CAN Bus Guide

CAN Bus Guide – Data Rate And Message Frequency

A Comprehensible Guide to Controller Area Network (CAN Bus) by Wilfried Voss
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A maximum CAN baud rate of 1 MBit/sec may not sound much, but the combination of very short messages, the very effective collision avoidance, error detection and fault confinement capabilities, makes CAN much more suitable for real-time applications than, for instance, TCP/IP with its up to 100 MBit/sec transmission speed. After all, CAN was designed for real-time control, while TCP/IP was designed for data transfer where exact timing is not mandatory.

The maximum number of CAN messages per second is 8,771 (at 1 MBit/sec, 8 bytes per message), up to 17,543 at 1 MBit/sec and 1 byte per message (average bit stuffing applied, see also Chapter 7.2 - Bit Stuffing). This results in a data transfer between 17,543 and 70,168 data bytes per second (Net data transfer, without protocol overhead).