Controller && VHCI

Application Examples

API Reference

Header File

  • components/bt/include/esp32c3/include/esp_bt.h

  • This header file can be included with:

    #include "esp_bt.h"

  • This header file is a part of the API provided by the bt component. To declare that your component depends on bt, add the following to your CMakeLists.txt:

    REQUIRES bt

    or

    PRIV_REQUIRES bt

Functions

esp_err_t esp_bt_controller_init(esp_bt_controller_config_t *cfg)

Initialize the Bluetooth Controller to allocate tasks and other resources.

Note

This function should be called only once, before any other Bluetooth functions.

Parameters

cfg -- [in] Initial Bluetooth Controller configuration

Returns

  • ESP_OK: Success

  • ESP_ERR_INVALID_STATE: Invalid Bluetooth Controller state

  • ESP_ERR_NOT_SUPPORTED: Invalid Bluetooth Controller mode

  • ESP_ERR_INVALID_ARG: Invalid arguments

  • ESP_ERR_NO_MEM: Out of memory

  • ESP_FAIL: Failure due to other reasons

esp_err_t esp_bt_controller_deinit(void)

De-initialize Bluetooth Controller to free resources and delete tasks.

Note

  1. You should make sure that the Controller is in idle state before de-initializing it.

  2. This function should be called only once, after any other Bluetooth functions.

Returns

  • ESP_OK: Success

  • ESP_ERR_INVALID_ARG: Invalid arguments

  • ESP_ERR_INVALID_STATE: Invalid Bluetooth Controller state

  • ESP_ERR_NO_MEM: Out of memory

esp_err_t esp_bt_controller_enable(esp_bt_mode_t mode)

Enable Bluetooth Controller.

For API compatibility, retain this argument. This mode must match the mode specified in the cfg of esp_bt_controller_init().

Note

  1. Bluetooth Controller cannot be enabled in ESP_BT_CONTROLLER_STATUS_IDLE status. It has to be initialized first.

  2. Due to a known issue, you cannot call esp_bt_controller_enable() for the second time to change the Controller mode dynamically. To change the Controller mode, call esp_bt_controller_disable() and then call esp_bt_controller_enable() with the new mode.

Parameters

mode -- [in] The Bluetooth Controller mode to enable

Returns

  • ESP_OK: Success

  • ESP_ERR_INVALID_STATE: Invalid Bluetooth Controller state

  • ESP_ERR_INVALID_ARG: Invalid arguments

esp_err_t esp_bt_controller_disable(void)

Disable Bluetooth Controller.

Returns

  • ESP_OK: Success

  • ESP_ERR_INVALID_STATE: Invalid Bluetooth Controller state

esp_bt_controller_status_t esp_bt_controller_get_status(void)

Get Bluetooth Controller status.

Returns

  • ESP_BT_CONTROLLER_STATUS_IDLE: The Controller is not initialized or has been de-initialized.

  • ESP_BT_CONTROLLER_STATUS_INITED: The Controller has been initialized, but not enabled or has been disabled.

  • ESP_BT_CONTROLLER_STATUS_ENABLED: The Controller has been initialized and enabled.

esp_err_t esp_bt_controller_mem_release(esp_bt_mode_t mode)

Release the Controller memory as per the mode.

This function releases the BSS, data and other sections of the Controller to heap. The total size is about 70 KB.

If you never intend to use Bluetooth in a current boot-up cycle, calling esp_bt_controller_mem_release(ESP_BT_MODE_BLE) could release the BSS and data consumed by BLE Controller to heap.

Note

  1. This function is optional and should be called only if you want to free up memory for other components.

  2. This function should only be called when the Controller is in ESP_BT_CONTROLLER_STATUS_IDLE status.

  3. Once Bluetooth Controller memory is released, the process cannot be reversed. This means you cannot use the Bluetooth Controller mode that you have released using this function.

  4. If your firmware will upgrade the Bluetooth Controller mode later (such as from disabled to enabled), then do not call this function.

Parameters

mode -- [in] The Bluetooth Controller mode

Returns

  • ESP_OK: Success

  • ESP_ERR_INVALID_STATE: Invalid Bluetooth Controller state

  • ESP_ERR_NOT_FOUND: Requested resource not found

esp_err_t esp_bt_mem_release(esp_bt_mode_t mode)

Release the Controller memory, BSS and data section of the BLE Host stack as per the mode.

