Connection#

sl_bt_connection_role_t#

sl_bt_connection_role_t

Types of device roles in a Bluetooth connection.

sl_bt_connection_state_t#

sl_bt_connection_state_t

Connection states.

sl_bt_connection_security_t#

sl_bt_connection_security_t

Indicate the Bluetooth Security Mode.

sl_bt_connection_power_reporting_mode_t#

sl_bt_connection_power_reporting_mode_t

These values define transmit power reporting modes in LE power control.

sl_bt_connection_tx_power_flag_t#

sl_bt_connection_tx_power_flag_t

This enum defines the flag values for a reported transmit power level.

sl_bt_connection_set_default_parameters#

sl_status_t sl_bt_connection_set_default_parameters (uint16_t min_interval, uint16_t max_interval, uint16_t latency, uint16_t timeout, uint16_t min_ce_length, uint16_t max_ce_length)

Set default Bluetooth connection parameters. The values are valid for all subsequent connections initiated by this device.

min_ce_length and max_ce_length specify the preference of the connection event length so that the Link Layer can prioritize tasks accordingly in simultaneous connections, or scanning and so on. A connection event starts at an anchor point of a connection interval and lasts until the lesser of max_ce_length and the actual connection interval. Packets that do not fit into the connection event will be sent in the next connection interval.

To change parameters of an already established connection, use the command sl_bt_connection_set_parameters.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

sl_bt_connection_set_default_preferred_phy#

sl_status_t sl_bt_connection_set_default_preferred_phy (uint8_t preferred_phy, uint8_t accepted_phy)

Set default preferred and accepted PHYs. PHY settings will be used for all subsequent connections. Non-preferred PHY can also be set if the remote device does not accept any of the preferred PHYs.

The parameter accepted_phy is used to specify PHYs that the stack can accept in a remotely-initiated PHY update request. A PHY update will not happen if none of the accepted PHYs are present in the request.

NOTE: 2M and Coded PHYs are not supported by all devices.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

sl_bt_connection_set_default_data_length#

sl_status_t sl_bt_connection_set_default_data_length (uint16_t tx_data_len)

Set the default preferred maximum TX payload length to be used for new connections.

When a connection is open, the maximum TX payload length is 27. Either device could initiate a data length update procedure and event sl_bt_evt_connection_data_length is generated when the data length has been changed on the connection.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

sl_bt_connection_set_default_acceptable_subrate#

sl_status_t sl_bt_connection_set_default_acceptable_subrate (uint16_t min_subrate, uint16_t max_subrate, uint16_t max_latency, uint16_t continuation_number, uint16_t max_timeout)

Set the default acceptable parameters for subrating requests made by the peripheral on future ACL connections where this device is the central. The application must include the Connection Subrating feature (bluetooth_feature_connection_subrating) in order to use this command.

When a connection is established, central will store these values to determine if future subrate requests from the peripheral are acceptable. Peripheral may store it's own set of parameters independently but they will not be used in that role. Running this command has no effect on connections that are already active, instead to change the stored acceptable values, use the command sl_bt_connection_request_subrate on the central device.

Subrating is not automatically enabled on new a connection. Use the command sl_bt_connection_request_subrate to set the subrate parameters and enable subrating of a specific connection.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

sl_bt_connection_open#

sl_status_t sl_bt_connection_open (bd_addr address, uint8_t address_type, uint8_t initiating_phy, uint8_t * connection)

Connect to an advertising device with the specified initiating PHY on which connectable advertisements on primary advertising channels are received. The Bluetooth stack will enter a state where it continuously scans for the connectable advertising packets from the remote device, which matches the Bluetooth address given as a parameter. Scan parameters set in sl_bt_scanner_set_parameters are used in this operation. Upon receiving the advertising packet, the module will send a connection request packet to the target device to initiate a Bluetooth connection. To cancel an ongoing connection process, use sl_bt_connection_close command with the handle received in response from this command.

