CAN is Little endian or big

[ep.hobbyiest]

hi,
CAN is little endian or big endian?

 

[Surender Reddy]

CAN is communication protocol where as Endianness comes with processor architecture.

How can we say CAN is little or big endian?
Both are different.....

 

[FvM]

The basic CAN specification defines a byte transport without an explicite byte order.

There are application layers on top of the CAN protocol, e.g. CANopen/CiA (CAN in automation), refer to the particular specifications.

 

[ep.hobbyiest]

i meant to say if i want to send 4 bytes then byte0 will send first or byte3?

 

[bigdogguru]

Reference: Bosch CAN 2.0 A & B Specifications, Section: PARTA, Data Frame, Data Field, Page: 13

DATA FIELD
The DATA FIELD consists of the data to be transferred within a DATA FRAME. It can
contain from 0 to 8 bytes, which each contain 8 bits which are transferred MSB first.

I have included the following URLs for the Bosch, CiA CAN 2.0 Part A & B Specifications for your convenience.

BOSCH CAN Specification Version 2.0

CiA CAN protocol specification

BigDog

 

[bigdogguru]

It should noted, the CAN 2.0 A/B specification (ISO 11898) makes no reference to the endianness of the underlying architecture of the device for which CAN has been implemented, as the previous two members have indicated. The CAN 2.0 A/B provide only a baseline protocol of the ISO/OSI layer model, layers 1 and 2, by which to implement an overlying protocol, layer 7 (application layer), such as CANopen, DeviceNET, J1939, etc.


BigDog