topic Re: MPC5744P reset escalation in MPC5xxx

MPC5744P reset escalation

VladiKn — Tue, 16 Mar 2021 08:20:38 GMT

Hello,

While trying to setup the Online BIST I managed to input a wrong clock divider (I used an even value instead of odd) and now my board entered reset escalation. After that I wasn't able to connect with the debugger anymore. Is it possible to get out of that state now, and how?
On the other hand, is it possible that it's really that easy to kill the microcontroller with one bad write to a register?

Cheers,
Vladimir

Re: MPC5744P reset escalation

davidtosenovjan — Tue, 16 Mar 2021 09:17:15 GMT

Hi, The solution is to stop the core just after power-on-reset, attach by debugger and erase MCU/reload the code.
With TRACE32 it can be done by “Halt core at power-on reset” feature (Select in the menu: MPC5XXX - Tools - Halt core at power-on reset.).

It can be done with PeMicro as well, but procedure is no so simple. Which debugger you are using?

You cannot bricked out the MCU by simple register write, it would have to be some NVM programming as DCF records.

Re: MPC5744P reset escalation

VladiKn — Tue, 16 Mar 2021 09:47:10 GMT

Hi,

Thanks for the quick response. Currently I am using PEMicro. Do you have an example how to do it?
In the MC_CGM_SC_DC0 register I put a value of 0x4 in the DIV field and my application crashed. After that I was no longer able to connect to the board. So I don't know what else could it be.

Re: MPC5744P reset escalation

davidtosenovjan — Tue, 16 Mar 2021 10:12:47 GMT

Actually with S32DS it may be pretty simple to connect:

https://community.nxp.com/t5/MPC5xxx/MPC5748G-Reset-escalation-PEMicro-Multilink-FX/m-p/951223#M14328

Check following thread

Re: MPC5744P reset escalation

VladiKn — Tue, 16 Mar 2021 12:43:46 GMT

Sorry I gave you the wrong information. Actually I use the OpenSDA port for debugging.

Re: MPC5744P reset escalation

davidtosenovjan — Wed, 17 Mar 2021 13:03:22 GMT

I believe in this context it should be pretty much the same.