This function first releases Controller memory by internally calling esp_bt_controller_mem_release(), then releases Host memory.

If you never intend to use Bluetooth in a current boot-up cycle, calling esp_bt_mem_release(ESP_BT_MODE_BLE) could release the BSS and data consumed by BLE stack to heap.

For example, if you only use Bluetooth for setting the Wi-Fi configuration, and do not use Bluetooth in the rest of the product operation, after receiving the Wi-Fi configuration, you can disable/de-init Bluetooth and release its memory. Below is the sequence of APIs to be called for such scenarios: 

  esp_bluedroid_disable();
  esp_bluedroid_deinit();
  esp_bt_controller_disable();
  esp_bt_controller_deinit();
  esp_bt_mem_release(ESP_BT_MODE_BLE);

Note

  1. This function is optional and should be called only if you want to free up memory for other components.

  2. This function should only be called when the Controller is in ESP_BT_CONTROLLER_STATUS_IDLE status.

  3. Once Bluetooth Controller memory is released, the process cannot be reversed. This means you cannot use the Bluetooth Controller mode that you have released using this function.

  4. If your firmware will upgrade the Bluetooth Controller mode later (such as from disabled to enabled), then do not call this function.

Parameters

mode -- [in] The Bluetooth Controller mode

Returns

  • ESP_OK: Success

  • ESP_ERR_INVALID_STATE: Invalid Bluetooth Controller state

  • ESP_ERR_NOT_FOUND: Requested resource not found

esp_err_t esp_bt_sleep_enable(void)

Enable Bluetooth modem sleep.

There are currently two options for Bluetooth modem sleep: ORIG mode and EVED mode. The latter is intended for BLE only. The modem sleep mode could be configured in menuconfig.

In ORIG mode, if there is no event to process, the Bluetooth Controller will periodically switch off some components and pause operation, then wake up according to the scheduled interval and resume work. It can also wakeup earlier upon external request using function esp_bt_controller_wakeup_request().

Note

This function shall not be invoked before esp_bt_controller_enable().

Returns

  • ESP_OK: Success

  • ESP_ERR_INVALID_STATE: Invalid Bluetooth Controller state

  • ESP_ERR_NOT_SUPPORTED: Operation or feature not supported

esp_err_t esp_bt_sleep_disable(void)

Disable Bluetooth modem sleep.

Note

  1. Bluetooth Controller will not be allowed to enter modem sleep after calling this function.

  2. In ORIG modem sleep mode, calling this function may not immediately wake up the Controller if it is currently dormant. In this case, esp_bt_controller_wakeup_request() can be used to shorten the wake-up time.

  3. This function shall not be invoked before esp_bt_controller_enable().

Returns

  • ESP_OK: Success

  • ESP_ERR_INVALID_STATE: Invalid Bluetooth Controller state

  • ESP_ERR_NOT_SUPPORTED: Operation or feature not supported

esp_bt_sleep_clock_t esp_bt_get_lpclk_src(void)

Get the Bluetooth sleep clock source.

Note

This function shall not be invoked before esp_bt_controller_init().

Returns

clock source used in Bluetooth low power mode

bool esp_bt_controller_is_sleeping(void)

Check if the Bluetooth Controller is currently in sleep mode when modem sleep is enabled.

Note

  1. This function shall not be invoked before esp_bt_controller_enable().

  2. This function is supposed to be used ORIG mode of modem sleep.

Returns

  • True if the Controller is in modem sleep state; false otherwise.

void esp_bt_controller_wakeup_request(void)

Request the Controller to wakeup from sleeping state during sleep mode.

Profiling shows that it takes several milliseconds to wakeup from modem sleep after this request.

Generally it takes longer if 32kHz XTAL is used than the main XTAL, due to the lower frequency of the former as the bluetooth low power clock source.

Note

  1. This function shall not be invoked before esp_bt_controller_enable().

  2. This function is supposed to be used ORIG mode of modem sleep.

  3. After this request, the Bluetooth Controller can re-enter sleep as long as modem sleep remains enabled.

esp_err_t esp_ble_tx_power_set(esp_ble_power_type_t power_type, esp_power_level_t power_level)

Set BLE TX power for the specified power type.

It is recommended to use esp_ble_tx_power_set_enhanced to set TX power for individual advertising and connection handle.

