After SWT_CR.WEN is set to 1, board does reset few times and stuck. Cannot be flashed anymore.

[mikiB]

Hello,

I am using DevKIT - MPC5748G.
Testing by using NXP S32 design studio.

Accidentally I changed SWT_CR.WEN and enabled WDG.
Now every time I power the board reset happens few time and board stuck with reset red diode on.
I cannot flash code to disable WDG, as board is in constant reset, so my board now is useless. 

Is there some other way to disable WDG, so I can flash new code and change SWT_CR.WEN to 0.

[lukaszadrapa · Accepted solution]

Hi Milan,

please take a look at this thread:

https://community.nxp.com/t5/MPC5xxx/MPC5748G-Cannot-attached-JTAG-after-erase-all/m-p/617380

Peter Vranken thoroughly explains his experience how to recover.

If your SWT timeout is long enough (longer than the default one), you could be able to OpenSDA. If not, it's necessary to use another debug probe like Pemicro Multilink or Lauterbach.

Regards,

Lukas