Single-Wire CAN Bus Without Transceivers
Sometimes you have a CAN equipped processor on a low cost board but it has no CAN transceiver chips. Here is a method
that can be used to create a small demonstration network with such a board. There will be no noise immunity and you might
have to lower the speed….but many experimenters have made this work satisfactorily. Use a signal diode similar to 1N914
or 1N4148. Power supply diodes usually do not have a fast enough recovery time for CAN to function.