S32k144 CAN cell stops working

[gpira]

Hi everyone,

I am conducting some EMC test in one of my applications which uses the S32K144 LQFP64 (FS32K144HFT0VLHT).

During the BCI test, the CAN cell stops working. It can't receive, neither transmit anything. Even after the perturbation ends, the problem persists and it can be solve only by resetting the ECU. The microcontroller instead is still alive and continues with its normal operations. 

At first I thought it was stuck into BUS OFF state, but after I have run some test I can confirm that this is not the case. (I have forced it into BUSOFF and I have observed that the cell is able to automatically recover from this error condition and resume its normal behaviour as soon as the perturbation ends).

I have also tried to reset the transceiver, but the problem persisted.

It seems that the cell goes into some mode where it cuts off all communication, while the rest of the micro continues to work properly. I thought it went into freeze mode and tried to force it out but I got no results.
Could it be some kind of protection kicking in? Have you heard from anyone with this problem before, and do you know if there is any strategy to solve it?

Thanks,

Giacomo

[PetrS]

Hi,

I am not aware there should be such kind of issue with the module. Try to check module registers and MB area if there are values not expected, if any errors are detected etc. Or share registers and MBs content.
Be sure pins connected to CAN transceiver are still configured for CAN functionality and transceiver is active. Also check if module and PE clocks are active.
You can try to do module software reset.
BTW do you use any kind of drivers (SDK, RTD, etc.) or have own written baremetal code? 

BR, Petr

[gpira]

Hi Petr,

thanks for your quick reply.

I'll try to investigate what you have told me, but it will be difficult since I can't replicate this behaviour at my desk, but only in the test chamber, so I can't debug the system when the problem occurs.

In any case, in my application I am using  S32SDK S32K1XX RTM 4.0.2 and S32K1xx development package 3.4.1. and I run the CAN with the FlexCAN Driver.

Best regards,

Giacomo

[PetrS]

Hi,

it could be SW issue too. For SDK I can suggest to check internal driver status variable as well. 
But without debugging the MCU finding root cause will be quite hard.

BR, Petr