A connection is opened in no-security mode. If the GATT client needs to read or write the attributes on GATT server requiring encryption or authentication, it must first encrypt the connection using an appropriate authentication method.

If a connection can't be established, for example, the remote device has gone out of range, has entered into deep sleep, or is not advertising, the stack will try to connect forever. In this case, the application will not get an event related to the connection request. To recover from this situation, the application can implement a timeout and call sl_bt_connection_close to cancel the connection request.

This command fails with the connection limit exceeded error if the number of connections attempted exceeds the configured MAX_CONNECTIONS value.

This command fails with the invalid parameter error if the initiating PHY value is invalid or the device does not support PHY.

Subsequent calls of this command have to wait for the ongoing command to complete. A received event sl_bt_evt_connection_opened indicates that the connection opened successfully and a received event sl_bt_evt_connection_closed indicates that connection failures have occurred.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

Events

• sl_bt_evt_connection_opened - This event is triggered after the connection is opened and indicates whether the devices are already bonded and the role of the device in this connection.

• sl_bt_evt_connection_parameters - This event indicates the connection parameters and security mode of the connection.

sl_bt_connection_open_with_accept_list#

sl_status_t sl_bt_connection_open_with_accept_list (uint8_t initiating_phy, uint8_t * connection)

Connect to any device in the Filter Accept List, which enables the Auto Connection Establishment procedure on the local controller. The behavior of this command is the same as sl_bt_connection_open. The only difference is that sl_bt_connection_open opens a connection to a given peer device address.

See sl_bt_connection_open for more details.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

Events

• sl_bt_evt_connection_opened - This event is triggered after the connection is opened and indicates whether the devices are already bonded and the role of the device in this connection.

• sl_bt_evt_connection_parameters - This event indicates the connection parameters and security mode of the connection.

sl_bt_connection_set_parameters#

sl_status_t sl_bt_connection_set_parameters (uint8_t connection, uint16_t min_interval, uint16_t max_interval, uint16_t latency, uint16_t timeout, uint16_t min_ce_length, uint16_t max_ce_length)

Request a change in the connection parameters of a Bluetooth connection.

• On the central device the HCI LE Connection Update command is used to update the parameters.

• On the peripheral device an L2CAP connection parameter update request is sent to the peer device to update the parameters.

min_ce_length and max_ce_length specify the preference of the connection event length so that the Link Layer can prioritize tasks accordingly in simultaneous connections, or scanning and so on. A connection event starts at an anchor point of a connection interval and lasts until the lesser of max_ce_length and the actual connection interval. Packets that do not fit into the connection event will be sent in the next connection interval.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

Events

• sl_bt_evt_connection_parameters - Triggered after new connection parameters are applied on the connection.

• sl_bt_evt_connection_set_parameters_failed - Triggered when the peer device rejected an L2CAP connection parameter update request.

sl_bt_connection_set_preferred_phy#

sl_status_t sl_bt_connection_set_preferred_phy (uint8_t connection, uint8_t preferred_phy, uint8_t accepted_phy)

Set preferred and accepted PHYs for a given connection. Event sl_bt_evt_connection_phy_status is received when PHY update procedure is completed. Non-preferred PHY can also be set if remote device does not accept any of the preferred PHYs.

The parameter accepted_phy is used for specifying the PHYs that the stack can accept in a remote initiated PHY update request. A PHY update will not occur if none of the accepted PHYs presents in the request.