Note

Connection TX power should only be set after the connection is established.

Parameters

  • power_type -- [in] The type of TX power. It could be Advertising, Connection, or Default.

  • power_level -- [in] Power level (index) corresponding to the absolute value (dBm)

Returns

  • ESP_OK: Success

  • ESP_ERR_NOT_SUPPORTED: Invalid TX power type

  • ESP_FAIL: Failure due to other reasons

esp_power_level_t esp_ble_tx_power_get(esp_ble_power_type_t power_type)

Get BLE TX power of the specified power type.

It is recommended to use esp_ble_tx_power_get_enhanced to get TX power of individual advertising and connection handle.

Note

  1. Connection TX power should only be retrieved after the connection is established.

  2. If an invalid power type is provided, this API returns ESP_PWR_LVL_INVALID.

Parameters

power_type -- [in] The type of TX power. It could be Advertising/Connection/Default and etc.

Returns

  • Power level

esp_err_t esp_ble_tx_power_set_enhanced(esp_ble_enhanced_power_type_t power_type, uint16_t handle, esp_power_level_t power_level)

Set BLE TX power for the specified Advertising or Connection handle.

For the TX power type: ESP_BLE_ENHANCED_PWR_TYPE_DEFAULT, ESP_BLE_ENHANCED_PWR_TYPE_SCAN, ESP_BLE_ENHANCED_PWR_TYPE_INIT, this API will ignore the input handle number, and set 0 internally.

For the TX power type: ESP_BLE_ENHANCED_PWR_TYPE_ADV and ESP_BLE_ENHANCED_PWR_TYPE_CONN， this API will set the TX power for the target handle.

Note

  1. Connection TX power should only be set after connection created.

Parameters

  • power_type -- [in] The type of TX power

  • handle -- [in] The handle of Advertising or Connection

  • power_level -- [in] Power level (index) corresponding to absolute value (dBm)

Returns

  • ESP_OK: Success

  • ESP_ERR_NOT_SUPPORTED: Invalid TX power type

  • ESP_FAIL: Failure due to other reasons

esp_power_level_t esp_ble_tx_power_get_enhanced(esp_ble_enhanced_power_type_t power_type, uint16_t handle)

Get BLE TX power of the specified Advertising or Connection handle.

For the TX power type: ESP_BLE_ENHANCED_PWR_TYPE_DEFAULT, ESP_BLE_ENHANCED_PWR_TYPE_SCAN, ESP_BLE_ENHANCED_PWR_TYPE_INIT, this API will ignore the input handle number.

For the TX power type: ESP_BLE_ENHANCED_PWR_TYPE_ADV and ESP_BLE_ENHANCED_PWR_TYPE_CONN， this API will return the TX power of the target handle.

Note

  1. Connection Tx power should only be get after connection created.

  2. If an invalid power type is provided, this API returns ESP_PWR_LVL_INVALID.

Parameters

  • power_type -- [in] The type of TX power

  • handle -- [in] The handle of Advertising or Connection and the value 0 for other enhanced power types

Returns

Power level

int esp_bt_h4tl_eif_io_event_notify(int event)

Notify Bluetooth Controller task to process the event upon TX or RX done.

Note

  1. This function shall not be invoked before esp_bt_controller_enable().

  2. This function can be called in both ISR and non-ISR context.

  3. This function ignored the passed event value currently

bool esp_vhci_host_check_send_available(void)

Check whether the Controller is ready to receive the HCI data.

If the return value is True, the Host can send the HCI data to the Controller.

Note

This function should be called before each esp_vhci_host_send_packet().

Returns

True if the Controller is ready to receive the HCI data; false otherwise.

void esp_vhci_host_send_packet(uint8_t *data, uint16_t len)

Send the HCI data to the Controller.

Note

  1. This function shall not be called within a critical section or when the scheduler is suspended.

  2. This function should be called only if esp_vhci_host_check_send_available returns True.

Parameters

  • data -- [in] Pointer to the HCI data

  • len -- [in] The HCI data length

esp_err_t esp_vhci_host_register_callback(const esp_vhci_host_callback_t *callback)

Register the VHCI callback functions defined in esp_vhci_host_callback structure.

