cantools 4.1.1

CAN BUS tools.

About

CAN BUS tools.

• DBC file mangling.

• candump output decoder.

Installation

pip install cantools

Example usage

Scripting

An example parsing and using a small DBC-file:

>>> import cantools
>>> from pprint import pprint
>>> db = cantools.db.File()
>>> db.add_dbc_file('tests/files/motohawk.dbc')
>>> db
version('1.0')

node('PCM1', None)
node('FOO', None)

message('ExampleMessage', 0x1f0, 8, 'Example message used as template in MotoHawk models.')
  signal('Temperature', 7, 12, 'big_endian', True, 0.01, 250, 229.53, 270.47, 'degK', None, None)
  signal('AverageRadius', 1, 6, 'big_endian', False, 0.1, 0, 0.0, 5.0, 'm', None, '')
  signal('Enable', 0, 1, 'big_endian', False, 1.0, 0, 0.0, 0.0, '-', None, None)

>>> db.messages
[message('ExampleMessage', 0x1f0, 8, 'Example message used as template in MotoHawk models.')]
>>> example_message = db.messages[0]
>>> example_message.comment
'Example message used as template in MotoHawk models.'
>>> pprint(example_message.signals)
[signal('Temperature', 7, 12, 'big_endian', True, 0.01, 250, 229.53, 270.47, 'degK', None, None),
 signal('AverageRadius', 1, 6, 'big_endian', False, 0.1, 0, 0.0, 5.0, 'm', None, ''),
 signal('Enable', 0, 1, 'big_endian', False, 1.0, 0, 0.0, 0.0, '-', None, None)]
>>> db.nodes
[node('PCM1', None), node('FOO', None)]
>>> db.version
'1.0'
>>>

The example continues encoding a message and sending it on a CAN bus using the python-can package.

>>> import can
>>> can.rc['interface'] = 'socketcan_ctypes'
>>> can.rc['channel'] = 'vcan0'
>>> can_bus = can.interface.Bus()
>>> data = example_message.encode({'Temperature': 250.1, 'AverageRadius': 3.2, 'Enable': 1})
>>> message = can.Message(arbitration_id=example_message.frame_id, data=data)
>>> can_bus.send(message)
>>>

See the test suite for additional examples: https://github.com/eerimoq/cantools/blob/master/tests/test_cantools.py

Command line tool

Decode CAN frames captured with the Linux program candump.

$ candump vcan0 | cantools decode motohawk.dbc
  vcan0  000001F0   [7]  01 FA 0F 00 00 00 00 :: ExampleMessage(Temperature: 249.88 degK, AverageRadius: 0.0 m, Enable: 1.0 -)
  vcan0  000001F0   [7]  01 FA 0F 00 00 00 00 :: ExampleMessage(Temperature: 249.88 degK, AverageRadius: 0.0 m, Enable: 1.0 -)
  vcan0  000001F0   [7]  01 FA 0F 00 00 00 00 :: ExampleMessage(Temperature: 249.88 degK, AverageRadius: 0.0 m, Enable: 1.0 -)

Contributing

1. Fork the repository.

2. Implement the new feature or bug fix.

3. Implement test case(s) to ensure that future changes do not break legacy.

4. Run the test suite for Python 2 and Python 3. Make sure all tests pass.

   python setup.py test
   python3 setup.py test

5. Create a pull request.