Controller && VHCI

Application Example

Check bluetooth/hci folder in ESP-IDF examples, which contains the following application:

This is a Bluetooth® Low Energy (Bluetooth LE) advertising demo with virtual HCI interface. Send Reset/ADV_PARAM/ADV_DATA/ADV_ENABLE HCI command for Bluetooth Low Energy advertising - bluetooth/hci/controller_vhci_ble_adv.

API Reference

Header File

components/bt/include/esp32c6/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_ble_tx_power_set(esp_ble_power_type_t power_type, esp_power_level_t power_level)

Set BLE TX power Connection Tx power should only be set after connection created.

Parameters

power_type -- : The type of which tx power, could set Advertising/Connection/Default and etc
power_level -- Power level(index) corresponding to absolute value(dbm)

Returns

ESP_OK - success, other - failed

esp_power_level_t esp_ble_tx_power_get(esp_ble_power_type_t power_type)

Get BLE TX power Connection Tx power should only be get after connection created.

Parameters: power_type -- : The type of which tx power, could set Advertising/Connection/Default and etc
Returns: >= 0 - Power level, < 0 - Invalid

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)

ENHANCED API for Setting BLE TX power Connection Tx power should only be set after connection created.

Parameters

power_type -- : The enhanced type of which tx power, could set Advertising/Connection/Default and etc.
handle -- : The handle of Advertising or Connection and the value 0 for other enhanced power types.
power_level -- Power level(index) corresponding to absolute value(dbm)

Returns

ESP_OK - success, other - failed

esp_power_level_t esp_ble_tx_power_get_enhanced(esp_ble_enhanced_power_type_t power_type, uint16_t handle)

ENHANCED API of Getting BLE TX power Connection Tx power should only be get after connection created.

Parameters

power_type -- : The enhanced type of which tx power, could set Advertising/Connection/Default and etc
handle -- : The handle of Advertising or Connection and the value 0 for other enhanced power types.

Returns

>= 0 - Power level, < 0 - Invalid

esp_err_t esp_bt_controller_init(esp_bt_controller_config_t *cfg)

Initialize BT controller to allocate task and other resource. This function should be called only once, before any other BT functions are called.

Parameters: cfg -- Initial configuration of BT controller.
Returns: ESP_OK - success, other - failed

esp_bt_controller_status_t esp_bt_controller_get_status(void)

Get BT controller is initialised/de-initialised/enabled/disabled.

Returns: status value

esp_err_t esp_bt_controller_deinit(void)

De-initialize BT controller to free resource and delete task. You should stop advertising and scanning, as well as disconnect all existing connections before de-initializing BT controller.

This function should be called only once, after any other BT functions are called. This function is not whole completed, esp_bt_controller_init cannot called after this function.

Returns: ESP_OK - success, other - failed

esp_err_t esp_bt_controller_enable(esp_bt_mode_t mode)

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

Parameters: mode -- : the mode(BLE/BT/BTDM) to enable. For compatible of API, retain this argument.
Returns: ESP_OK - success, other - failed

esp_err_t esp_bt_controller_disable(void)

Disable BT controller.

Returns: ESP_OK - success, other - failed

bool esp_vhci_host_check_send_available(void)

esp_vhci_host_check_send_available used for check actively if the host can send packet to controller or not.

Returns: true for ready to send, false means cannot send packet

void esp_vhci_host_send_packet(uint8_t *data, uint16_t len)

esp_vhci_host_send_packet host send packet to controller

Should not call this function from within a critical section or when the scheduler is suspended.

Parameters

data -- the packet point
len -- the packet length

esp_err_t esp_vhci_host_register_callback(const esp_vhci_host_callback_t *callback)

esp_vhci_host_register_callback register the vhci reference callback struct defined by vhci_host_callback structure.

Parameters: callback -- esp_vhci_host_callback type variable
Returns: ESP_OK - success, ESP_FAIL - failed

esp_err_t esp_bt_controller_mem_release(esp_bt_mode_t mode)

esp_bt_controller_mem_release 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 70k bytes.

esp_bt_controller_mem_release(mode) should be called only before esp_bt_controller_init() or after esp_bt_controller_deinit().

