[Python] Communication through CAN bus interface is not working

I have Python code running on a Linux-based device which has the following OS specifications:

NAME=Buildroot
VERSION=2020.11.1


This device is connected to a PLC using a three-wire interface (CAN_H, CAN_L, and GND).

I have written code that sends a message to the PLC using the CAN bus protocol. This is being done with the python-can package.

I have the following code:

import can

def send():
# USB interface
#bus = can.interface.Bus(bustype='pcan', channel='PCAN_USBBUS1', bitrate=500000)
# On Linux
bus = can.interface.Bus(bustype='socketcan', channel='vcan0', bitrate=500000)
# On Windows
#bus = can.interface.Bus(bustype='serial', channel='COM1', bitrate=500000)
msg = can.Message(arbitration_id=0x68005,data=[0x10,0x11,0x12],is_extended_id=True)
try:
bus.send(msg)
print("Message sent on {}".format(bus.channel_info))
except can.CanError:
print("Message NOT sent")


if __name__ == '__main__':
send()


The problem is that the device is not sending any data to the PLC. This is probably due to incorrect options set for bustype and channel.

What can I provide for bustype and channel for this physical interface with three CAN wires?

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