Bluetooth HID Host API
Overview
A Bluetooth HID host is a device or software that is capable of connecting and communicating with Bluetooth HID devices, such as keyboards, mice. Users can use the Bluetooth HID Host APIs to send output data or control commands to the HID devices, enabling them to control the behavior or settings of the devices.
Application Example
Check bluetooth folder in ESP-IDF examples, which contains the following application:
- Example bluetooth/esp_hid_host is implemented using the generic esp_hid APIs. esp_hid APIs are build upon the Bluetooth HID APIs and can be a reference. 
API Reference
Header File
Functions
- 
esp_err_t esp_bt_hid_host_register_callback(esp_hh_cb_t callback)
- This function is called to init callbacks with HID host module. - 参数
- callback -- [in] pointer to the init callback function. 
- 返回
- ESP_OK: success 
- other: failed 
 
 
- 
esp_err_t esp_bt_hid_host_init(void)
- This function initializes HID host. This function should be called after esp_bluedroid_enable() and esp_bluedroid_init() success, and should be called after esp_bt_hid_host_register_callback(). When the operation is complete the callback function will be called with ESP_HIDH_INIT_EVT. - 返回
- ESP_OK: success 
- other: failed 
 
 
- 
esp_err_t esp_bt_hid_host_deinit(void)
- Closes the interface. This function should be called after esp_bluedroid_enable() and esp_bluedroid_init() success, and should be called after esp_bt_hid_host_init(). When the operation is complete the callback function will be called with ESP_HIDH_DEINIT_EVT. - 返回
- - ESP_OK: success - other: failed 
 
 
- 
esp_err_t esp_bt_hid_host_connect(esp_bd_addr_t bd_addr)
- Connect to HID device. When the operation is complete the callback function will be called with ESP_HIDH_OPEN_EVT. - 参数
- bd_addr -- [in] Remote device bluetooth device address. 
- 返回
- - ESP_OK: success - other: failed 
 
 
- 
esp_err_t esp_bt_hid_host_disconnect(esp_bd_addr_t bd_addr)
- Disconnect from HID device. When the operation is complete the callback function will be called with ESP_HIDH_CLOSE_EVT. - 参数
- bd_addr -- [in] Remote device bluetooth device address. 
- 返回
- - ESP_OK: success - other: failed 
 
 
- 
esp_err_t esp_bt_hid_host_virtual_cable_unplug(esp_bd_addr_t bd_addr)
- Virtual UnPlug (VUP) the specified HID device. When the operation is complete the callback function will be called with ESP_HIDH_VC_UNPLUG_EVT. - 参数
- bd_addr -- [in] Remote device bluetooth device address. 
- 返回
- - ESP_OK: success - other: failed 
 
 
- 
esp_err_t esp_bt_hid_host_set_info(esp_bd_addr_t bd_addr, esp_hidh_hid_info_t *hid_info)
- Set the HID device descriptor for the specified HID device. When the operation is complete the callback function will be called with ESP_HIDH_SET_INFO_EVT. - 参数
- bd_addr -- [in] Remote device bluetooth device address. 
- hid_info -- [in] HID device descriptor structure. 
 
- 返回
- - ESP_OK: success - other: failed 
 
 
- 
esp_err_t esp_bt_hid_host_get_protocol(esp_bd_addr_t bd_addr)
- Get the HID proto mode. When the operation is complete the callback function will be called with ESP_HIDH_GET_PROTO_EVT. - 参数
- bd_addr -- [in] Remote device bluetooth device address. 
- 返回
- ESP_OK: success 
- other: failed 
 
 
- 
esp_err_t esp_bt_hid_host_set_protocol(esp_bd_addr_t bd_addr, esp_hidh_protocol_mode_t protocol_mode)
- Set the HID proto mode. When the operation is complete the callback function will be called with ESP_HIDH_SET_PROTO_EVT. - 参数
- bd_addr -- [in] Remote device bluetooth device address. 
- protocol_mode -- [in] Protocol mode type. 
 