Note that once BT controller memory is released, the process cannot be reversed. It means you cannot use the bluetooth mode which you have released by this function.

If your firmware will later upgrade the Bluetooth controller mode (BLE -> BT Classic or disabled -> enabled) then do not call this function.

If the app calls esp_bt_controller_enable(ESP_BT_MODE_BLE) to use BLE only then it is safe to call esp_bt_controller_mem_release(ESP_BT_MODE_CLASSIC_BT) at initialization time to free unused BT Classic memory.

If the mode is ESP_BT_MODE_BTDM, then it may be useful to call API esp_bt_mem_release(ESP_BT_MODE_BTDM) instead, which internally calls esp_bt_controller_mem_release(ESP_BT_MODE_BTDM) and additionally releases the BSS and data consumed by the BT/BLE host stack to heap. For more details about usage please refer to the documentation of esp_bt_mem_release() function

Parameters: mode -- : the mode want to release memory
Returns: ESP_OK - success, other - failed

esp_err_t esp_bt_mem_release(esp_bt_mode_t mode)

esp_bt_mem_release release controller memory and BSS and data section of the BT/BLE host stack as per the mode

This function first releases controller memory by internally calling esp_bt_controller_mem_release(). Additionally, if the mode is set to ESP_BT_MODE_BTDM, it also releases the BSS and data consumed by the BT/BLE host stack to heap

Note that once BT memory is released, the process cannot be reversed. It means you cannot use the bluetooth mode which you have released by this function.

If your firmware will later upgrade the Bluetooth controller mode (BLE -> BT Classic or disabled -> enabled) then do not call this function.

If you never intend to use bluetooth in a current boot-up cycle, you can call esp_bt_mem_release(ESP_BT_MODE_BTDM) before esp_bt_controller_init or after esp_bt_controller_deinit.

For example, if a user only uses bluetooth for setting the WiFi configuration, and does not use bluetooth in the rest of the product operation". In such cases, after receiving the WiFi configuration, you can disable/deinit 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_BTDM);

Parameters: mode -- : the mode whose memory is to be released
Returns: ESP_OK - success, other - failed

int esp_ble_hw_get_static_addr(esp_ble_addr_t *addr)

Returns random static address or -1 if not present.

Returns: ESP_OK - success, other - failed

Structures

struct esp_ble_addr_t

Address type and address value.

Public Members

uint8_t type: Type of the Bluetooth address (public, random, etc.)

uint8_t val[6]: Array containing the 6-byte Bluetooth address value

struct esp_bt_controller_config_t

Controller config options, depend on config mask. Config mask indicate which functions enabled, this means some options or parameters of some functions enabled by config mask.

Public Members

uint32_t config_version: Configuration version

uint16_t ble_ll_resolv_list_size: Size of the BLE resolving list

uint16_t ble_hci_evt_hi_buf_count: Number of high priority HCI event buffers

uint16_t ble_hci_evt_lo_buf_count: Number of low priority HCI event buffers

uint8_t ble_ll_sync_list_cnt: Number of entries in the BLE sync list

uint8_t ble_ll_sync_cnt: Number of BLE sync instances

uint16_t ble_ll_rsp_dup_list_count: Size of the BLE response duplicate list

uint16_t ble_ll_adv_dup_list_count: Size of the BLE advertising duplicate list

uint8_t ble_ll_tx_pwr_dbm: BLE transmit power in dBm

uint64_t rtc_freq: RTC (Real-Time Clock) frequency

uint16_t ble_ll_sca: BLE sleep clock accuracy in ppm

uint8_t ble_ll_scan_phy_number: Number of BLE scanning physical layers

uint16_t ble_ll_conn_def_auth_pyld_tmo: BLE connection default authentication payload timeout

uint8_t ble_ll_jitter_usecs: BLE link layer jitter in microseconds

uint16_t ble_ll_sched_max_adv_pdu_usecs: BLE scheduler maximum advertising PDU duration in microseconds

uint16_t ble_ll_sched_direct_adv_max_usecs: BLE scheduler maximum direct advertising duration in microseconds

uint16_t ble_ll_sched_adv_max_usecs: BLE scheduler maximum advertising duration in microseconds

