S32KのトピックRe: LIN slave wakeup issue

LIN slave wakeup issue

Pavani — Wed, 27 Apr 2022 11:09:54 GMT

Hello,

I am working on s32k116 controller and using LIN stack from NXP. Our device is configured as slave.

If Master and slave are powered ON simultaneously and communication starts, Slave is responding properly.

But, If slave is powered ON and Master is in sleep mode. Our slave goes to sleep after 4 seconds(timeout), Now, If we start the transmission from master, slave is not responding. If we start the transmission within 4 seconds then slave is responding as expected.

while debugging we observed that autobaud capturing is not successful in the issue scenario.

Re: LIN slave wakeup issue

PetrS — Wed, 04 May 2022 10:04:12 GMT

Hi,

please see below a feedback I got from Apps team...

Q: But, If slave is powered ON and Master is in sleep mode. Our slave goes to sleep after 4 seconds(timeout), Now, If we start the transmission from master, slave is not responding. If we start the transmission within 4 seconds then slave is responding as expected.

[Diep] According to the lin spec, because the slave node goes to sleep mode, so the master node must send a wake-up signal before sending any frames on the bus.

Please refer chapter 2.6 of LIN_Specification_Package_2.2A.pdf for more detail.

If the issue is still not resolved, please share your project and then I will try to check on my site.

BR, Petr

Re: LIN slave wakeup issue

Pavani — Wed, 04 May 2022 10:22:07 GMT

Hello,

while debugging I have observed that autobaud calculations are not done properly. so I disabled autobaud in LIN stack component. Now all the conditions which I mentioned above are working fine.

According to the lin spec, because the slave node goes to sleep mode, so the master node must send a wake-up signal before sending any frames on the bus. ->one more doubt, isn't running the schedule table in LIN master(which starts transmitting the frames) wakeup slave when it is in sleep mode?

Re: LIN slave wakeup issue

PetrS — Thu, 05 May 2022 06:56:48 GMT

Hi,

below is feedback i got...

In some cases, when slave node is in sleep mode, it still can receive the break field as wake-up signal and then receive the frames from the master node normally. However, I recommend that master node should send a wakeup signal in this case.

BR, Petr