Parameters

callback -- [in] esp_vhci_host_callback type variable

Returns

  • ESP_OK: Success

  • ESP_FAIL: Failure

Structures

struct esp_bt_hci_tl_t

Controller HCI transport layer function structure.

Note

This structure must be registered when HCI transport layer is UART

Public Members

uint32_t _magic

Magic number

uint32_t _version

Version number of the defined structure

uint32_t _reserved

Reserved for future use

int (*_open)(void)

HCI transport layer open function

void (*_close)(void)

HCI transport layer close function

void (*_finish_transfers)(void)

HCI transport layer finish transfers function

void (*_recv)(uint8_t *buf, uint32_t len, esp_bt_hci_tl_callback_t callback, void *arg)

HCI transport layer receive function

void (*_send)(uint8_t *buf, uint32_t len, esp_bt_hci_tl_callback_t callback, void *arg)

HCI transport layer send function

bool (*_flow_off)(void)

HCI transport layer flow off function

void (*_flow_on)(void)

HCI transport layer flow on function

struct esp_bt_controller_config_t

Bluetooth Controller config options.

Note

  1. For parameters configurable through menuconfig, it is recommended to adjust them via the menuconfig interface. Please refer to menuconfig for details on the range and default values.

  2. It is not recommended to modify the values for parameters which are not configurable through menuconfig.

Public Members

uint32_t magic

Magic number

uint32_t version

version number of the defined structure

uint16_t controller_task_stack_size

Bluetooth Controller task stack size in bytes

uint8_t controller_task_prio

Bluetooth Controller task priority

uint8_t controller_task_run_cpu

CPU number that Bluetooth Controller task runs on. Configurable in menuconfig.

  • 0 - CPU 0 (default)

  • 1 - CPU 1

uint8_t bluetooth_mode

BLE mode

uint8_t ble_max_act

The maximum number of BLE instance. Configurable in menuconfig.

  • Range: 1 - 10

  • Default: 6

uint8_t sleep_mode

Modem sleep mode. Configurable in menuconfig.

  • 0 - Disable (default)

  • 1 - Enable

uint8_t sleep_clock

Modem sleep clock source. Configurable in menuconfig.

uint8_t ble_st_acl_tx_buf_nb

Static ACL TX buffer numbers. Configurable in menuconfig.

  • Range: 0 - 12

  • Default: 0

uint8_t ble_hw_cca_check

Deprecated

uint16_t ble_adv_dup_filt_max

The maximum number of extended duplicate scan filter. Configurable in menuconfig.

  • Range: 1 - 500

  • Default: 30

bool coex_param_en

Deprecated

uint8_t ce_len_type

Connection event length determination method. Configurable in menuconfig.

  • 0 - Original (default)

  • 1 - use CE_LEN parameter from HCI commands

  • 2 - Espressif vendor defined method

bool coex_use_hooks

Deprecated

uint8_t hci_tl_type

HCI transport layer type. Configurable in menuconfig.

  • 0 - URAT

  • 1 - Virtual HCI (default)

esp_bt_hci_tl_t *hci_tl_funcs

HCI transport functions used. It must be set when hci_tl_type is UART.

uint8_t txant_dft

Default TX antenna. Configurable in menuconfig.

  • 0 - Antenna 0 (default)

  • 1 - Antenna 1

uint8_t rxant_dft

Default RX antenna. Configurable in menuconfig.

  • 0 - Antenna 0 (default)

  • 1 - Antenna 1

uint8_t txpwr_dft

Default TX power. Please refer to esp_power_level_t for supported power level. Configurable in menuconfig.

  • Default : ESP_PWR_LVL_P9 +9 dBm.

uint32_t cfg_mask

Configuration mask to set specific options

uint8_t scan_duplicate_mode

Scan duplicate filtering mode. Configurable in menuconfig.

  • 0 - Normal scan duplicate filtering mode (default)

  • 1 - Special scan duplicate filtering mode for BLE Mesh

uint8_t scan_duplicate_type

Scan duplicate filtering type. If scan_duplicate_mode is set to 1, this parameter will be ignored. Configurable in menuconfig.

  • 0 - Filter scan duplicates by device address only (default)

  • 1 - Filter scan duplicates by advertising data only, even if they originate from different devices.

  • 2 - Filter scan duplicated by device address and advertising data.

uint16_t normal_adv_size

Maximum number of devices in scan duplicate filtering list. Configurable in menuconfig.

