Re: PLL change

Hi,

I also need to be able to generate a controlled reset in order to
perform a reboot.

The way I achieve it is this :-

After a power-on reset, I set he CSR bit set in the PLPRCR register 
and the ME bit set in the MSR.

In this configuration, If an illegal address is accessed then it is 
trapped by the machine check exception.

Then, when I want to generate a reset, I clear the ME bit in the MSR 
and read or write to an illegal memory location (ie one that is not 
mapped by one of the chip selects).

This then generates a checkstop reset.

This is much more controlled than waiting for a watchdog to time out.

Hope this helps

Mark

--- In [email protected], "qty154" <qty154@y...> wrote:
>
> Hello!
> 
> I want to achieve a board reset on my Wuerz MPC555 board that is 
> initiated from software. I have one option, that is the watchdog. I 
> simply don't update the key register and the watchdog, when 
expired, 
> causes a hard reset. However, watchdog is not always enabled.
> Second trial is to use the clock. I lock the MF, CSRC, LPM fields, 
and 
> I try to change the MF. According to the manual it should cause a 
hard 
> reset (because of the lock). However, nothing such actually happens.
> Before the changes, PLPRCR and SCCR is the following:
> 
> PLPRCR: 0X00915080  SCCR: 0XAD20C040
> 
> After the changes (change MF and set LOLRE) the registers look like 
> this:
> 
> PLPRCR: 0X006150C0  SCCR: 0XAD20C040
> 
> Why doesn't reset the MPC555?
> How can I achieve reset?
> 
> Regards
> Attila
>






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