Create BLE characteristic with notifications active on queued write service

[naf18]

I'm developing an application to communicate with a smartphone. I have the need of writing characteristics with the size bigger than the negotiated MTU, so I'm exploring Queued write example. So far, I'm able to write to the characteristic, however, I need to have two characteristics, one used to write and another to read with the possibility of push notifications.

To do that I tried to change the source code to add a characteristic with "read" and "notify" permissions, as you can see below:

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ble_add_char_params_t add_char_params;

memset(&add_char_params, 0, sizeof(add_char_params));

add_char_params.uuid = BLE_UUID_QWRS_LONG_CHARACTERISTIC;

add_char_params.max_len = BLE_QWRS_MAX_LONG_CHAR_LEN;

add_char_params.init_len = 0;

add_char_params.char_props.write = true;

add_char_params.write_access = SEC_OPEN;

add_char_params.is_defered_write = true;

err_code = characteristic_add(p_qwrs->service_handle,

&add_char_params,

&p_qwrs->long_charact_handles);

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

    ble_add_char_params_t add_char_params;

    memset(&add_char_params, 0, sizeof(add_char_params));
    add_char_params.uuid               = BLE_UUID_QWRS_LONG_CHARACTERISTIC;
    add_char_params.max_len            = BLE_QWRS_MAX_LONG_CHAR_LEN;
    add_char_params.init_len           = 0;
    add_char_params.char_props.write   = true;
    add_char_params.write_access       = SEC_OPEN;
    add_char_params.is_defered_write   = true;

    err_code = characteristic_add(p_qwrs->service_handle,
                                  &add_char_params,
                                  &p_qwrs->long_charact_handles);

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ble_add_char_params_t add_char_params;

memset(&add_char_params, 0, sizeof(add_char_params));

add_char_params.uuid = BLE_UUID_QWRS_LONG_CHARACTERISTIC;

add_char_params.max_len = BLE_QWRS_MAX_LONG_CHAR_LEN;

add_char_params.init_len = 0;

add_char_params.char_props.read = true;

add_char_params.char_props.notify = true;

add_char_params.read_access = SEC_OPEN;

err_code = characteristic_add(p_qwrs->service_handle,

&add_char_params,

&p_qwrs->long_charact_handles);

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

    ble_add_char_params_t add_char_params;

    memset(&add_char_params, 0, sizeof(add_char_params));
    add_char_params.uuid               = BLE_UUID_QWRS_LONG_CHARACTERISTIC;
    add_char_params.max_len            = BLE_QWRS_MAX_LONG_CHAR_LEN;
    add_char_params.init_len           = 0;
    add_char_params.char_props.read    = true;
    add_char_params.char_props.notify  = true;
    add_char_params.read_access       = SEC_OPEN;

    err_code = characteristic_add(p_qwrs->service_handle,
                                  &add_char_params,
                                  &p_qwrs->long_charact_handles);

After that change I received an error code "NRF_INVALID_PARAM" and the characteristic is not added. I also tried to add the read permission only and that works fine.

Can somebody help me to understand how can I add notify permissions?

Note: I am using nordic SDK v13.0.0.