What is a CAN-Bus? A CAN-Bus is a Controller Area Network that allows microcontrollers to communicate with one another over a twisted pair of wires without a host computer via a gateway. Simply put, sub-components of a system can "talk" to one another and components of other systems freely to accomplish desired tasks.
Why would this be important you ask? Well, on today’s cars there can be up to 50 electronic control units (ECU) that operate various tasks from: keeping the engine running, shifting the transmission, monitoring the temperature inside the cabin of the car and regulating it and rolling up or down the windows. It would be easy to imagine the amount of wiring it would take to accomplish this all. In fact, vehicles today that don’t run on CAN-bus systems can have over three miles of wiring with a added weight of several hundred pounds. The increase in wieght directly translates to lower fuel economy, and higher fuel costs at the pumps, which, as we all have seen recently, can mean a lot more money when filling up.
What are the applications of this type of network? This application was first implemented in 1986 by Robert Bosch to be used in the automotive industry to lessen the amount of wiring that was rapidly becoming the norm with the advent of on-board computer systems. The first vehicle to use a CAN-Bus was a 1986 BMW 850 Coupe.
However, the application has broaden itself out into many other industries:
· Marine control and navigation systems
· Elevator control systems
· Agricultural machinery
· Production line control systems
· Machine tools
· Large optical telescopes
· Photo copiers
· Medical systems
· Paper making and processing machinery
· Packaging machinery
· Textile production machinery
 | Here is a typical "hardwired" system with dedicated wires for inputs and outputs. |
Here is the same system now on a CAN-Bus system. Notice the drastic reduction in wiring. |  |
