Using Comparator as "Window" for potentiometer wake up.

[LukeC]

I am trying to use the comparator to wake me up when a potentiometer is moved a certain amount.

Before I sleep I read the ADC value of the comparator and use this to set the upper and lower value of the comparator.

My issue is this only works when I move the POT down.  For some reason the UP direction is not working.

I am including the NRF_DRV_COMP_EVT_EN_UP_MASK in my nrf_drv_comp_start  command.  What else needs to be added to get an event when the voltage crosses the upper threshold?

This is using the nRF52832 , SDK14

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#define COMPTH_MAX 63

#define COMPTH_INTERVAL 5

void zoom_comp_init(void)

{

uint32_t err_code;

nrf_saadc_value_t vdd, adcval;

nrf_drv_comp_uninit();

APP_ERROR_CHECK(nrf_drv_saadc_sample_convert(4, &vdd));

APP_ERROR_CHECK(nrf_drv_saadc_sample_convert(0, &adcval));

// hw_adc_disable();

float frac = (float)adcval / (float)vdd;

// ref_setting = frac*16.0;

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#define COMPTH_MAX 63
#define COMPTH_INTERVAL 5

void zoom_comp_init(void)
{

    uint32_t err_code;

    nrf_saadc_value_t vdd, adcval;

    nrf_drv_comp_uninit();

    APP_ERROR_CHECK(nrf_drv_saadc_sample_convert(4, &vdd));

    APP_ERROR_CHECK(nrf_drv_saadc_sample_convert(0, &adcval));

    // hw_adc_disable();

    float frac = (float)adcval / (float)vdd;

    // ref_setting = frac*16.0;
    static uint8_t myrefval = 0; //(0-16)
    frac *= 64.0;
    myrefval = (uint8_t)frac;
    
    nrf_drv_comp_config_t myCompConfig = NRF_DRV_COMP_DEFAULT_CONFIG(NRF_COMP_INPUT_0);

    myCompConfig.input = NRF_COMP_INPUT_0;
    myCompConfig.main_mode = NRF_COMP_MAIN_MODE_SE;
    myCompConfig.reference = NRF_COMP_REF_VDD;
    myCompConfig.speed_mode = NRF_COMP_SP_MODE_Normal;
    //myCompConfig.hyst = NRF_COMP_HYST_50mV;
    myCompConfig.isource = COMP_ISOURCE_ISOURCE_Off;
    myCompConfig.interrupt_priority = 6;

    if (myrefval > (COMPTH_MAX - COMPTH_INTERVAL) )
    {
	myCompConfig.threshold.th_down = COMPTH_MAX - COMPTH_INTERVAL*2;
	myCompConfig.threshold.th_up = COMPTH_MAX;
    }
    else if (myrefval < COMPTH_INTERVAL)
    {
	myCompConfig.threshold.th_down = 0;
	myCompConfig.threshold.th_up = COMPTH_INTERVAL*2;
    }
    else
    {
	myCompConfig.threshold.th_down = myrefval - COMPTH_INTERVAL;
	myCompConfig.threshold.th_up = myrefval + COMPTH_INTERVAL;
    }

    NRF_LOG_INFO("ZOOM |  Reference Value=%d", myrefval);
    NRF_LOG_INFO("ZOOM |  TH_DOWN=%d  TH_UP=%d", myCompConfig.threshold.th_down, myCompConfig.threshold.th_up);

    err_code = nrf_drv_comp_init(&myCompConfig, comp_event_handler);
    APP_ERROR_CHECK(err_code);

    nrf_drv_comp_start( NRF_DRV_COMP_EVT_EN_DOWN_MASK | NRF_DRV_COMP_EVT_EN_UP_MASK ,
        NRF_DRV_COMP_SHORT_STOP_AFTER_UP_EVT | NRF_DRV_COMP_SHORT_STOP_AFTER_DOWN_EVT | NRF_DRV_COMP_SHORT_STOP_AFTER_CROSS_EVT);

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static void comp_event_handler(nrf_comp_event_t event)

{

asm("nop;");

NRF_LOG_INFO("Comp Event.");

switch (event)

{

case NRF_COMP_EVENT_CROSS:

NRF_LOG_INFO("Comp CROSS Event.");

sysEvents.zoom_change = 1;

break;

case NRF_COMP_EVENT_DOWN:

// sysEvents.zoom_change = 1;

//if (update_zoom())

{

NRF_LOG_INFO("Comp DOWN Event.");

sysEvents.zoom_change = 1;

}

break;

case NRF_COMP_EVENT_UP:

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static void comp_event_handler(nrf_comp_event_t event)
{

    asm("nop;");
    NRF_LOG_INFO("Comp Event.");
    switch (event)
    {
	case NRF_COMP_EVENT_CROSS:
	    NRF_LOG_INFO("Comp CROSS Event.");
	    sysEvents.zoom_change = 1;
	    break;
	case NRF_COMP_EVENT_DOWN:

	    // sysEvents.zoom_change = 1;
	    //if (update_zoom())
	    {
		NRF_LOG_INFO("Comp DOWN Event.");
		sysEvents.zoom_change = 1;
	    }
	    break;
	case NRF_COMP_EVENT_UP:

	    //if (update_zoom())
	    {
		NRF_LOG_INFO("Comp UP Event.");
		sysEvents.zoom_change = 1;
	    }
	    // sysEvents.zoom_change = 1;
	    break;
    }
}