Hi, i am having some trouble getting my nRF52 DK (S132) to read a value provided by the nRF51 dongle(S130). First of all, i am very new to this whole Bluetooth thing so i've done all the tutorials, tried some things and had fun - so far. But now im stuck: I used the mulitlink_peripheral example on the dongle, set up the characteristics and values which i can read from the smartphone MCP. So all UUIDs and values und stuff are known and appear in MCP. This is where i figured out, i have to make changes to costumize the service i copied from multilink peripheral
static void services_init(void) {
uint32_t err_code;
ble_uuid_t uuid;
ble_gatts_char_md_t char_md;
ble_gatts_attr_t attr;
ble_gatts_attr_md_t attr_md;
ble_gatts_attr_md_t cccd_md;
ble_gatts_attr_md_t char_ud_md;
uint16_t svc_test;
ble_uuid128_t base_uuid = MULTILINK_PERIPHERAL_BASE_UUID;
err_code = sd_ble_uuid_vs_add(&base_uuid, &m_base_uuid_type);
APP_ERROR_CHECK(err_code);
uuid.type = m_base_uuid_type;
uuid.uuid = MULTILINK_PERIPHERAL_SERVICE_UUID;
err_code = sd_ble_gatts_service_add(BLE_GATTS_SRVC_TYPE_PRIMARY, &uuid, &svc_test); /**< Service will be added */
APP_ERROR_CHECK(err_code);
//////////
static uint8_t multilink_peripheral_data = 101; /**< Actual Value of Characteristic, range 0-255, changing to uint16_t seems to stop functionality */
static uint8_t multilink_peripheral_ud[] = "Keycode Hex 1"; /**< Descriptor of Characteristic Value */
uuid.uuid = MULTILINK_PERIPHERAL_CHAR1_UUID; /**< Set Characteristic UUID from #define */
memset(&attr, 0, sizeof(ble_gatts_attr_t)); /**< write 0 to ble_gatts_attr_t attr to make sure attr is not on random values */
attr.p_uuid = &uuid;
attr.p_attr_md = &attr_md;
attr.max_len = 1;
attr.p_value = &multilink_peripheral_data;
attr.init_len = sizeof(multilink_peripheral_data);
memset(&attr_md, 0, sizeof(ble_gatts_attr_md_t));
BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.read_perm);
BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&attr_md.write_perm);
attr_md.vloc = BLE_GATTS_VLOC_STACK;
attr_md.vlen = 0;
memset(&cccd_md, 0, sizeof(ble_gatts_attr_md_t));
BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.read_perm);
BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&cccd_md.write_perm);
cccd_md.vloc = BLE_GATTS_VLOC_STACK;
memset(&char_md, 0, sizeof(ble_gatts_char_md_t));
char_md.p_cccd_md = &cccd_md;
char_md.char_props.notify = 1; /**< comment / uncomment to set permissions */
char_md.char_props.indicate = 1;
char_md.char_props.read = 1;
char_md.char_props.write = 1;
char_md.char_ext_props.wr_aux = 1; /**< needs to stay 1 */
char_md.p_user_desc_md = &char_ud_md;
char_md.p_char_user_desc = multilink_peripheral_ud;
char_md.char_user_desc_size = (uint8_t)strlen((char *)multilink_peripheral_ud);
char_md.char_user_desc_max_size = (uint8_t)strlen((char *)multilink_peripheral_ud);
memset(&char_ud_md, 0, sizeof(ble_gatts_attr_md_t));
char_ud_md.vloc = BLE_GATTS_VLOC_STACK;
char_ud_md.vlen = 1;
BLE_GAP_CONN_SEC_MODE_SET_OPEN(&char_ud_md.read_perm);
BLE_GAP_CONN_SEC_MODE_SET_OPEN(&char_ud_md.write_perm);
err_code = sd_ble_gatts_characteristic_add(BLE_GATT_HANDLE_INVALID,
&char_md,
&attr,
&m_char_handles);
APP_ERROR_CHECK(err_code);
next thing i want to do is to read the value stored in
static uint8_t multilink_peripheral_data = 101;
from my nrf52 DK which then lights up a LED when compared the 101 to another value stored on the nrf52 DK. In the infocenter I found this flowchart: GATTC Read Characteristic Value by UUID
but somehow i cannot figure out how to make this function work. e.g. i don't know where the conn_handle comes from. Infocenter just tells me: this is the connection handle, which i already figured out from the name...
do i have to call some other functions first, or set up some structs to make this work? thanks for the help so far. I'm trying to be precise, but as i am new to this, it's a bit difficult. And thanks for recommending the app_hrs and battery service, but since i set up my peripheral device and it appears in MCP as I wish, i'd rather like to stick with this code, than getting to know a new one which wasn't very familiar looking.
best regards selle
