What does Software Watchdog & Hardware Watchdog means in the K series?

[trannamson]

Dear community members,

I'm working with the Kinetis K series Product Update Report (KPUR). There are two kinds of watchdog is written : Software Watchdog and Hardware Watchdog.

However when I check out the Reference Manual such as MK70FX512VMJ15, There are two kinds of watchdog in different name : External watchdog monitor (EWM) and Software watchdog (WDOG).
I consider External watchdog monitor (EWM) is the Hardware Watchdog which is written in KPUR but I'm confuse if it was correct or not.

Does anyone give me a lecture to clearly understand about this?
Thank you!

[Kan_Li]

Hi Nam,

In my understanding, EWM is used to monitor the enternal peripheral while WDOG is used to monitor the embedded software flow and execution, the main difference between them is EWM does not reset the MCU's CPU and on-chip peripherals, it has an independent pin to assert reset or place an external circuit into safe mode when EWM is allowed to time-out.

Hope that makes sense,

Have a great day,
Kan

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[trannamson]

Hi Kan,

Thank you for pointing out the difference between EWM and WDOG. I've checked the Reference manual and get what you mean.
But what I confuse is the meaning of Hardware Watchdog. And how difference between Hardware Watchdog and Software Watchdog?

Thank you and have a great day,

Tran.

[Kan_Li]

Hi Tran,

In my understanding, they are both hardware modules on the chip, the main difference is their usage, EWM usually monitors the external hardware, while WDOG monitors the embedded software.

Have a great day,
Kan

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Note: If this post answers your question, please click the Correct Answer button. Thank you!
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[trannamson]

Hi Kan,

Thank you for your advise!

Best Regard

Tran.