VLLSx on Coldefile+

[nz_developer]

Trying to get a coldfire+ into VLLS3 mode but when I measure the current it is not dropping (3uA according to datasheet. I am at several mA.)

Any Ideas? I call the Sleep function to put into low power mode

void deepsleep (void)

{

/* Set the SLEEPDEEP bit to enable deep sleep mode (STOP) */

    asm (  stop #0x2000; );

}

void Sleep(void){

    u8 dummyread;

    SetAlarm(10); // wake up in 10 seconds

    SetLLWU(); // setup wakeup events

        SMC_PMPROT = SMC_PMPROT_AVLLS_MASK;

         SMC_PMCTRL &= ~SMC_PMCTRL_STOPM_MASK ;

         SMC_PMCTRL |= SMC_PMCTRL_STOPM(0x4) ;

         dummyread = SMC_PMCTRL_STOPM(0x4);

         SMC_VLLSCTRL =  BIT2; 

        /*wait for write to complete to SMC before stopping core */

         dummyread = SMC_VLLSCTRL;

        dummyread = SMC_PMCTRL;

           deepsleep();

}

[Nouchi]

Hello,

You have to take care about unused pins, they must be configured as output, or tied to vdd, because floating pin may draw current.

Emmanuel

[nz_developer]

Hi Thanks,

Can I just set to output low? some of my pins need to be low while in Sleep mode.

Thanks again

[Nouchi]

Yes but, if you have some pull-up on it, it will drawn current, so you have to take to disable internals pull-up and remove external if needed.

[nz_developer]

Tried lots of port configeration settings including disabling all ports etc. Got the current down to 360uA about 100x what I should be getting from the datasheet. Not too easy to solve, I will request support from Freescale through distributor.

[Nouchi]

You have maybe something still powered or clocked.

When you begin to play with micro amps, you have to hunt for leaks.

[nz_developer · Accepted solution]

Found the problem, it was a register to enable stop mode had not been set right. Used Processor expert to setup and that solved it. Got 3uA draw and wake on timer or one of my 3 buttons, very nice.