uint16_t ble_scan_rsp_data_max_len: Maximum length of BLE scan response data

uint8_t ble_ll_cfg_num_hci_cmd_pkts: Number of BLE LL configuration HCI command packets

uint32_t ble_ll_ctrl_proc_timeout_ms: BLE link layer controller process timeout in milliseconds

uint16_t nimble_max_connections: Maximum number of concurrent BLE connections

uint8_t ble_whitelist_size: Size of the BLE whitelist

uint16_t ble_acl_buf_size: Size of the BLE ACL data buffer

uint16_t ble_acl_buf_count: Number of BLE ACL data buffers

uint16_t ble_hci_evt_buf_size: Size of the BLE HCI event buffer

uint16_t ble_multi_adv_instances: Number of BLE multi-advertising instances

uint16_t ble_ext_adv_max_size: Maximum size of BLE extended advertising data

uint16_t controller_task_stack_size: Controller task stack size

uint8_t controller_task_prio: Controller task priority

uint8_t controller_run_cpu: CPU core on which the controller runs

uint8_t enable_qa_test: Enable quality assurance (QA) testing

uint8_t enable_bqb_test: Enable Bluetooth Qualification Test (BQB) testing

uint8_t enable_uart_hci: Enable UART HCI (Host Controller Interface)

uint8_t ble_hci_uart_port: UART port number for Bluetooth HCI

uint32_t ble_hci_uart_baud: Baud rate for Bluetooth HCI UART

uint8_t ble_hci_uart_data_bits: Number of data bits for Bluetooth HCI UART

uint8_t ble_hci_uart_stop_bits: Number of stop bits for Bluetooth HCI UART

uint8_t ble_hci_uart_flow_ctrl: Flow control settings for Bluetooth HCI UART

uint8_t ble_hci_uart_uart_parity: Parity settings for Bluetooth HCI UART

uint8_t enable_tx_cca: Enable Transmit Clear Channel Assessment (TX CCA)

uint8_t cca_rssi_thresh: RSSI threshold for Transmit Clear Channel Assessment (CCA)

uint8_t sleep_en: Enable sleep mode

uint8_t coex_phy_coded_tx_rx_time_limit: PHY coded transmission and reception time limit for coexistence

uint8_t dis_scan_backoff: Disable scan backoff

uint8_t ble_scan_classify_filter_enable: Enable BLE scan classify filter

uint8_t cca_drop_mode: CCA drop mode

int8_t cca_low_tx_pwr: CCA low transmit power

uint8_t main_xtal_freq: Main crystal frequency

uint32_t version_num: Controller configuration version number

uint8_t cpu_freq_mhz: CPU frequency in megahertz (MHz)

uint8_t ignore_wl_for_direct_adv: Ignore the whitelist for direct advertising

uint8_t enable_pcl: Enable power control

uint8_t csa2_select: Select CSA#2

uint32_t config_magic: Magic number for configuration validation

struct esp_vhci_host_callback

esp_vhci_host_callback used for vhci call host function to notify what host need to do

Public Members

void (*notify_host_send_available)(void): callback used to notify that the host can send packet to controller

int (*notify_host_recv)(uint8_t *data, uint16_t len): callback used to notify that the controller has a packet to send to the host

Macros

CONFIG_VERSION

CONFIG_MAGIC

BT_CONTROLLER_INIT_CONFIG_DEFAULT()

Type Definitions

typedef struct esp_vhci_host_callback esp_vhci_host_callback_t: esp_vhci_host_callback used for vhci call host function to notify what host need to do

Enumerations

enum esp_bt_mode_t

Bluetooth mode for controller enable/disable.

Values:

enumerator ESP_BT_MODE_IDLE: Bluetooth is not running

enumerator ESP_BT_MODE_BLE: Run BLE mode

enumerator ESP_BT_MODE_CLASSIC_BT: Run Classic BT mode

enumerator ESP_BT_MODE_BTDM: Run dual mode

enum esp_bt_controller_status_t

Bluetooth controller enable/disable/initialised/de-initialised status.

