Customize a Intrusion Detection System for serial communication

Most of the Intrusion detection Systems I know of is for IP Communication. But, lets assume that I have serial communication, i.e. CAN or RS485. On this serial Communication there are customized protocols communicating, such that the analysis of traffic can be pretty static.

Does anyone know of an IDS which is possible to customize for this purpose?

It does not have to be a finished Product, just a reference to a paper or document would be nice.