S32K310 CAN MessageBuffer and HwObjectCount

Embedded_novice — Wed, 19 Feb 2025 08:36:40 GMT

我在使用EB配置S32K310的MCAL的CAN模块时产生一些疑问：

1.我在手册中看到S32K310的MessageBuffer大小是64，那么HwObjectCount的最大配置数是否与MessageBuffer相关，如果不相关的话，我想知道HwObjectCount的最大配置数收什么因素的限制？MessageBuffer的最大个数64又会影响什么配置？（在我个人的理解中，FIFO的大小应该是由HwObjectCount决定的，且HwObjectCount不应该超过MessageBuffer的大小）

2.CAN模块是否一定要搭配CANIF组件使用，MailBox是在使用CANIF时才会用到的概念吗？MailBox的大小与什么有关？

感谢帮助！

Re: S32K310 CAN MessageBuffer and HwObjectCount

Julián_AragónM — Fri, 21 Feb 2025 18:59:07 GMT

Hi @Embedded_novice,

According to the FlexCAN MCAL user manual, in case of HRH, HwObjectCount is number of
elements in the hardware FIFO.

Regarding your question, yes, CAN hardware objects defined as a PDU buffer. The CAN RAM block can store message buffers in different configurations of sizes. According to the S32K3XX reference manual, the RAM block can store 32 messages of 8 bytes, 21 messages of 16 bytes, 12 messages of 32 bytes or 7 messages of 64 bytes. So, it is based on MB.

The CAN Interface (CanIf) is found between the low-level CAN drivers and the upper communication service layers from the AUTOSAR stack. It is not related to the Mailbox concept. The mailbox system is composed of a set of message buffers (MB) that store configuration and control data, time stamp, message ID, and data (see Message buffer structure).

You can read the following article to know more about the CAN module: Communicating over the CAN Bus - NXP Community.

Hope this helps.

topic Re: S32K310 CAN MessageBuffer and HwObjectCount in S32K

S32K310 CAN MessageBuffer and HwObjectCount

Re: S32K310 CAN MessageBuffer and HwObjectCount