NOTE: 2M and Coded PHYs are not supported by all devices.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

Events

• sl_bt_evt_connection_phy_status

sl_bt_connection_disable_slave_latency#

sl_status_t sl_bt_connection_disable_slave_latency (uint8_t connection, uint8_t disable)

Temporarily enable or disable peripheral latency. Used only when Bluetooth device is acting as a peripheral. When peripheral latency is disabled, the peripheral latency connection parameter is not set to 0 but the device will wake up on every connection interval to receive and send packets.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

sl_bt_connection_get_median_rssi#

sl_status_t sl_bt_connection_get_median_rssi (uint8_t connection, int8_t * rssi)

Get the RSSI value measured on a connection.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

sl_bt_connection_read_channel_map#

sl_status_t sl_bt_connection_read_channel_map (uint8_t connection, size_t max_channel_map_size, size_t * channel_map_len, uint8_t * channel_map)

Read channel map for a specified connection.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

sl_bt_connection_set_power_reporting#

sl_status_t sl_bt_connection_set_power_reporting (uint8_t connection, uint8_t mode)

Enable or disable the transmit power reporting for the local device on a connection. When transmit power reporting is enabled, event sl_bt_evt_connection_tx_power is generated when transmit power on the local device changes.

The command is a built-in feature in the stack and is supported regardless of whether the LE Power Control feature is used. By default, power reporting for local device is enabled.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

Events

• sl_bt_evt_connection_tx_power

sl_bt_connection_set_remote_power_reporting#

sl_status_t sl_bt_connection_set_remote_power_reporting (uint8_t connection, uint8_t mode)

Enable or disable reporting the transmit power change on the remote device. The application must include the LE Power Control feature (bluetooth_feature_power_control) in order to use this command.

When the remote transmit power reporting is enabled, event sl_bt_evt_connection_remote_tx_power is generated when transmit power on the remote device changes.

By default, power reporting for the remote device is disabled.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

Events

• sl_bt_evt_connection_remote_tx_power

sl_bt_connection_get_tx_power#

sl_status_t sl_bt_connection_get_tx_power (uint8_t connection, uint8_t phy, int8_t * current_level, int8_t * max_level)

Get the transmit power of the local device on the given connection and PHY. The application must include the LE Power Control feature (bluetooth_feature_power_control) in order to use this command.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

sl_bt_connection_get_remote_tx_power#

sl_status_t sl_bt_connection_get_remote_tx_power (uint8_t connection, uint8_t phy)

Get the transmit power of the remote device on the given connection and PHY. The application must include the LE Power Control feature (bluetooth_feature_power_control) in order to use this command. Transmit power levels are returned in event sl_bt_evt_connection_get_remote_tx_power_completed after the operation completed.

Returns

• SL_STATUS_OK if the command is accepted. Error code otherwise.

Events

• sl_bt_evt_connection_get_remote_tx_power_completed

sl_bt_connection_set_tx_power#

sl_status_t sl_bt_connection_set_tx_power (uint8_t connection, int16_t tx_power, int16_t * tx_power_out)

Set the transmit power of a connection. The application must include component bluetooth_feature_user_power_control in order to use this command for controlling the transmit power of the connection at application level. This command is unavailable if the standard Bluetooth feature LE power control (component bluetooth_feature_power_control) is used by the application.

The actual selected power level is returned from this command. The value may be different than the requested one because of Bluetooth feature restrictions or radio characteristics.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

sl_bt_connection_read_remote_used_features#

sl_status_t sl_bt_connection_read_remote_used_features (uint8_t connection)

Read link layer features supported by the remote device.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

Events

• sl_bt_evt_connection_remote_used_features

sl_bt_connection_get_security_status#

sl_status_t sl_bt_connection_get_security_status (uint8_t connection, uint8_t * security_mode, uint8_t * key_size, uint8_t * bonding_handle)

Get the security status of the connection.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

sl_bt_connection_set_data_length#

sl_status_t sl_bt_connection_set_data_length (uint8_t connection, uint16_t tx_data_len, uint16_t tx_time_us)

Request to update the maximum TX payload length and maximum packet TX time of a Bluetooth connection.

