple CAN buses
6 can be connected to host system CAN API (at this time only Linux
9 The concept of buses is generic and different CAN controllers
10 can be implemented.
16 The PCI addon card hardware has been selected as the first CAN
17 interface to implement because such device can be easily connected
20 In 2020, CTU CAN FD controller model has been added as part
28 CAN subsystem for RTEMS. But lack of common environment for code and RTEMS
31 to work on CAN hardware emulation on QEMU.
33 Examples how to use CAN emulation for SJA1000 based boards
35 When QEMU with CAN PCI support is compiled then one of the next
36 CAN boards can be selected
38 (1) CAN bus Kvaser PCI CAN-S (single SJA1000 channel) board. QEMU startup options::
40     -object can-bus,id=canbus0
43 Add "can-host-socketcan" object to connect device to host system CAN bus::
45     -object can-host-socketcan,id=canhost0,if=can0,canbus=canbus0
47 (2) CAN bus PCM-3680I PCI (dual SJA1000 channel) emulation::
49     -object can-bus,id=canbus0
54     -object can-bus,id=canbus0
55     -object can-bus,id=canbus1
58 (3) CAN bus MIOe-3680 PCI (dual SJA1000 channel) emulation::
71       -object can-bus,id=canbus0 \
72       -object can-host-socketcan,id=canhost0,if=can0,canbus=canbus0 \
84       -object can-bus,id=canbus0 \
85       -object can-host-socketcan,id=canhost0,if=can0,canbus=canbus0 \
88 The CAN interface of the host system has to be configured for proper
93   ip link set can0 type can bitrate 1000000
96 Virtual (host local only) can interface can be used on the host
101 The CAN interface on the host side can be used to analyze CAN
102 traffic with "candump" command which is included in "can-utils"::
106 CTU CAN FD support examples
108 This open-source core provides CAN FD support. CAN FD drames are
110 CAN FD capable.
113 ctucan_pci). The default build defines two CTU CAN FD cores
117 Linux system (SocketCAN used) and to both CTU CAN FD cores emulated
118 on the corresponding PCI card expects that host system CAN bus
126       -object can-bus,id=canbus0-bus \
127       -object can-host-socketcan,if=can0,canbus=canbus0-bus,id=canbus0-socketcan \
131 Setup of CTU CAN FD controller in a guest Linux system::
136   for ifc in /sys/class/net/can* ; do
152     /bin/ip link set $ifc type can bitrate 1000000 dbitrate 10000000 fd on
156 The test can run for example::
160 in the guest system and next commands in the host system for basic CAN::
164 for CAN FD without bitrate switch::
172 The test can also be run the other way around, generating messages in the
179 …(1) `CAN related projects at Czech Technical University, Faculty of Electrical Engineering <http:/…
180 …(2) `Repository with development can-pci branch at Czech Technical University <https://gitlab.fel.…
182 …its use with CANopen emulation <http://cmp.felk.cvut.cz/~pisa/can/doc/rtlws-17-pisa-qemu-can.pdf>`_
183 …(5) `GNU/Linux, CAN and CANopen in Real-time Control Applications Slides from LinuxDays 2017 (incl…
184  (6) `Linux SocketCAN utilities <https://github.com/linux-can/can-utils>`_
185 …(7) `CTU CAN FD project including core VHDL design, Linux driver, test utilities etc. <https://git…
186 …(8) `CTU CAN FD Core Datasheet Documentation <http://canbus.pages.fel.cvut.cz/ctucanfd_ip_core/doc…
187 …(9) `CTU CAN FD Core System Architecture Documentation <http://canbus.pages.fel.cvut.cz/ctucanfd_i…
188 …(10) `CTU CAN FD Driver Documentation <https://canbus.pages.fel.cvut.cz/ctucanfd_ip_core/doc/linux…