- 返回
- ESP_OK: success 
- other: failed 
 
 
- 
esp_err_t esp_bt_hid_host_get_idle(esp_bd_addr_t bd_addr)
- Get the HID Idle Time. When the operation is complete the callback function will be called with ESP_HIDH_GET_IDLE_EVT. - 参数
- bd_addr -- [in] Remote device bluetooth device address. 
- 返回
- ESP_OK: success 
- other: failed 
 
 
- 
esp_err_t esp_bt_hid_host_set_idle(esp_bd_addr_t bd_addr, uint16_t idle_time)
- Set the HID Idle Time. When the operation is complete the callback function will be called with ESP_HIDH_SET_IDLE_EVT. - 参数
- bd_addr -- [in] Remote device bluetooth device address. 
- idle_time -- [in] Idle time rate 
 
- 返回
- - ESP_OK: success - other: failed 
 
 
- 
esp_err_t esp_bt_hid_host_get_report(esp_bd_addr_t bd_addr, esp_hidh_report_type_t report_type, uint8_t report_id, int buffer_size)
- Send a GET_REPORT to HID device. When the operation is complete the callback function will be called with ESP_HIDH_GET_RPT_EVT. - 参数
- bd_addr -- [in] Remote device bluetooth device address. 
- report_type -- [in] Report type 
- report_id -- [in] Report id 
- buffer_size -- [in] Buffer size 
 
- 返回
- - ESP_OK: success - other: failed 
 
 
- 
esp_err_t esp_bt_hid_host_set_report(esp_bd_addr_t bd_addr, esp_hidh_report_type_t report_type, uint8_t *report, size_t len)
- Send a SET_REPORT to HID device. When the operation is complete the callback function will be called with ESP_HIDH_SET_RPT_EVT. - 参数
- bd_addr -- [in] Remote device bluetooth device address. 
- report_type -- [in] Report type 
- report -- [in] Report data pointer 
- len -- [in] Report data length 
 
- 返回
- - ESP_OK: success - other: failed 
 
 
- 
esp_err_t esp_bt_hid_host_send_data(esp_bd_addr_t bd_addr, uint8_t *data, size_t len)
- Send data to HID device. When the operation is complete the callback function will be called with ESP_HIDH_DATA_EVT. - 参数
- bd_addr -- [in] Remote device bluetooth device address. 
- data -- [in] Data pointer 
- len -- [in] Data length 
 
- 返回
- - ESP_OK: success - other: failed 
 
 
Unions
- 
union esp_hidh_cb_param_t
- #include <esp_hidh_api.h>HID host callback parameters union. Public Members - 
struct esp_hidh_cb_param_t::hidh_init_evt_param init
- HIDH callback param of ESP_HIDH_INIT_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_uninit_evt_param deinit
- HIDH callback param of ESP_HIDH_DEINIT_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_open_evt_param open
- HIDH callback param of ESP_HIDH_OPEN_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_close_evt_param close
- HIDH callback param of ESP_HIDH_CLOSE_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_unplug_evt_param unplug
- HIDH callback param of ESP_HIDH_VC_UNPLUG_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_get_proto_evt_param get_proto
- HIDH callback param of ESP_HIDH_GET_PROTO_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_set_proto_evt_param set_proto
- HIDH callback param of ESP_HIDH_SET_PROTO_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_get_rpt_evt_param get_rpt
- HIDH callback param of ESP_HIDH_GET_RPT_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_set_rpt_evt_param set_rpt
- HIDH callback param of ESP_HIDH_SET_RPT_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_send_data_evt_param send_data
- HIDH callback param of ESP_HIDH_DATA_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_get_idle_evt_param get_idle
- HIDH callback param of ESP_HIDH_GET_IDLE_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_set_idle_evt_param set_idle
- HIDH callback param of ESP_HIDH_SET_IDLE_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_data_ind_evt_param data_ind
- HIDH callback param of ESP_HIDH_DATA_IND_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_add_dev_evt_param add_dev
- HIDH callback param of ESP_HIDH_ADD_DEV_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_rmv_dev_evt_param rmv_dev
- HIDH callback param of ESP_HIDH_RMV_DEV_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_get_dscp_evt_param dscp
- HIDH callback param of ESP_HIDH_GET_DSCP_EVT 
 - 
struct esp_hidh_cb_param_t::hidh_set_info_evt_param set_info
- HIDH callback param of ESP_HIDH_SET_INFO_EVT 
 - 
struct hidh_add_dev_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_ADD_DEV_EVT. Public Members - 
esp_hidh_status_t status
- operation status 
 - 
uint8_t handle
- device handle 
 - 
esp_bd_addr_t bd_addr
- device address 
 