Event sl_bt_evt_connection_data_length is generated when the data length has been changed on the connection.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

Events

• sl_bt_evt_connection_data_length

sl_bt_connection_read_statistics#

sl_status_t sl_bt_connection_read_statistics (uint8_t connection, uint8_t reset)

Read the statistic values collected on the specified connection. The application must include component bluetooth_feature_connection_statistics in order to use this command. If the component is not included in the application this command returns the error SL_STATUS_NOT_AVAILABLE. If this command is called before the connection has opened, the command returns the error SL_STATUS_NOT_READY.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

Events

• sl_bt_evt_connection_statistics - Triggered to deliver the statistic values of the connection at the time the command was issued.

sl_bt_connection_get_scheduling_details#

sl_status_t sl_bt_connection_get_scheduling_details (uint8_t connection, uint32_t * access_address, uint8_t * role, uint32_t * crc_init, uint16_t * interval, uint16_t * supervision_timeout, uint8_t * central_clock_accuracy, uint8_t * central_phy, uint8_t * peripheral_phy, uint8_t * channel_selection_algorithm, uint8_t * hop, sl_bt_connection_channel_map_t * channel_map, uint8_t * channel, uint16_t * event_counter, uint32_t * start_time_us)

Get parameters and next connection event scheduling details of a connection. Returned values from this command provide the necessary information for following the packet transmissions of the connection on an external device. Note that the stack cannot ensure a determined timing latency from the time when issuing this command to the time when another device starts to follow the connection, and the stack cannot guarantee that a scheduled connection event will always happen.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

sl_bt_connection_get_remote_address#

sl_status_t sl_bt_connection_get_remote_address (uint8_t connection, bd_addr * address, uint8_t * address_type)

Get the Bluetooth address of the remote device on the given connection.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

sl_bt_connection_request_subrate#

sl_status_t sl_bt_connection_request_subrate (uint8_t connection, uint16_t min_subrate, uint16_t max_subrate, uint16_t max_latency, uint16_t continuation_number, uint16_t timeout)

Request a change to the subrating factor and other parameters applied to an existing connection. The application must include the Connection Subrating feature (bluetooth_feature_connection_subrating) in order to use this command.

If the local device is in the central role on this connection, this command overrides the default acceptable subrating parameters set by sl_bt_connection_set_default_acceptable_subrate and uses the specified subrate parameters for this connection. If the local device is in the peripheral role on this connection, this command requests a change to the parameters but they may not be accepted by the peer central device.

If the connection parameters are changed (see command sl_bt_connection_set_parameters and event sl_bt_evt_connection_parameters) after subrate parameters were successfully applied, the latency and timeout from sl_bt_evt_connection_parameters take effect and the subrate_factor is reset to 1 and the continuation_number to 0 for the connection. Use this command sl_bt_connection_request_subrate again after the connection parameter change to re-enable subrating.

This command returns SL_STATUS_BT_CTRL_UNSUPPORTED_REMOTE_FEATURE when the device is in central role on the connection and the peripheral does not support the subrate feature.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

Events

• sl_bt_evt_connection_subrate_changed - Triggered when the request to change the subrate parameters has been successfully completed.

• sl_bt_evt_connection_request_subrate_failed - Triggered when the request to change the subrate parameters has failed.

sl_bt_connection_get_state#

sl_status_t sl_bt_connection_get_state (uint8_t connection, uint8_t * state)

Get the state of the given connection.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

sl_bt_connection_close#

sl_status_t sl_bt_connection_close (uint8_t connection)

Close a Bluetooth connection gracefully by performing the ACL Termination procedure or cancel an ongoing connection establishment process. The parameter is a connection handle which is reported in sl_bt_evt_connection_opened event or sl_bt_connection_open command response.

