The latest development version of this page may be more current than this released 2.7.5 version.

CONFIG_BT_BUF_CMD_TX_SIZE¶

Maximum support HCI Command buffer length

Type: int

Help¶

Maximum data size for each HCI Command buffer. This value does not
include the HCI Command header.
This value is used by both the Host and the Controller for buffer
sizes that include HCI commands. It should be set according to the
expected HCI commands that can be sent from the configuration.
If the subset of possible HCI commands is unknown, this should be set
to the maximum of 255.

Direct dependencies¶

BT_HCI && BT

(Includes any dependencies from ifs and menus.)

Defaults¶

255 if BT_EXT_ADV || BT_BREDR
83 if !BT_EXT_ADV && !BT_BREDR && BT_CTLR_DF && BT_CTLR_DF_CONN_CTE_REQ && !SOC_COMPATIBLE_NRF
65

Kconfig definition¶

At subsys/bluetooth/common/Kconfig:165

Included via Kconfig:8 → Kconfig.zephyr:44 → subsys/Kconfig:9 → subsys/bluetooth/Kconfig:173

Menu path: (Top) → Sub Systems and OS Services → Bluetooth

config BT_BUF_CMD_TX_SIZE
    int "Maximum support HCI Command buffer length"
    range 65 255
    default 255 if BT_EXT_ADV || BT_BREDR
    default 83 if !BT_EXT_ADV && !BT_BREDR && BT_CTLR_DF && BT_CTLR_DF_CONN_CTE_REQ && !SOC_COMPATIBLE_NRF
    default 65
    depends on BT_HCI && BT
    help
      Maximum data size for each HCI Command buffer. This value does not
      include the HCI Command header.
      This value is used by both the Host and the Controller for buffer
      sizes that include HCI commands. It should be set according to the
      expected HCI commands that can be sent from the configuration.
      If the subset of possible HCI commands is unknown, this should be set
      to the maximum of 255.

(The ‘depends on’ condition includes propagated dependencies from ifs and menus.)