- 
esp_hidh_status_t status
 - 
struct hidh_close_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_CLOSE_EVT. Public Members - 
esp_hidh_status_t status
- operation status 
 - 
uint8_t reason
- lower layer failed reason(ref hiddefs.h) 
 - 
esp_hidh_connection_state_t conn_status
- connection status 
 - 
uint8_t handle
- device handle 
 
- 
esp_hidh_status_t status
 - 
struct hidh_data_ind_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_DATA_IND_EVT. Public Members - 
esp_hidh_status_t status
- operation status 
 - 
uint8_t handle
- device handle 
 - 
esp_hidh_protocol_mode_t proto_mode
- protocol mode 
 - 
uint16_t len
- data length 
 - 
uint8_t *data
- data pointer 
 
- 
esp_hidh_status_t status
 - 
struct hidh_get_dscp_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_GET_DSCP_EVT. Public Members - 
esp_hidh_status_t status
- operation status 
 - 
uint8_t handle
- device handle 
 - 
bool added
- Indicate if added 
 - 
uint16_t vendor_id
- Vendor ID 
 - 
uint16_t product_id
- Product ID 
 - 
uint16_t version
- Version 
 - 
uint16_t ssr_max_latency
- SSR max latency in slots 
 - 
uint16_t ssr_min_tout
- SSR min timeout in slots 
 - 
uint8_t ctry_code
- Country Code 
 - 
uint16_t dl_len
- Device descriptor length 
 - 
uint8_t *dsc_list
- Device descriptor pointer 
 
- 
esp_hidh_status_t status
 - 
struct hidh_get_idle_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_GET_IDLE_EVT. Public Members - 
esp_hidh_status_t status
- operation status 
 - 
uint8_t handle
- device handle 
 - 
uint8_t idle_rate
- idle rate 
 
- 
esp_hidh_status_t status
 - 
struct hidh_get_proto_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_GET_PROTO_EVT. Public Members - 
esp_hidh_status_t status
- operation status 
 - 
uint8_t handle
- device handle 
 - 
esp_hidh_protocol_mode_t proto_mode
- protocol mode 
 
- 
esp_hidh_status_t status
 - 
struct hidh_get_rpt_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_GET_RPT_EVT. Public Members - 
esp_hidh_status_t status
- operation status 
 - 
uint8_t handle
- device handle 
 - 
uint16_t len
- data length 
 - 
uint8_t *data
- data pointer 
 
- 
esp_hidh_status_t status
 - 
struct hidh_init_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_INIT_EVT. Public Members - 
esp_hidh_status_t status
- status 
 
- 
esp_hidh_status_t status
 - 
struct hidh_open_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_OPEN_EVT. Public Members - 
esp_hidh_status_t status
- operation status 
 - 
esp_hidh_connection_state_t conn_status
- connection status 
 - 
bool is_orig
- indicate if host intiate the connection 
 - 
uint8_t handle
- device handle 
 - 
esp_bd_addr_t bd_addr
- device address 
 
- 
esp_hidh_status_t status
 - 
struct hidh_rmv_dev_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_RMV_DEV_EVT. Public Members - 
esp_hidh_status_t status
- operation status 
 - 
uint8_t handle
- device handle 
 - 
esp_bd_addr_t bd_addr
- device address 
 
- 
esp_hidh_status_t status
 - 
struct hidh_send_data_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_DATA_EVT. Public Members - 
esp_hidh_status_t status
- operation status 
 - 
uint8_t handle
- device handle 
 - 
uint8_t reason
- lower layer failed reason(ref hiddefs.h) 
 
