i want to do simple data transfer and why blueetooth serial terminal was not be able to detect the device?

[venkatesha kj]

how to do simple data transfer using bluetooth serail terminal?

[Karl Ylvisaker]

Hello,

You could use the BLE NUS peripheral and central examples to do such a transfer between your devices.
The examples will relay anything they receive over UART to their connected peer over BLE, and the peer will output the messages received over BLE out on its UART, and visa versa.
Test this according to the example documentation, and let me know if you encounter any issues or questions.

Best regards,
Karl

[venkatesha kj]

i go through the nsu code but which api was used to transfer the data?

[venkatesha kj]

-40dBm, -20dBm, -16dBm, -12dBm, -8dBm, -4dBm, 0dBm, +3dBm and +4dBm.
* In addition, on some chips following values are supported: +2dBm, +5dBm, +6dBm, +7dBm and +8dBm.

can i use any of the above transmission power levels for nrf52840 development kit?

[Karl Ylvisaker]

venkatesha kj said:

but it was not increased in my case?

It is not guaranteed - it depends on a lot of external factors in the environement.

venkatesha kj said:

can i use any of the above transmission power levels for nrf52840 development kit?

You can use the values specified as valid for the TXPOWER register in the documentation for the SoC you are working with, which I linked earlier.

Best regards,
Karl

[venkatesha kj]

how to check the rssi level of the central device in the pheripheral device?

[venkatesha kj]

i want to scan the central device and check the rssi level of the central device how do i do that?

[venkatesha kj]

app: RSSI: 206
<info> app: RSSI: 195
<info> app: RSSI: 180
<info> app: RSSI: 179
<info> app: RSSI: 164
<info> app: RSSI: 171
<info> app: RSSI: 173
<info> app: RSSI: 179
<info> app: RSSI: 174
<info> app: RSSI: 176
<info> app: RSSI: 170
<info> app: RSSI: 175
<info> app: RSSI: 177
<info> app: RSSI: 180
<info> app: RSSI: 176
<info> app: RSSI: 180
<info> app: RSSI: 180
<info> app: RSSI: 181
<info> app: RSSI: 181
<info> app: RSSI: 180
<info> app: RSSI: 182

i started measuring the rssi level when i am near to the device its showing high values but when i move away from the device its showing lower values. But in nrf connect it value is negitive and showing lower negitive values when i am near to the device. will the values returned from the rssi get function are correct?

[Karl Ylvisaker]

venkatesha kj said:

i want to scan the central device and check the rssi level of the central device how do i do that?

The peripheral does not do any scanning.
You can still use sd_ble_gap_rssi_get on the peripheral to retrieve the RSSI of the last connection event on the peripheral's side.

venkatesha kj said:

i started measuring the rssi level when i am near to the device its showing high values but when i move away from the device its showing lower values. But in nrf connect it value is negitive and showing lower negitive values when i am near to the device. will the values returned from the rssi get function are correct?

How did you produce these values? They do not seem like any RSSI values I have ever seen before. Could it be that you have formatted or type-casted them improperly?

Best regards,
Karl

[venkatesha kj]

i got the output properly i am suppose to use int8_t variable

[Karl Ylvisaker]

Please share the section of the code in which you did this, using the Insert -> Code option.

Best regards,
Karl

[venkatesha kj]

void bsp_event_handler(bsp_event_t event)
{
    uint32_t err_code;
   // uint8_t count = 48;
  // uint8_t data_array1 = count;
   // uint8_t len = sizeof(count);
    char count[] = "hi serobit";
    uint8_t len = strlen(count);
    switch (event)
    {
        case BSP_EVENT_SLEEP:
            sleep_mode_enter();
            break;

        case BSP_EVENT_DISCONNECT:
            err_code = sd_ble_gap_disconnect(m_conn_handle, BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
            if (err_code != NRF_ERROR_INVALID_STATE)
            {
                APP_ERROR_CHECK(err_code);
            }
            break;

        case BSP_EVENT_WHITELIST_OFF:
            if (m_conn_handle == BLE_CONN_HANDLE_INVALID)
            {
                err_code = ble_advertising_restart_without_whitelist(&m_advertising);
                if (err_code != NRF_ERROR_INVALID_STATE)
                {
                    APP_ERROR_CHECK(err_code);
                }
            }
            break;
         case BSP_EVENT_KEY_2:
            // Set_Count(count-48);
             err_code = ble_nus_data_send(&m_nus, count, &len, m_conn_handle);
           // err_code = ble_nus_data_send(&m_nus, &str, &len, m_conn_handle);


        default:
            break;
    }
}

i try to send the data when ever the button intterupt occured but not be able to see the data on nrf-connect app?

[Karl Ylvisaker]

Have you verified that your code ever enters into the BSP_EVENT_KEY_2 case?

Please check the error code returned by your call to ble_nus_data_send. If you do not check the returned error code you will never be alerted if the function call fails unexpectedly.
Please also make sure to have DEBUG defined in your preprocessor defines, like shown in the included image:


This will make your logger output a detailed error message whenever a non-NRF_SUCCESS error code is passed to an APP_ERROR_CHECK.

Best regards,
Karl