SPRUI30H November 2015 – May 2024 DRA745 , DRA746 , DRA750 , DRA756
The whole message RAM should be configured before the end of the initialization, however it is also possible to change the configuration of message objects during CAN communication.
The CAN software driver must offer subroutines that:
Parameters of the subroutines are the Message Number and a pointer to a complete message structure or to the data bytes of a message structure.
Two examples of assigning the IFx interface register sets to these subroutines are shown here:
In the first method, the tasks of the application program that may access the module are divided into two groups. Each group is restricted to the use of one of the interface register sets. The tasks of one group may interrupt tasks of the other group, but not of the same group.
In the second method, which may be a special case of the first method, there are only two tasks in the application program that access the module. A Read_Message task that uses IF2 or IF3 to get received messages from the message RAM and a Write_Message task that uses IF1 to write messages to be transmitted (or to be configured) into the message RAM. Both tasks may interrupt each other.