Disconnecting a connection is an asynchronous operation. The disconnection is completed when a sl_bt_evt_connection_closed event for the given connection handle is received. To open a new connection to the same remote device, wait for the sl_bt_evt_connection_closed event and then initiate the connection.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

Events

• sl_bt_evt_connection_closed

sl_bt_connection_forcefully_close#

sl_status_t sl_bt_connection_forcefully_close (uint8_t connection)

Forcefully close a Bluetooth connection without performing the ACL Termination procedure. The parameter is a connection handle which is reported in sl_bt_evt_connection_opened event or sl_bt_connection_open command response.

Closing a connection using this command could result in the observation of connection loss or supervision timeout on the remote device. Only use this command for special cases, for example, when disconnecting a connection with sl_bt_connection_close did not complete in expected time period.

Returns

• SL_STATUS_OK if successful. Error code otherwise.

Events

• sl_bt_evt_connection_closed

sl_bt_cmd_connection_set_default_parameters_id#

#define sl_bt_cmd_connection_set_default_parameters_id

0x00060020

sl_bt_cmd_connection_set_default_preferred_phy_id#

#define sl_bt_cmd_connection_set_default_preferred_phy_id

0x01060020

sl_bt_cmd_connection_set_default_data_length_id#

#define sl_bt_cmd_connection_set_default_data_length_id

0x10060020

sl_bt_cmd_connection_set_default_acceptable_subrate_id#

#define sl_bt_cmd_connection_set_default_acceptable_subrate_id

0x19060020

sl_bt_cmd_connection_open_id#

#define sl_bt_cmd_connection_open_id

0x04060020

sl_bt_cmd_connection_open_with_accept_list_id#

#define sl_bt_cmd_connection_open_with_accept_list_id

0x16060020

sl_bt_cmd_connection_set_parameters_id#

#define sl_bt_cmd_connection_set_parameters_id

0x06060020

sl_bt_cmd_connection_set_preferred_phy_id#

#define sl_bt_cmd_connection_set_preferred_phy_id

0x08060020

sl_bt_cmd_connection_disable_slave_latency_id#

#define sl_bt_cmd_connection_disable_slave_latency_id

0x03060020

sl_bt_cmd_connection_get_median_rssi_id#

#define sl_bt_cmd_connection_get_median_rssi_id

0x15060020

sl_bt_cmd_connection_read_channel_map_id#

#define sl_bt_cmd_connection_read_channel_map_id

0x07060020

sl_bt_cmd_connection_set_power_reporting_id#

#define sl_bt_cmd_connection_set_power_reporting_id

0x09060020

sl_bt_cmd_connection_set_remote_power_reporting_id#

#define sl_bt_cmd_connection_set_remote_power_reporting_id

0x0a060020

sl_bt_cmd_connection_get_tx_power_id#

#define sl_bt_cmd_connection_get_tx_power_id

0x0b060020

sl_bt_cmd_connection_get_remote_tx_power_id#

#define sl_bt_cmd_connection_get_remote_tx_power_id

0x0c060020

sl_bt_cmd_connection_set_tx_power_id#

#define sl_bt_cmd_connection_set_tx_power_id

0x12060020

sl_bt_cmd_connection_read_remote_used_features_id#

#define sl_bt_cmd_connection_read_remote_used_features_id

0x0d060020

sl_bt_cmd_connection_get_security_status_id#

#define sl_bt_cmd_connection_get_security_status_id

0x0e060020

sl_bt_cmd_connection_set_data_length_id#

#define sl_bt_cmd_connection_set_data_length_id

0x11060020

sl_bt_cmd_connection_read_statistics_id#

#define sl_bt_cmd_connection_read_statistics_id

0x13060020

sl_bt_cmd_connection_get_scheduling_details_id#

