mm9z1-638:How to prevent system crashing after entering stop mode.

[gumu]

Dear Sir,

I'd like to ask a question, after the system enters the stop mode and the COP is disabled, if the system crashes in this state, how can it be recovered and is there any way to solve this scenario?

[Q_man]

Hi Mu, the device always wakes up if enabled and in low power mode (LP). If you observe issue its best to find the root cause.

The watchdog can not recover from LP as its always idle in LP.

[Q_man]

Hi Mu, the wakeup should always work if enabled! If you observe strange behaviour it's best to first check any wrong configuration / sw issues!

If the device is in low power mode, then the watchdog can not help, e.g. if you have all wakeup sources disabled and enter low power mode the device will require a power cycle to recover.

[Q_man · Accepted solution]

Hi Mu,

if the system (analog die) can be woken up (e.g. LIN, after Timeout, PTB4, etc.) I suggest to use the watchdog timer on the analog die (must be enabled before entering stop!

See https://community.nxp.com/t5/S12-MagniV-Microcontrollers/COP-and-analog-die-watchdog-usage/td-p/1700...

W.

[gumu]

Hi @Q_man ，

In practical testing, I found that the device cannot be woken up with PTB4 after it enters sleep mode. It requires a power cycle to recover. I am wondering if enabling the analog die watchdog can help avoid such a problem? Is there any way to recover?

Thanks!