CAN BUS Tutorial
This article is under construction
CAN BUS (Controller Area Network) is a very deterministic BUS heavily used in the automotive industry. It is a half-duplex BUS, that operates using a pair of differential signals. Typically, the speed standards are 100K, 250K, 500K or 1Mbit.
CAN BUS Frame
Unlike other BUSes that can be up and running without any external hardware, CAN BUS REQUIRES a voltage transceiver that converts logical Rx/Tx pins into a single differential pair wire that is hooked up on the CAN BUS.
OBDII standard uses CAN BUS to communicate to the ECU. You can connect a CAN controller to an OBDII port easily by using an OBDII to Serial cable. Since this kind of cable doesn't convert the CAN voltage signals to logical signals that a microcontroller can understand, you would also need an MCP2561 based transceiver which would allow your controller to be interfaced to an OBDII port.