nRF52 Uart

[Allen96]

Hi,

i'm actually working for interface the nRF52 with the STM32. Actually i completed the part where the STM32 send some data and the nRF52 recive it.

Now i need to do the same thing but with the nRF52 that send the data. I put an oscilloscope to see the data and nothing seems to happen. I'm not really understanding what can be the mistake.

Here's my code for set the uart:

void USART_Set(){

    uint32_t err_code;

    nrf_gpio_cfg_input(UART_RX_PIN, NRF_GPIO_PIN_PULLUP);
    nrf_gpio_cfg_output(UART_TX_PIN);

    const app_uart_comm_params_t comm_params =
      {
          UART_RX_PIN,
          UART_TX_PIN,
          RTS_PIN_NUMBER,
          CTS_PIN_NUMBER,
          APP_UART_FLOW_CONTROL_DISABLED,
          false,
          UART_BAUDRATE_BAUDRATE_Baud9600
      };

    APP_UART_FIFO_INIT(&comm_params,
                         UART_RX_BUF_SIZE,
                         UART_TX_BUF_SIZE,
                         uart_evt_callback,
                         APP_IRQ_PRIORITY_HIGHEST,
                         err_code);

    APP_ERROR_CHECK(err_code);
}

#define UART_TX_PIN 9 //31
#define UART_RX_PIN 11 //30

#define UART_CTS_PIN 7
#define UART_RTS_PIN 8

Then i do:

int main(void)
{
    uint32_t err_code;

    timers_init();
    ...
    advertising_start(erase_bonds);




    USART_Set();

    tx_enable = 1;
    err_code = app_uart_put(0xAA);
    APP_ERROR_CHECK(err_code);

    // Enter main loop.
    while(1){
        ...
    }
}

and inside the handler:

void uart_evt_callback(app_uart_evt_t * p_event)
{
    uint32_t err_code;

    if (p_event->evt_type == APP_UART_FIFO_ERROR || p_event->evt_type == APP_UART_COMMUNICATION_ERROR)
    {
        err_code = app_uart_flush();
        APP_ERROR_CHECK(err_code);
    }

    //se non ci sono dati nella seriale e l'invio e' attivo
    if(p_event ->evt_type == APP_UART_TX_EMPTY && tx_enable){
      err_code = app_uart_put(value_R[counter]);
      APP_ERROR_CHECK(err_code);
      counter++;
      if(counter > 1){
        counter = 0;
        tx_enable = 1;
       }
    }
    if(p_event ->evt_type == APP_UART_DATA_READY){
      ...
    }
}

With the debugger i've seen that err_code is 0 after uart_put. Sometimes happen to go in the part of the FIFO_ERROR and stuff but not usually.

Thanks for the help

[awneil]

Have you looked at the UART example in the SDK ?

examples\peripheral\uart\

http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sdk5.v15.2.0/uart_example.html?cp=4_0_0_4_5_48

[Allen96]

Hi,

Thanks for the answer, i tried right now.

The code is not working.  It end at "NRF_BREAKPOINT_CND" and seems that the error is given from the "uarte_irq_handler" function.

I've tried it on 3 different board

Thanks for the support

[Einar Thorsrud]

NRF_BREAKPOINT_COND is probably due to an error check being hit (or a hard fault). You should define DEBUG for your project (just select the Debug build configuration from the dropdown if you are using SES) and enable logging. Then you will probably see from the log what went wrong.

For your reference, the implementation for the error handler is in app_error_wak.c (and the hardfault implementation is in hardfault_implementation.c).

[awneil]

Einar Thorsrud said:

app_error_wak.c

* app_error_weak.c