How to measure and reduce Wake Up time in full stop mode

[vyshakh_j]

Hi All,

I am using MC9S12ZVLA128 controller for my application, and I am using the full stop mode feature of the MCU,

and I am getting current consumption of around 30uA, but my wake time is too large around 200ms.

Not sure , whether it is an issue with my measurement or do I need to make any configuration to reduce the wake up time in full stop mode.

I am running my system with an external oscillator of 10Mhz and PLL clock is derived from this external oscillator and system clock has been derived from PLL clock(64Mhz).

Can you suggest a method for measuring the wake up time ? and how can I reduce my wake up time as low as possible in full stop mode.

Regards,

Vyshakh J

[lama]

Hi,

could you please provide/share simplified C code where you only show:

clock setup, wake up peripheral setup, wake up clock repair procedure (PLLSEL is automatically cleared going into stop mode ), stop mode enter procedure, wake up measurement. The easiest is to wake up on some edge event on selected port and then to perform change of the level on another port when PLL is locked back to required value. Of course, wake up is finished sooner when the mcu starts to work but it is interesting to get time when the MCU is prepared to work under required clock conditions.  (Or you can select another event to think the MCU is woken up....before pll refreshment...its up to you....what do you prefer?)

I'll check and test it.

Best regards,

Ladislav