  • Range: 10 - 1000

  • Default: 100

uint16_t mesh_adv_size

Maximum number of Mesh advertising packets in scan duplicate filtering list. Configurable in menuconfig.

  • Range: 10 - 1000

  • Default: 100

uint8_t coex_phy_coded_tx_rx_time_limit

Enable / disable the maximum TX/RX time limit for Coded-PHY connections in coexistence with Wi-Fi scenarios. Configurable in menuconfig.

  • 0 - Disable (default)

  • 1 - Enable

uint32_t hw_target_code

Hardware target. Internal use only. Please do not modify this value.

uint8_t slave_ce_len_min

Slave minimum connection event length: 5 slots. Please do not modify this value.

uint8_t hw_recorrect_en

Enable / disable uncoded phy / coded phy hardware re-correction. Configurable in menuconfig.

uint8_t cca_thresh

Absolute value of hardware-triggered CCA threshold. The CCA threshold is always negative. If the channel assessment result exceeds the CCA threshold (e.g. -75 dBm), indicating the channel is busy, the hardware will not transmit packets on that channel. Configurable in menuconfig.

  • Range: 20 dBm - 100 dBm

  • Default: 75 dBm

uint16_t scan_backoff_upperlimitmax

Enable / disable active scan backoff. Configurable in menuconfig.

  • 0 - Disable (default)

  • 1 - Enable

uint16_t dup_list_refresh_period

Scan duplicate filtering list refresh period in seconds. Configurable in menuconfig

  • Range: 0 - 100 seconds

  • Default: 0 second

bool ble_50_feat_supp

True if BLE 5.0 features are enabled; false otherwise. This option depends on whether the Host enable the 5.0 features.

uint8_t ble_cca_mode

BLE CCA mode. Configurable in menuconfig

  • 0 - Disable (default)

  • 1 - Hardware-triggered CCA

  • 2 - Software-based CCA

uint8_t ble_data_lenth_zero_aux

Enable / disable auxiliary packets when the extended ADV data length is zero. Configurable in menuconfig.

  • 0 - Disable (default)

  • 1 - Enable

uint8_t ble_chan_ass_en

Enable / disable BLE channel assessment. Configurable in menuconfig.

  • 0 - Disable

  • 1 - Enable (default)

uint8_t ble_ping_en

Enable / disable BLE ping procedure. Configurable in menuconfig.

  • 0 - Disable

  • 1 - Enable (default)

uint8_t ble_llcp_disc_flag

Flag indicating whether the Controller disconnects after Instant Passed (0x28) error occurs. Configurable in menuconfig.

  • The Controller does not disconnect after Instant Passed (0x28) by default.

bool run_in_flash

True if the Controller code is in flash (flash model); false otherwise (default). Configurable in menuconfig.

bool dtm_en

In the flash mode, True if the DTM feature is enabled; false otherwise (default). Configurable in menuconfig.

bool enc_en

In the flash mode, True if the encryption feature is enabled (default); false otherwise. Configurable in menuconfig.

bool qa_test

In the flash mode, True if the QA test feature is enabled; false otherwise (default). Configurable in menuconfig.

bool master_en

In the flash mode, True if the master feature is enabled (default); false otherwise. Configurable in menuconfig.

bool scan_en

In the flash mode, True if the scan feature is enabled (default); false otherwise. Configurable in menuconfig.

bool ble_aa_check

True if adds a verification step for the Access Address within the CONNECT_IND PDU; false otherwise. Configurable in menuconfig

struct esp_vhci_host_callback

Virtual HCI (VHCI) callback functions to notify the Host on the next operation.

Public Members

void (*notify_host_send_available)(void)

callback used to notify that the Host can send the HCI data to Controller

int (*notify_host_recv)(uint8_t *data, uint16_t len)

callback used to notify that the Controller has the HCI data to send to the Host

Macros

ESP_BT_CTRL_CONFIG_MAGIC_VAL

Internal use only.

Note

Please do not modify this value

ESP_BT_CTRL_CONFIG_VERSION

Internal use only.

Note

Please do not modify this value

ESP_BT_HCI_TL_MAGIC_VALUE

Internal use only.

Note

Please do not modify this value

ESP_BT_HCI_TL_VERSION

Internal use only.

