Hello, I am writing code for Nrf52832 using Segger Embedded studio SDK 17.1. I want to store the data received from BLU NUS into a variable for further processing but am not sure how to do this.

[mjconnor57]

HI I am having trouble converting the NUS example into something that simply stores the BLE nus response to the peripheral into a variable rather than printing it to the UART. Can you please show me an example of how this can be done?

Here is my current code in main.c, it does get triggered when i write from the NRF COnnect app on my Android but as far as I can tell there is no data passed to the buffer.

static void nus_data_handler(ble_nus_evt_t * p_evt)
{
    uint16_t length;
    static char data_array[6];
    static char temp_data_array[40];
    static int array;
    static uint8_t index = 0;

    static char ap_ssid[40];
    static char ap_pwd[40];

    if (p_evt->type == BLE_NUS_EVT_RX_DATA)
    {

      for (uint32_t i = 0; i < p_evt->params.rx_data.length; i++)
      {
        temp_data_array[i] = p_evt->params.rx_data.p_data[i];
      }
        substring(data_array, temp_data_array, 0, 6);
        uint32_t err_code;

        NRF_LOG_INFO("Received data from BLE NUS. Writing data on UART.");
        NRF_LOG_HEXDUMP_DEBUG(p_evt->params.rx_data.p_data, p_evt->params.rx_data.length);
        if (temp_data_array == "AP_SSI")
        {
          array = 1;
        }
        else if (temp_data_array == "AP_PWD")
        {
          array = 2;
        }

        switch(array)
        {

          case 1:
            index = 7; //precursor is actually AP_SSID, 7 characters we need to omit

            while(p_evt->params.rx_data.p_data[index] != 0x3F)
            {
              
              app_uart_put(p_evt->params.rx_data.p_data[index]);
              index++;
            }
            length = index;
            memcpy(ssid, p_evt->params.rx_data.p_data, length);
            app_uart_put(0x0A);

            break;

          case 2:

            index = 6;

            while(p_evt->params.rx_data.p_data[index] != 0x3F)
            {
              app_uart_put(p_evt->params.rx_data.p_data[index]);
              index++;
            }
            length = index;
            memcpy(password, p_evt->params.rx_data.p_data, length);
            app_uart_put(0x0A);

            break;

          default:
            break;
         }
   }
 
}

[Hieu]

Hi mjconnor57,

Are these lines pseudocode or your actual code? If they are actual code, I think they are the issue.

        if (temp_data_array == "AP_SSI")
        {
          array = 1;
        }
        else if (temp_data_array == "AP_PWD")
        {
          array = 2;
        }

Please refer to: https://stackoverflow.com/questions/8004237/how-do-i-properly-compare-strings-in-c

By the way, are you sure you need all those variable static?
Also, if you plan to have significant processing, you probably want to put the data into a FIFO to defer processing to the main loop. 

Hieu

[Hieu]

Hi mjconnor57, I noticed you replied with some follow up questions, but later deleted it and closed this thread. I just want to quickly check, is everything alright now?