How the S32K144 FlexCAN Message Buffers divide the receiving and sending region

[JihongZhang]

Hi,

I am developing a FlexCAN driver.For the division of MB receiving and sending region, I have not found a detailed description document. Where can I find it

[Joey_van_Hummel · Accepted solution]

Sending and receiving region is user defined by the CODE field of the message buffer.

[PetrS]

Hi,

you should get most of the info directly from the device Reference Manual, in FlexCAN chapter.
The FlexCAN module uses a very flexible mailbox system for transmitting and receiving CAN frames. The mailbox system is composed of a set of message buffers (MB) that store configuration and control data, time stamp, message ID, and data/payload (see chapter 55.5.3 Message buffer structure).
S32K144 offers up to 32MBs (assuming 8byte payload) which can be configured individually for TX or RX operation. When CAN FD is enabled, the exact address for each MB depends on the size of its payload. See chapter 55.5.4 and 55.5.5 for FlexCAN memory partition and MBs memory map.
A process of transmission resp. reception is described in chapters 55.3.2-55.3.3 resp. 55.3.4-55.3.5.

BR, Petr