RE: HX711 with ANT bpwr profile

Vidar Berg — Mon, 16 Dec 2019 15:49:51 GMT

Hi,

It shouldn't be necessary to initialize it before the Softdevice. I think you will need to debug the app if you want to find out why it's required in your case.

[quote user="Pepam"]I have one last question. Please, could you provide me some link, where i can find and learn more about these lines of code about timer and its compare registers that you used in your library?[/quote]

I used PPI, GPIOTE, and TIMER for this so I think you may find the following links helpful:

- GPIOTE

- PPI — Programmable peripheral interconnect

- TIMER — Timer/counter

RE: HX711 with ANT bpwr profile

Pepam — Mon, 16 Dec 2019 14:54:09 GMT

Hi,

Solved it by moving hx711_init() and hx711_start() to the beginning of main function before code lines that handles start of softdevice and profile initiation.

And yes, i am testing it on nRF52832 DK and when i wrote hx711_start(true) it didn`t work too. But now, when it is placed before softdevice and profile initiation it works.

I have one last question. Please, could you provide me some link, where i can find and learn more about these lines of code about timer and its compare registers that you used in your library?

Thanks for answer,

Pepam

static void hx711_sample()
{
    NRF_TIMER2->TASKS_CLEAR = 1;
    m_sample.count = 0;
    m_sample.value = 0;
    NRF_TIMER1->TASKS_START = 1; // Starts clock signal on PD_SCK

    for (uint32_t i=0; i < ADC_RES; i++)
    {
        do
        {
            /* NRF_TIMER->CC[1] contains number of clock cycles.*/
            NRF_TIMER2->TASKS_CAPTURE[1] = 1;
            if (NRF_TIMER2->CC[1] >= ADC_RES) goto EXIT; // Readout not in sync with PD_CLK. Abort and notify error.
        }
        while(NRF_TIMER1->EVENTS_COMPARE[0] == 0);
        NRF_TIMER1->EVENTS_COMPARE[0] = 0;
        m_sample.value |= (nrf_gpio_pin_read(DOUT) << (23 - i));
        m_sample.count++;
    }
    EXIT:

    if (!m_continous_sampling)
    {
        NRF_GPIOTE->TASKS_SET[1] = 1; // HX711 power-down
    }
    
    
    /*and also this part of Your code==========================================*/
      
      NRF_TIMER1->CC[0]     = 1;
  NRF_TIMER1->CC[1]     = TIMER_COMPARE;
  NRF_TIMER1->CC[2]     = TIMER_COUNTERTOP;
  NRF_TIMER1->SHORTS    = (uint32_t) (1 << 2);    //COMPARE2_CLEAR
  NRF_TIMER1->PRESCALER = 0;

  NRF_TIMER2->CC[0]     = m_mode;
  NRF_TIMER2->MODE      = 2;

  NRF_GPIOTE->CONFIG[1] = (uint32_t) (3 | (PD_SCK << 8) | (1 << 16) | (1 << 20));

  NRF_PPI->CH[0].EEP   = (uint32_t) &NRF_TIMER1->EVENTS_COMPARE[0];
  NRF_PPI->CH[0].TEP   = (uint32_t) &NRF_GPIOTE->TASKS_SET[1];
  NRF_PPI->CH[1].EEP   = (uint32_t) &NRF_TIMER1->EVENTS_COMPARE[1];
  NRF_PPI->CH[1].TEP   = (uint32_t) &NRF_GPIOTE->TASKS_CLR[1];
  NRF_PPI->FORK[1].TEP = (uint32_t) &NRF_TIMER2->TASKS_COUNT; // Increment on falling edge
  NRF_PPI->CH[2].EEP   = (uint32_t) &NRF_TIMER2->EVENTS_COMPARE[0];
  NRF_PPI->CH[2].TEP   = (uint32_t) &NRF_TIMER1->TASKS_SHUTDOWN;
  NRF_PPI->CHEN = 7;
}

RE: HX711 with ANT bpwr profile

Vidar Berg — Mon, 16 Dec 2019 13:52:41 GMT

Hi,

Are you testing this on a Nordic DK? I'm wondering if maybe the continuous sampling interferes with the radio. Please try and see if it works if you only call hx711_start(true) once.

Thanks,

Vidar