#define sl_bt_cmd_connection_get_scheduling_details_id

0x14060020

sl_bt_cmd_connection_get_remote_address_id#

#define sl_bt_cmd_connection_get_remote_address_id

0x17060020

sl_bt_cmd_connection_request_subrate_id#

#define sl_bt_cmd_connection_request_subrate_id

0x1a060020

sl_bt_cmd_connection_get_state_id#

#define sl_bt_cmd_connection_get_state_id

0x18060020

sl_bt_cmd_connection_close_id#

#define sl_bt_cmd_connection_close_id

0x05060020

sl_bt_cmd_connection_forcefully_close_id#

#define sl_bt_cmd_connection_forcefully_close_id

0x0f060020

sl_bt_rsp_connection_set_default_parameters_id#

#define sl_bt_rsp_connection_set_default_parameters_id

0x00060020

sl_bt_rsp_connection_set_default_preferred_phy_id#

#define sl_bt_rsp_connection_set_default_preferred_phy_id

0x01060020

sl_bt_rsp_connection_set_default_data_length_id#

#define sl_bt_rsp_connection_set_default_data_length_id

0x10060020

sl_bt_rsp_connection_set_default_acceptable_subrate_id#

#define sl_bt_rsp_connection_set_default_acceptable_subrate_id

0x19060020

sl_bt_rsp_connection_open_id#

#define sl_bt_rsp_connection_open_id

0x04060020

sl_bt_rsp_connection_open_with_accept_list_id#

#define sl_bt_rsp_connection_open_with_accept_list_id

0x16060020

sl_bt_rsp_connection_set_parameters_id#

#define sl_bt_rsp_connection_set_parameters_id

0x06060020

sl_bt_rsp_connection_set_preferred_phy_id#

#define sl_bt_rsp_connection_set_preferred_phy_id

0x08060020

sl_bt_rsp_connection_disable_slave_latency_id#

#define sl_bt_rsp_connection_disable_slave_latency_id

0x03060020

sl_bt_rsp_connection_get_median_rssi_id#

#define sl_bt_rsp_connection_get_median_rssi_id

0x15060020

sl_bt_rsp_connection_read_channel_map_id#

#define sl_bt_rsp_connection_read_channel_map_id

0x07060020

sl_bt_rsp_connection_set_power_reporting_id#

#define sl_bt_rsp_connection_set_power_reporting_id

0x09060020

sl_bt_rsp_connection_set_remote_power_reporting_id#

#define sl_bt_rsp_connection_set_remote_power_reporting_id

0x0a060020

sl_bt_rsp_connection_get_tx_power_id#

#define sl_bt_rsp_connection_get_tx_power_id

0x0b060020

sl_bt_rsp_connection_get_remote_tx_power_id#

#define sl_bt_rsp_connection_get_remote_tx_power_id

0x0c060020

sl_bt_rsp_connection_set_tx_power_id#

#define sl_bt_rsp_connection_set_tx_power_id

0x12060020

sl_bt_rsp_connection_read_remote_used_features_id#

#define sl_bt_rsp_connection_read_remote_used_features_id

0x0d060020

sl_bt_rsp_connection_get_security_status_id#

#define sl_bt_rsp_connection_get_security_status_id

0x0e060020

sl_bt_rsp_connection_set_data_length_id#

#define sl_bt_rsp_connection_set_data_length_id

0x11060020

sl_bt_rsp_connection_read_statistics_id#

#define sl_bt_rsp_connection_read_statistics_id

0x13060020

sl_bt_rsp_connection_get_scheduling_details_id#

#define sl_bt_rsp_connection_get_scheduling_details_id

0x14060020

sl_bt_rsp_connection_get_remote_address_id#

#define sl_bt_rsp_connection_get_remote_address_id

0x17060020

sl_bt_rsp_connection_request_subrate_id#

#define sl_bt_rsp_connection_request_subrate_id

0x1a060020

sl_bt_rsp_connection_get_state_id#

#define sl_bt_rsp_connection_get_state_id

0x18060020

sl_bt_rsp_connection_close_id#

#define sl_bt_rsp_connection_close_id

0x05060020

sl_bt_rsp_connection_forcefully_close_id#

#define sl_bt_rsp_connection_forcefully_close_id

0x0f060020