Note

Please do not modify this value

ESP_BT_HCI_TL_STATUS_OK

HCI_TL TX/RX operation status OK

BT_CONTROLLER_INIT_CONFIG_DEFAULT()

Type Definitions

typedef void (*esp_bt_hci_tl_callback_t)(void *arg, uint8_t status)

Callback function for HCI Transport Layer send/receive operations.

typedef struct esp_vhci_host_callback esp_vhci_host_callback_t

Virtual HCI (VHCI) callback functions to notify the Host on the next operation.

Enumerations

enum esp_bt_mode_t

Bluetooth Controller mode.

Values:

enumerator ESP_BT_MODE_IDLE

Bluetooth is not operating.

enumerator ESP_BT_MODE_BLE

Bluetooth is operating in BLE mode.

enumerator ESP_BT_MODE_CLASSIC_BT

Unsupported mode

enumerator ESP_BT_MODE_BTDM

Unsupported mode

enum esp_bt_ctrl_hci_tl_t

BLE Controller HCI transport layer type.

Values:

enumerator ESP_BT_CTRL_HCI_TL_UART

HCI UART h4 transport layer

enumerator ESP_BT_CTRL_HCI_TL_VHCI

Virtual HCI interface

enum esp_ble_ce_len_t

BLE connection event length computation type.

Values:

enumerator ESP_BLE_CE_LEN_TYPE_ORIG

original

enumerator ESP_BLE_CE_LEN_TYPE_CE

use CE_LEN parameter from HCI commands

enumerator ESP_BLE_CE_LEN_TYPE_SD

Espressif vendor defined

enum esp_bt_sleep_mode_t

Bluetooth modem sleep mode.

Values:

enumerator ESP_BT_SLEEP_MODE_NONE

Disable modem sleep

enumerator ESP_BT_SLEEP_MODE_1

Enable modem sleep

enum esp_bt_sleep_clock_t

Bluetooth modem sleep clock source.

Note

If the modem sleep mode is enabled, ESP_BT_SLEEP_CLOCK_MAIN_XTAL is the default option and ESP_BT_SLEEP_CLOCK_NONE will become an invalid option.

Values:

enumerator ESP_BT_SLEEP_CLOCK_NONE

Sleep clock not configured

enumerator ESP_BT_SLEEP_CLOCK_MAIN_XTAL

SoC main crystal

enumerator ESP_BT_SLEEP_CLOCK_EXT_32K_XTAL

External 32.768kHz crystal

enumerator ESP_BT_SLEEP_CLOCK_RTC_SLOW

Internal 136kHz RC oscillator

enumerator ESP_BT_SLEEP_CLOCK_FPGA_32K

Hardwired 32KHz clock temporarily used for FPGA

enum [anonymous]

Bluetooth antenna index.

Values:

enumerator ESP_BT_ANT_IDX_0

Antenna NO 0

enumerator ESP_BT_ANT_IDX_1

Antenna NO 1

enum [anonymous]

Enable / disable the maximum TX/RX time limit for Coded-PHY connections in coexistence with Wi-Fi scenarios.

Values:

enumerator ESP_BT_COEX_PHY_CODED_TX_RX_TIME_LIMIT_FORCE_DISABLE

Disable the limit

enumerator ESP_BT_COEX_PHY_CODED_TX_RX_TIME_LIMIT_FORCE_ENABLE

Enable the limit

enum esp_bt_controller_status_t

Bluetooth Controller status.

Values:

enumerator ESP_BT_CONTROLLER_STATUS_IDLE

The Controller is not initialized or has been de-initialized.

enumerator ESP_BT_CONTROLLER_STATUS_INITED

The Controller has been initialized, but not enabled or has been disabled.

enumerator ESP_BT_CONTROLLER_STATUS_ENABLED

The Controller has been initialized and enabled.

enumerator ESP_BT_CONTROLLER_STATUS_NUM

Number of Controller statuses

enum esp_ble_power_type_t

BLE TX power type.

This TX power type is used for the API esp_ble_tx_power_set() and esp_ble_tx_power_get().

Note

  1. The connection TX power can only be set after the connection is established. After disconnecting, the corresponding TX power will not be affected.

  2. ESP_BLE_PWR_TYPE_DEFAULT can be used to set the TX power for power types that have not been set before. It will not affect the TX power values which have been set for the ADV/SCAN/CONN0-8 power types.

