Rainbow Electronics NUC140 - Manual (Page 49)

NUC140 Series DATA SHEET
Publication Release Date: May 31, 2010
- 49 - Revision V1.02
5.13 Controller Area Network (CAN Bus)
5.13.1 Introduction
The Controller Area Network (CAN) is a serial communications protocol which is multi-master and it
efficiently supports distributed real-time control with very high level of security. Its domain of
application range from high speed networks to low cost multiplex wiring. In automotive electronics,
engine control units, sensors, anti-skid-systems, etc. are connected using CAN with bit-rates up to
1Mbit/s.
In CAN systems, a node does not make use of any information about the system configuration (station
addresses). Any Nodes can be added to the CAN network without requiring any change in the
software or hardware of any node. The information on the bus is sent in fixed format message of
different but limited length. When the bus is free, any connected unit may start to transmit a new
message. The content of message is named by IDENTIFIER. The IDENTIFIER does not indicate the
destination of the message, but describes the meaning of the data, so that all nodes in the network are
able to decide by Message Filtering whether the data is to be acted upon by them or not. Within a
CAN network it is guaranteed that a message is simultaneously accepted either by all nodes or by no
node.
5.13.2 Features
z CAN 2.0B protocol compatibility
z AMBA APB bus interface compatible
z Multi-master node
z Support 11-bit identifier as well as 29-bit identifier
z Bit rates up to 1Mbits/s
z NRZ bit coding
z Error detection: bit error, stuff error, form error, 15-bit CRC detection, and acknowledge error
z Listen only mode (no acknowledge, no active error flags)
z Acceptance filter extension (4-byte code, 4-byte mask)
z Error interrupt for each CAN-bus error
z Extended receive buffer (8-byte FIFO)
z Wakeup function