Setting the timeout value in the RTWDOG on NXP RT 1020

[ikuzmych]

Hello,

I am very new to using the NXP RT 1020 and am responsible for developing a watchdog timer for a CubeSat. Right now I am in the process of setting up the rtwdog and am unsure of what to set the timeout value to. I could not find the clock speed in the documentation for the bus clock and am unsure what to set the timeout value to in the register if I want it to be one minute. What should I put the RTWDOG_TOVAL to in order to make the timeout value 1 minute?

[ikuzmych]

OK thank you. Also, when following the code examples in the documenation, when setting something to the CS register, do I do WDOG_CS = ... or RTWDOG_CS... Sorry, I just am pretty new to embedded systems work, specifically with this hardware.

[kerryzhou]

Hi @ikuzmych ，

  In fact, it is very easy.

1. know the clock source

2. then do the prescaler, then calculate your needed timeout value.

3. About the code, you can refer to the SDK:

SDK_2_11_0_EVK-MIMXRT1020\boards\evkmimxrt1020\driver_examples\rtwdog

More details, read the RT1020RM,Chapter 53 RTWDOG (WDOG3), you will be more clearly.

Wish it helps you!

Best Regards,

kerry