Set Init = 1
Set CCE = 1
Wait for Init =1
Write Bit timing values into BTR
Clear CCE and Init
Wait for Init =0
CCE = 0 , Init =0
Normal Mode
Initialization Mode
Normal Mode
CAN Module Configuration
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SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Controller Area Network (DCAN) Module
23.4 CAN Module Configuration
After a hardware reset all CAN protocol functions are disabled. The CAN module must be initialized and
configured before it can participate on the CAN bus.
23.4.1 DCAN RAM Initialization through Hardware
To start with a clean DCAN RAM ,the complete DCAN RAM can be initialized with zeros and the
ecc/parity bits set accordingly by configuring the following registers in the system module:
1. Memory Hardware Initialization Global Control Register (MINITGCR)
2. Memory Initialization Enable Register (MSINENA)
For more details on RAM hardware initialization support, refer to the system module reference guide.
23.4.2 CAN Module Initialization
To initialize the CAN Controller, you have to set up the CAN Bit timing and those message objects that
have to be used for CAN communication. Message objects that are not needed, can be deactivated.
So the two critical steps are:
1. Configuration of CAN Bit Timings
2. Configuration of Message Objects
23.4.2.1 Software Configuration of CAN Bit Timings
This step involves configuring the CAN baud rate register with the calculated CAN bit timing value. The
calculation procedure of CAN bit timing values for BTR register are mentioned in
. Refer to
for CAN bit timing software configuration flow.
Figure 23-3. CAN Bit-timing Configuration