  3. If none of power type is set, the system will use ESP_PWR_LVL_P3 as default for all power types.

Values:

enumerator ESP_BLE_PWR_TYPE_CONN_HDL0

TX power for Connection state handle 0

enumerator ESP_BLE_PWR_TYPE_CONN_HDL1

TX power for Connection state handle 1

enumerator ESP_BLE_PWR_TYPE_CONN_HDL2

TX power for Connection state handle 2

enumerator ESP_BLE_PWR_TYPE_CONN_HDL3

TX power for Connection state handle 3

enumerator ESP_BLE_PWR_TYPE_CONN_HDL4

TX power for Connection state handle 4

enumerator ESP_BLE_PWR_TYPE_CONN_HDL5

TX power for Connection state handle 5

enumerator ESP_BLE_PWR_TYPE_CONN_HDL6

TX power for Connection state handle 6

enumerator ESP_BLE_PWR_TYPE_CONN_HDL7

TX power for Connection state handle 7

enumerator ESP_BLE_PWR_TYPE_CONN_HDL8

TX power for Connection state handle 8

enumerator ESP_BLE_PWR_TYPE_ADV

TX power for Advertising state

enumerator ESP_BLE_PWR_TYPE_SCAN

TX power for Scanning state

enumerator ESP_BLE_PWR_TYPE_DEFAULT

TX power for states that have not been set before

enumerator ESP_BLE_PWR_TYPE_NUM

Reserved

enum esp_ble_enhanced_power_type_t

The enhanced type of which TX power, could set Advertising/Connection/Default and etc.

This TX power type is used for the API esp_ble_tx_power_set_enhanced() and esp_ble_tx_power_get_enhanced().

Note

  1. The connection TX power can only be set after the connection is established. After disconnecting, the corresponding TX power will not be affected.

  2. ESP_BLE_ENHANCED_PWR_TYPE_DEFAULT can be used to set the TX power for power types that have not been set before. It will not affect the TX power values which have been set for the ADV/SCAN/INIT/CONN power types.

  3. If none of power type is set, the system will use ESP_PWR_LVL_P3 as default for all power types.

Values:

enumerator ESP_BLE_ENHANCED_PWR_TYPE_DEFAULT

TX power for states that have not been set before

enumerator ESP_BLE_ENHANCED_PWR_TYPE_ADV

TX power for Advertising state

enumerator ESP_BLE_ENHANCED_PWR_TYPE_SCAN

TX power for Scanning state

enumerator ESP_BLE_ENHANCED_PWR_TYPE_INIT

TX power for Initiating state

enumerator ESP_BLE_ENHANCED_PWR_TYPE_CONN

TX power for Connection state

enumerator ESP_BLE_ENHANCED_PWR_TYPE_MAX

Reserved

enum esp_power_level_t

Bluetooth TX power level (index). Each index corresponds to a specific power value in dBm.

Values:

enumerator ESP_PWR_LVL_N24

Corresponding to -24 dBm

enumerator ESP_PWR_LVL_N21

Corresponding to -21 dBm

enumerator ESP_PWR_LVL_N18

Corresponding to -18 dBm

enumerator ESP_PWR_LVL_N15

Corresponding to -15 dBm

enumerator ESP_PWR_LVL_N12

Corresponding to -12 dBm

enumerator ESP_PWR_LVL_N9

Corresponding to -9 dBm

enumerator ESP_PWR_LVL_N6

Corresponding to -6 dBm

enumerator ESP_PWR_LVL_N3

Corresponding to -3 dBm

enumerator ESP_PWR_LVL_N0

Corresponding to 0 dBm

enumerator ESP_PWR_LVL_P3

Corresponding to +3 dBm

enumerator ESP_PWR_LVL_P6

Corresponding to +6 dBm

enumerator ESP_PWR_LVL_P9

Corresponding to +9 dBm

enumerator ESP_PWR_LVL_P12

Corresponding to +12 dBm

enumerator ESP_PWR_LVL_P15

Corresponding to +15 dBm

enumerator ESP_PWR_LVL_P18

Corresponding to +18 dBm

enumerator ESP_PWR_LVL_P20

Corresponding to +20 dBm

enumerator ESP_PWR_LVL_P21

Deprecated

enumerator ESP_PWR_LVL_INVALID

Indicates an invalid value

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