= CAN =
CAN bus (for controller area network) is a vehicle bus standard designed to allow microcontrollers and devices to communicate with each other within a vehicle without a host computer.

http://en.wikipedia.org/wiki/Controller_area_network

= FMS standard =
In order to be compliant with FMS standard, truck manufacturers implement a specific gateway ECU which reads the informations required by the standard from all the suitable places and thru all the required standard, complying with internal vehicle-brand-specific protocols, and makes all these informations available thru a specific CAN bus to which the tachometer device is connected.
In this way, an FMS compliant digital tachometer devices can be easily connected to any FMS compliant truck. [[http://marco.guardigli.it/2010/10/hacking-your-car.html|Extracted from]]

= Links =
http://marco.guardigli.it/2010/10/hacking-your-car.html

= CAN chips  =
 * MAXIM MAX13050 
 * Microchip MCP2551 line driver
 * Philips PCA82C250 
 * Philips/NXP TJA1054  
 * Texas Instruments SN65HVD234D 3.3V CAN transceiver (Teltonika FM4200)
 * Microchip MCP2515 CAN controller 

= FMS links =
 * http://www.intendia.com/en/digital-tacographs/technical/fms-10
 * http://tucrrc.utulsa.edu/DecodingDataDumpIDs.html
 * http://tucrrc.utulsa.edu/J1939.html