Values:

enumerator ESP_BT_CONTROLLER_STATUS_IDLE: Controller is in idle state

enumerator ESP_BT_CONTROLLER_STATUS_INITED: Controller is in initialising state

enumerator ESP_BT_CONTROLLER_STATUS_ENABLED: Controller is in enabled state

enumerator ESP_BT_CONTROLLER_STATUS_NUM: Controller is in disabled state

enum esp_ble_power_type_t

BLE tx power type ESP_BLE_PWR_TYPE_CONN_HDL0-8: for each connection, and only be set after connection completed. when disconnect, the correspond TX power is not effected. ESP_BLE_PWR_TYPE_ADV : for advertising/scan response. ESP_BLE_PWR_TYPE_SCAN : for scan. ESP_BLE_PWR_TYPE_DEFAULT : if each connection's TX power is not set, it will use this default value. if neither in scan mode nor in adv mode, it will use this default value. If none of power type is set, system will use ESP_PWR_LVL_P3 as default for ADV/SCAN/CONN0-9.

Values:

enumerator ESP_BLE_PWR_TYPE_CONN_HDL0: For connection handle 0

enumerator ESP_BLE_PWR_TYPE_CONN_HDL1: For connection handle 1

enumerator ESP_BLE_PWR_TYPE_CONN_HDL2: For connection handle 2

enumerator ESP_BLE_PWR_TYPE_CONN_HDL3: For connection handle 3

enumerator ESP_BLE_PWR_TYPE_CONN_HDL4: For connection handle 4

enumerator ESP_BLE_PWR_TYPE_CONN_HDL5: For connection handle 5

enumerator ESP_BLE_PWR_TYPE_CONN_HDL6: For connection handle 6

enumerator ESP_BLE_PWR_TYPE_CONN_HDL7: For connection handle 7

enumerator ESP_BLE_PWR_TYPE_CONN_HDL8: For connection handle 8

enumerator ESP_BLE_PWR_TYPE_ADV: For advertising

enumerator ESP_BLE_PWR_TYPE_SCAN: For scan

enumerator ESP_BLE_PWR_TYPE_DEFAULT: For default, if not set other, it will use default value

enumerator ESP_BLE_PWR_TYPE_NUM: TYPE numbers

enum esp_power_level_t

Bluetooth TX power level(index), it's just a index corresponding to power(dbm).

Values:

enumerator ESP_PWR_LVL_N15: Corresponding to -15dbm

enumerator ESP_PWR_LVL_N12: Corresponding to -12dbm

enumerator ESP_PWR_LVL_N9: Corresponding to -9dbm

enumerator ESP_PWR_LVL_N6: Corresponding to -6dbm

enumerator ESP_PWR_LVL_N3: Corresponding to -3dbm

enumerator ESP_PWR_LVL_N0: Corresponding to 0dbm

enumerator ESP_PWR_LVL_P3: Corresponding to +3dbm

enumerator ESP_PWR_LVL_P6: Corresponding to +6dbm

enumerator ESP_PWR_LVL_P9: Corresponding to +9dbm

enumerator ESP_PWR_LVL_P12: Corresponding to +12dbm

enumerator ESP_PWR_LVL_P15: Corresponding to +15dbm

enumerator ESP_PWR_LVL_P18: Corresponding to +18dbm

enumerator ESP_PWR_LVL_P20: Corresponding to +20dbm

enumerator ESP_PWR_LVL_INVALID: Indicates an invalid value

enum esp_ble_enhanced_power_type_t

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

Values:

enumerator ESP_BLE_ENHANCED_PWR_TYPE_DEFAULT

enumerator ESP_BLE_ENHANCED_PWR_TYPE_ADV

enumerator ESP_BLE_ENHANCED_PWR_TYPE_SCAN

enumerator ESP_BLE_ENHANCED_PWR_TYPE_INIT

enumerator ESP_BLE_ENHANCED_PWR_TYPE_CONN

enumerator ESP_BLE_ENHANCED_PWR_TYPE_MAX

enum esp_ble_log_buf_t

Select buffers.

Values:

enumerator ESP_BLE_LOG_BUF_HCI

enumerator ESP_BLE_LOG_BUF_CONTROLLER

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