How do I modify the grblHAl to implement CAN bus communication between multiple development boards?

[mr-huang-mou]

I want to burn grblHAL on one development board, which can receive/send data to the CAN bus, and the other two boards are responsible for sending/receiving data from the CAN bus.
My ultimate goal is to realize the operation of other mechanisms before the three-axis mechanism moves, and after other mechanisms have realized their own functions, send instructions to the CAN bus to notify the grblHAL development board that it can perform the movement task.