# canlib

Contents

- canlib
  - List connected devices
  - Send and receive single frame
  - Send and receive CAN FD frame

The following sections contain sample code for inspiration on how to use Kvaser Python canlib.

## List connected devices

This code print some basic information (device name, EAN number and serial number) from all connected devices.

    from canlib import canlib

    num_channels = canlib.getNumberOfChannels()
    print("Found %d channels" % num_channels)
    for ch in range(0, num_channels):
        chdata = canlib.ChannelData(ch)
        print("%d. %s (%s / %s)" % (ch, chdata.device_name,
                                    chdata.card_upc_no,
                                    chdata.card_serial_no))

## Send and receive single frame

Here is some basic code to send and receive a single frame.

    from canlib import canlib, Frame
    from canlib.canlib import ChannelData

    def setUpChannel(channel=0,
                     openFlags=canlib.Open.ACCEPT_VIRTUAL,
                     bitrate=canlib.canBITRATE_500K,
                     outputControl=canlib.Driver.NORMAL):
        ch = canlib.openChannel(channel, openFlags)
        print("Using channel: %s, EAN: %s" % (ChannelData(channel).channel_name,
                                              ChannelData(channel).card_upc_no))
        ch.setBusOutputControl(outputControl)
        ch.setBusParams(bitrate)
        ch.busOn()
        return ch

    def tearDownChannel(ch):
        ch.busOff()
        ch.close()

    print("canlib version:", canlib.dllversion())

    ch0 = setUpChannel(channel=0)
    ch1 = setUpChannel(channel=1)

    frame = Frame(id_=100, data=[1, 2, 3, 4], flags=canlib.MessageFlag.EXT)
    ch1.write(frame)

    while True:
        try:
            frame = ch0.read()
            print(frame)
            break
        except (canlib.canNoMsg) as ex:
            pass
        except (canlib.canError) as ex:
            print(ex)

    tearDownChannel(ch0)
    tearDownChannel(ch1)

## Send and receive CAN FD frame

Here are some minimal code to send and receive a CAN FD frame.

    from canlib import canlib, Frame

        bitrate = canlib.canFD_BITRATE_500K_80P
        bitrate_data = canlib.canFD_BITRATE_2M_80P

        # open channel as CAN FD using the flag
        ch0 = canlib.openChannel(channel=0, flags=canlib.Open.CAN_FD)
        ch0.setBusOutputControl(drivertype=canlib.Driver.NORMAL)
        ch0.setBusParams(bitrate)
        ch0.setBusParamsFd(bitrate_data)
        ch0.busOn()

        ch1 = canlib.openChannel(channel=0, flags=canlib.Open.CAN_FD)
        ch1.setBusOutputControl(drivertype=canlib.Driver.NORMAL)
        ch1.setBusParams(bitrate)
        ch1.setBusParamsFd(bitrate_data)
        ch1.busOn()

        # set FDF flag to send using CAN FD
        # set BRS flag to send using higher bit rate in the data phase
        frame = Frame(id_=100, data=range(32),
                      flags=canlib.MessageFlag.FDF | canlib.MessageFlag.BRS)
        print('Sending', frame)
        ch0.write(frame)

        frame = ch1.read(timeout=1000)
        print('Receiving', frame)

        ch0.busOff()
        ch1.busOff()