How to install a rx callback with python-can?

Question

I'd like to have a function to receive incoming CANbus frames asynchronously. I wrote the following, but the following issue:

    can.rxcallback(0, callback)
AttributeError: module 'can' has no attribute 'rxcallback'

My code is as follow:

def reception():
    global count
    data = [0, 0, 0, memoryview(bytearray(8))]

    def callback(bus, reason):
        global count
        count += 1
        bus.recv(0, list=data)
        if reason == 0:
            pass
        elif reason == 1:
            pass  # fifo full
        elif reason == 2:
            # fifo overflow
            raise Exception("fifo overflow")

    can.rxcallback(0, callback)

score 0 · Accepted Answer · answered Jul 22 '22 at 20:02

Taken straight form python-can's documentation:

def print_message(msg: can.Message) -> None:
    """Regular callback function. Can also be a coroutine."""
    print(msg)


notifier = can.Notifier(bus, [print_message])
...
notifier.stop()

You create an instance of Notifier and register a list of listeners.

A listener is either a function taking a parameter of type can.Message or an instance of Listener.

After you have received all messages, call stop() on the notifier.

There is no method like rxcallback or similar on python-can.

How to install a rx callback with python-can?

1 Answers1