GPIO and COMP strange behavior

RE: GPIO and COMP strange behavior

Jared — Wed, 05 Jun 2019 13:04:38 GMT

Hi,

The issue can be related to this errata. Could you try using the LPCOMP instead and see if you experience the same issue? Also, notice this errata regarding LPCOMP.

Regards

Jared

RE: GPIO and COMP strange behavior

BartoszT — Fri, 31 May 2019 10:55:01 GMT

Initialization code

    NRF_GPIO->PIN_CNF[4]=0x04;  // INPUT - AnalogInput2
    NRF_GPIO->PIN_CNF[9]=0x03;  // OUTPUT - LED

    NRF_COMP->PSEL=COMP_PSEL_PSEL_AnalogInput2;
    NRF_COMP->MODE=COMP_MODE_MAIN_SE<<COMP_MODE_MAIN_Pos;   
    
    NRF_COMP->REFSEL=COMP_REFSEL_REFSEL_Int1V2<<COMP_REFSEL_REFSEL_Pos;
    NRF_COMP->TH|= (5<<COMP_TH_THDOWN_Pos) | 5<<COMP_TH_THUP_Pos;
    NRF_COMP->HYST=COMP_HYST_HYST_Hyst50mV;

    NRF_COMP->INTENSET= (COMP_INTEN_UP_Enabled<<COMP_INTEN_UP_Pos) | (COMP_INTEN_DOWN_Enabled<<COMP_INTEN_DOWN_Pos);

    NRF_COMP->ENABLE=COMP_ENABLE_ENABLE_Enabled;

    NVIC_SetPriority( COMP_LPCOMP_IRQn, 0 );
	NVIC_ClearPendingIRQ( COMP_LPCOMP_IRQn );
    NVIC_EnableIRQ(COMP_LPCOMP_IRQn);
		
	NRF_COMP->TASKS_START=1;

Interrupt Code

void COMP_LPCOMP_IRQHandler(void)
{
	NVIC_ClearPendingIRQ( COMP_LPCOMP_IRQn );

	NRF_COMP->EVENTS_READY=0;
	NRF_COMP->EVENTS_DOWN=0;
	NRF_COMP->EVENTS_UP=0;
	NRF_COMP->EVENTS_CROSS=0;


	if(NRF_COMP->RESULT==1)
	NRF_GPIO->OUTCLR=1<<9;
	else
	NRF_GPIO->OUTSET=1<<9;

}

RE: GPIO and COMP strange behavior

Jared — Fri, 31 May 2019 10:05:58 GMT

Hi,

Are you using the COMP in differential or in signal ended mode? What are you using as a reference voltage? Could you share the code that you're using to sense the signal change?

Regards

Jared