Hi everyone for my application I must use the Bluegiga dongle like central (PC side) and nRF51822 for peripheral (hardware side). So I implemented cable replacement app and I created a new service starting from ble_nus.c (see ble_app_uart example) and the suggestions that I found here devzone.nordicsemi.com/.../. This service use only one custom characteristic for matching with the dongle, in indicate mode. I put the snippet code below:
static uint32_t tx_char_add(ble_nus_t * p_nus, const ble_nus_init_t * p_nus_init)
{
ble_gatts_char_md_t char_md;
ble_gatts_attr_md_t cccd_md;
ble_gatts_attr_t attr_char_value;
ble_uuid_t ble_tx_uuid;
ble_gatts_attr_md_t attr_md;
uint32_t err_code;
memset(&cccd_md, 0, sizeof(cccd_md));
BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.read_perm);
BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.write_perm);
cccd_md.vloc = BLE_GATTS_VLOC_STACK;
memset(&char_md, 0, sizeof(char_md));
char_md.char_props.write = 1;
char_md.char_props.indicate = 1;
char_md.p_char_user_desc = NULL;
char_md.p_char_pf = NULL;
char_md.p_user_desc_md = NULL;
char_md.p_cccd_md = &cccd_md;
char_md.p_sccd_md = NULL;
ble_uuid128_t nus_tx_base_uuid = NUS_TX_BASE_UUID;
err_code = sd_ble_uuid_vs_add(&nus_tx_base_uuid, &ble_tx_uuid.type);
if (err_code != NRF_SUCCESS)
{
return err_code;
}
ble_tx_uuid.uuid = BLE_UUID_NUS_TX_CHARACTERISTIC;
memset(&attr_md, 0, sizeof(attr_md));
BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.read_perm);
BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.write_perm);
attr_md.vloc = BLE_GATTS_VLOC_STACK;
attr_md.rd_auth = 0;
attr_md.wr_auth = 0;
attr_md.vlen = 1;
memset(&attr_char_value, 0, sizeof(attr_char_value));
attr_char_value.p_uuid = &ble_tx_uuid;
attr_char_value.p_attr_md = &attr_md;
attr_char_value.init_len = 1;
attr_char_value.init_offs = 0;
attr_char_value.max_len = BLE_NUS_MAX_TX_CHAR_LEN;
return sd_ble_gatts_characteristic_add(p_nus->service_handle,
&char_md,
&attr_char_value,
&p_nus->tx_handles);
}
...
void ble_nus_on_ble_evt(ble_nus_t * p_nus, ble_evt_t * p_ble_evt)
{
if ((p_nus == NULL) || (p_ble_evt == NULL))
{
return;
}
switch (p_ble_evt->header.evt_id)
{
case BLE_GAP_EVT_CONNECTED:
on_connect(p_nus, p_ble_evt);
break;
case BLE_GAP_EVT_DISCONNECTED:
on_disconnect(p_nus, p_ble_evt);
break;
case BLE_GATTS_EVT_WRITE:
on_write(p_nus, p_ble_evt);
break;
case BLE_GATTS_EVT_HVC:
on_hvc(p_nus, p_ble_evt);
break;
default:
// No implementation needed.
break;
}
}
...
uint32_t ble_nus_send_string(ble_nus_t * p_nus, uint8_t * string, uint16_t length)
{
ble_gatts_hvx_params_t hvx_params;
if (p_nus == NULL)
{
return NRF_ERROR_NULL;
}
if ((p_nus->conn_handle == BLE_CONN_HANDLE_INVALID))
{
return NRF_ERROR_INVALID_STATE;
}
if (length > BLE_NUS_MAX_DATA_LEN)
{
return NRF_ERROR_INVALID_PARAM;
}
memset(&hvx_params, 0, sizeof(hvx_params));
hvx_params.handle = p_nus->rx_handles.value_handle;
hvx_params.p_data = string;
hvx_params.p_len = &length;
hvx_params.type = BLE_GATT_HVX_INDICATION;
return sd_ble_gatts_hvx(p_nus->conn_handle, &hvx_params);
}
It works fine, when I transmit some data from PC I receive the data in Uart line; but if I transmit data from hardware there is some issues. If I transmit data <20 byte, PC receive it but not always and if I transmit data >20 byte the NRF51822 disconnect. I think that my modify is not enough... I have some problem with indicate service, I think... Some suggestion? If anyone are interesting about this application I'm available to discuss it.
Thanks a lot. Paolo A.
