I would like to use the capsense example with a Bluetooth application. But as it's not compatible with softdevice, I want to modify it. Two questions:
1 – As anyone already done it?
If not, I would like to use handler function instead of PPI, but I don’t know how to call a function from an event without nrf_drivers. Because the capsense example use Hardware Access Layer.
2 – How do I set a callback function from a comparator event in HAL? Or do I need to rewrite all the example and use the drivers functions?
I tried to replace this :
static void config_ppi(void)
{
// Use PPI to start timer at upward crossing
NRF_PPI->CH[CAPSENSE_PPI_CH0].EEP = (uint32_t)&NRF_COMP->EVENTS_UP;
NRF_PPI->CH[CAPSENSE_PPI_CH0].TEP = (uint32_t)&CAPSENSE_TIMER->TASKS_START;
NRF_PPI->CHENSET = 1 << CAPSENSE_PPI_CH0;
// Use PPI to capture timer at downward crossing to CC[0] and stop
// the timer
NRF_PPI->CH[CAPSENSE_PPI_CH1].EEP = (uint32_t)&NRF_COMP->EVENTS_DOWN;
NRF_PPI->CH[CAPSENSE_PPI_CH1].TEP = (uint32_t)&CAPSENSE_TIMER->TASKS_CAPTURE[0];
NRF_PPI->FORK[CAPSENSE_PPI_CH1].TEP = (uint32_t)&CAPSENSE_TIMER->TASKS_STOP;
NRF_PPI->CHENSET = 1 << CAPSENSE_PPI_CH1;
}
with this :
void COMP_LPCOMP_IRQHandler(void)
{
// This interrupt is triggered when a sample has been
// collected. The "sample" is the half period of the oscillator
// (which is depandent of the capacitance of the sensor).
if(NRF_COMP->EVENTS_UP)
{
NRF_COMP->EVENTS_UP = 0;
CAPSENSE_TIMER->TASKS_START = 1;
}
if (NRF_COMP->EVENTS_DOWN)
{
CAPSENSE_TIMER->TASKS_CAPTURE[0] = 1;
CAPSENSE_TIMER->TASKS_STOP = 1;
NRF_COMP->EVENTS_DOWN = 0;
if (m_calibration_active)
{
calibration_sample_finalize();
}
else
{
sample_finalize();
}
CAPSENSE_TIMER->TASKS_START = 0;
CAPSENSE_TIMER->TASKS_CAPTURE[0] = 0;
CAPSENSE_TIMER->TASKS_STOP = 0;
}
}
But it doesn't work.
