17-04-2009, 08:18 PM
CAN (Controller area network)
“ Protocol for real-time applications
“ Developed by Robert Bosch GmbH
“ Originally for communication among components of cars
“ Applications now using CAN include:
¢ elevator controllers, copiers, telescopes, production-line control systems, and medical instruments
“ Data transfer rates up to 1 Mbit/s and 11-bit addressing
“ Common devices interfacing with CAN:
¢ 8051-compatible 8592 processor and standalone CAN controllers
“ Actual physical design of CAN bus not specified in protocol
¢ Requires devices to transmit/detect dominant and recessive signals to/from bus
¢ e.g., ˜1™ = dominant, ˜0™ = recessive if single data wire used
¢ Bus guarantees dominant signal prevails over recessive signal if asserted simultaneously