CC1354P10: how to change the scifStartRtcTicksNow() RTC tick rate inside the TI Sensor Code Studio GUI vs C code changes in the main application

Hi Chris, 

I am not sure it can be done, but I will ask around.

For testing however, one can set the task iteration interval in SCS:

Regards,

Arthur

Hi Chris

When

scifStartRtcTicksNow(0x00010000 / 100);

the SC will always wake up at a rate of 10 ms, but it will only execute its code every 100 ms, given

fwScheduleTask(10);

is set in the execution code in SCS.

Consider this execution code:

for (U16 n = 0; n < 50; n++) {
gpioToggleOutput(AUXIO_O_SC_OUTPUT_PIN);
fwDelayUs(10);
}

// Schedule the next execution
fwScheduleTask(10);

Looking at the current profile, you will see that the SC wakes up every 10 ms (for a very short period of time), but that the code is executed only every 10^th wake (100 ms)

If the current contribution of waking up every 10 ms is too big, you will need to wake up the main controller and change the interval from the application.

This will increase your current consumption when switching interval since you need to wake up the main CPU, but decrease the current draw from the SC since it sleeps longer.

You can wake up the MCU using

fwGenAlertInterrupt();

and then change the wakeup interval in the scTaskAlertCallback

Below is the current profile, when changing the wakeup interval to 20 ms (from 10) every 5th time the scTaskAlertCallback was called:

static uint8_t count = 0;

void scTaskAlertCallback(void)
{
    // Clear the ALERT interrupt source
    scifClearAlertIntSource();

    // Acknowledge the ALERT event
    scifAckAlertEvents();

    count++;

    if(count == 5)
    {
        count = 0;
        scifStartRtcTicksNow(0x00010000 / 50); // sensor controller runs every 20 ms
    }
    else
    {
        scifStartRtcTicksNow(0x00010000 / 100); // sensor controller runs every 10 ms
    }
}

It is not possible to change the RTC wakeup from the CS

An alternative is to wake up on something other than the RTC. Have the RTC interval set to 100 ms, and then use a timer in the SC set up an interval every 10 ms and use the Timer 0 Event Trigger to have some event code execute at this rate when needed.

BR

Siri