The

Link Layer Settings

parameters for the Link Layer.


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The maximum link layer transmits a payload size to be used in the design. The actual size of the link-layer transmit packet is decided based on the peer device’s link-layer receive packet size during Data Length Update Procedure and will be informed through the

CY_BLE_EVT_GAP_DATA_LENGTH_CHANGE

event. The valid range is 27 - 251 bytes.

The maximum link layer receives a payload size to be used in the design. The actual size of the link-layer receive packet is decided based on the peer device’s link-layer transmit packet size during Data Length Update Procedure and will be informed through

CY_BLE_EVT_GAP_DATA_LENGTH_CHANGE

event. The valid range is 27 - 251 bytes.

Setting

Link Layer Max TX Payload Size

or

Link Layer Max RX Payload Size

to the value greater than 27 enables the Low Energy Data Length Extension feature.


Filter accept list size​

The maximum number of devices that can be added to the

Filter accept list

. The valid range is 1 - 16. Default: 16.

Enables LL Privacy 1.2 feature of Bluetooth® 4.2 and enables generation of

CY_BLE_EVT_GAP_ENHANCE_CONN_COMPLETE

and

CY_BLE_EVT_GAPC_DIRECT_ADV_REPORT

events.

Note:

TheCY_BLE_EVT_GAP_DEVICE_CONNECTEDevent is not generated when this feature is enabled.


Resolving list size​

The maximum number of peer devices whose addresses should be resolved by this device. This parameter is applicable when the Enable Link Layer Privacy feature is enabled. The valid range is 1 - 16. Default:16.

Enable LE 2 Mbps​

Enables the LE 2 Mbps feature of Bluetooth® 5.0.

The LE 2 Mbps feature enables a new Physical (PHY) modulation scheme that allows increasing data throughput between the two devices which support this feature. Refer to Bluetooth® Core Specification v5.0 for more details about this feature.

Use the

Cy_BLE_SetDefaultPhy()

API after the

CY_BLE_EVT_STACK_ON

event to set the preferred default PHY for all connections, or the

Cy_BLE_SetPhy()

API to set PHY for the current connection.

The

CY_BLE_EVT_PHY_UPDATE_COMPLETE

event will indicate when the controller changes the transmitter PHY or receiver PHY in use.


Enable TX Power Calibration Retention​

When enabled, the Bluetooth® Low Energy radio TX power calibration is performed only once after programming and the calibration values are retained in the Sflash location. This retained value is reloaded to radio power calibration registers during consecutive device reboots. This reduces the Bluetooth® LE stack boot-up time significantly.

Note:

In Bluetooth® LE Dual-core mode, ensure to call theCy_SysDisableCM4()function before enabling the Bluetooth® LE controller [that is, before callingCy_BLE_Enable()on the controller core].


Note:

The calibration values are retained in user’s row 0 (afterBLE_DEVICE_ADDRESS) of the Sflash location.