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Mixed can message id length on same bus

Chuck 3 years ago in IQANdesign updated by Gustav Widén (System support) 3 years ago 3

For generic busses, I would like to suggest the ability to specify message Identifier Size (11 or 29bit) on each message rather than the entire bus.

It is possible to mix 11 and 29 bit identifiers on the same physical bus, the way this is done is by using two Generic bus symbols in the system layout with matching bus-speed, connected to the same CAN port on the master module. 


Since the generic bus is automatically added in version 5 when connecting a generic module, the way you create this is by first connecting the modules to two separate ports, to get two separate bus symbols, then change the identifier size, and then move them to the same port. 

Is it necessary to specify the identifier length at the bus level?  Can the software know based on the GFIN and GFOUT identifier definitions and the module assignments?

Yes, the bus component in the system layout has the property for the identifier size, and the assignment of the modules to the bus associates this property with the GFIN:s.