How to pair nearby via RSSI

Question

hello, 
 if i want to connect to a peripheral device with strongest RSSI. I need to get the RSSI before connecting. 
 and i know i can get the RSSI from event of BLE_GAP_EVT_ADV_REPORT. 
 But there is a lot of peripheral devices around central device. how can i distinguish which peripheral device these RSSI come from?

yu1998 · Answer

typedef struct
{
 ble_gap_adv_report_type_t type; /**< Advertising report type. See @ref ble_gap_adv_report_type_t. */
 ble_gap_addr_t peer_addr; /**< Bluetooth address of the peer device. If the peer_addr is resolved:
 @ref ble_gap_addr_t::addr_id_peer is set to 1 and the address is the
 peer's identity address. */
 ble_gap_addr_t direct_addr; /**< Contains the target address of the advertising event if
 @ref ble_gap_adv_report_type_t::directed is set to 1. If the
 SoftDevice was able to resolve the address,
 @ref ble_gap_addr_t::addr_id_peer is set to 1 and the direct_addr
 contains the local identity address. If the target address of the
 advertising event is @ref BLE_GAP_ADDR_TYPE_RANDOM_PRIVATE_RESOLVABLE,
 and the SoftDevice was unable to resolve it, the application may try
 to resolve this address to find out if the advertising event was
 directed to us. */
 uint8_t primary_phy; /**< Indicates the PHY on which the primary advertising packet was received.
 See @ref BLE_GAP_PHYS. */
 uint8_t secondary_phy; /**< Indicates the PHY on which the secondary advertising packet was received.
 See @ref BLE_GAP_PHYS. This field is set to @ref BLE_GAP_PHY_NOT_SET if no packets
 were received on a secondary advertising channel. */
 int8_t tx_power; /**< TX Power reported by the advertiser in the last packet header received.
 This field is set to @ref BLE_GAP_POWER_LEVEL_INVALID if the
 last received packet did not contain the Tx Power field.
 @note TX Power is only included in extended advertising packets. */
 int8_t rssi; /**< Received Signal Strength Indication in dBm of the last packet received.
 @note ERRATA-153 and ERRATA-225 require the rssi sample to be compensated based on a temperature measurement. */
 uint8_t ch_index; /**< Channel Index on which the last advertising packet is received (0-39). */
 uint8_t set_id; /**< Set ID of the received advertising data. Set ID is not present
 if set to @ref BLE_GAP_ADV_REPORT_SET_ID_NOT_AVAILABLE. */
 uint16_t data_id:12; /**< The advertising data ID of the received advertising data. Data ID
 is not present if @ref ble_gap_evt_adv_report_t::set_id is set to
 @ref BLE_GAP_ADV_REPORT_SET_ID_NOT_AVAILABLE. */
 ble_data_t data; /**< Received advertising or scan response data. If
 @ref ble_gap_adv_report_type_t::status is not set to
 @ref BLE_GAP_ADV_DATA_STATUS_INCOMPLETE_MORE_DATA, the data buffer provided
 in @ref sd_ble_gap_scan_start is now released. */
 ble_gap_aux_pointer_t aux_pointer; /**< The offset and PHY of the next advertising packet in this extended advertising
 event. @note This field is only set if @ref ble_gap_adv_report_type_t::status
 is set to @ref BLE_GAP_ADV_DATA_STATUS_INCOMPLETE_MORE_DATA. */
} ble_gap_evt_adv_report_t; 
 
 in ble. gap.h you cat get all information you need 
 each struct can distinguish with ble_data_t data; 
 or address itself 
 typedef struct
{
 bool is_not_empty; /**< Indicates that the structure is not empty. */
 deviceType cnt_type;
 uint8_t addr[BLE_GAP_ADDR_LEN]; /**< Device address. */
 
 char dev_name[DEVICE_NAME_MAX_SIZE]; /**< Device name. */

 
} scanned_device_t;

or you can just check the adreess with scanned_device_t in ble_m.h 
 or if you are lucky the device do have device name compare with Name

i wrote some app before i think both of this can accomplish your goal

How to pair nearby via RSSI

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