- 
esp_hidh_status_t status
 - 
struct hidh_set_idle_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_SET_IDLE_EVT. 
 - 
struct hidh_set_info_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_SET_INFO_EVT. Public Members - 
esp_hidh_status_t status
- operation status 
 - 
uint8_t handle
- device handle 
 - 
esp_bd_addr_t bd_addr
- device address 
 
- 
esp_hidh_status_t status
 - 
struct hidh_set_proto_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_SET_PROTO_EVT. 
 - 
struct hidh_set_rpt_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_SET_RPT_EVT. 
 - 
struct hidh_uninit_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_DEINIT_EVT. Public Members - 
esp_hidh_status_t status
- status 
 
- 
esp_hidh_status_t status
 - 
struct hidh_unplug_evt_param
- #include <esp_hidh_api.h>ESP_HIDH_VC_UNPLUG_EVT. Public Members - 
esp_hidh_status_t status
- operation status 
 - 
esp_hidh_connection_state_t conn_status
- connection status 
 - 
uint8_t handle
- device handle 
 
- 
esp_hidh_status_t status
 
- 
struct esp_hidh_cb_param_t::hidh_init_evt_param init
Structures
- 
struct esp_hidh_hid_info_t
- HID device information from HID Device Service Record and Device ID Service Record. - Public Members - 
int attr_mask
- device attribute bit mask, refer to esp_hidh_dev_attr_t 
 - 
uint8_t sub_class
- HID device subclass 
 - 
uint8_t app_id
- application ID, refer to esp_hidh_dev_app_id_t 
 - 
int vendor_id
- Device ID information: vendor ID 
 - 
int product_id
- Device ID information: product ID 
 - 
int version
- Device ID information: version 
 - 
uint8_t ctry_code
- SDP attrbutes of HID devices: HID country code (https://www.usb.org/sites/default/files/hid1_11.pdf) 
 - 
int dl_len
- SDP attrbutes of HID devices: HID device descriptor length 
 - 
uint8_t dsc_list[BTHH_MAX_DSC_LEN]
- SDP attrbutes of HID devices: HID device descriptor definition 
 
- 
int attr_mask
Macros
- 
BTHH_MAX_DSC_LEN
- maximum size of HID Device report descriptor 
Type Definitions
- 
typedef void (*esp_hh_cb_t)(esp_hidh_cb_event_t event, esp_hidh_cb_param_t *param)
- HID host callback function type. - Param event
- Event type 
- Param param
- Point to callback parameter, currently is union type 
 
Enumerations
- 
enum esp_hidh_connection_state_t
- HID host connection state. - Values: - 
enumerator ESP_HIDH_CONN_STATE_CONNECTED
- connected state 
 - 
enumerator ESP_HIDH_CONN_STATE_CONNECTING
- connecting state 
 - 
enumerator ESP_HIDH_CONN_STATE_DISCONNECTED
- disconnected state 
 - 
enumerator ESP_HIDH_CONN_STATE_DISCONNECTING
- disconnecting state 
 - 
enumerator ESP_HIDH_CONN_STATE_UNKNOWN
- unknown state (initial state) 
 
- 
enumerator ESP_HIDH_CONN_STATE_CONNECTED
- 
enum esp_hidh_status_t
- HID handshake error code and vendor-defined result code. - Values: - 
enumerator ESP_HIDH_OK
- successful 
 - 
enumerator ESP_HIDH_HS_HID_NOT_READY
- handshake error: device not ready 
 - 
enumerator ESP_HIDH_HS_INVALID_RPT_ID
- handshake error: invalid report ID 
 - 
enumerator ESP_HIDH_HS_TRANS_NOT_SPT
- handshake error: HID device does not support the request 
 - 
enumerator ESP_HIDH_HS_INVALID_PARAM
- handshake error: parameter value does not meet the expected criteria of called function or API 
 - 
enumerator ESP_HIDH_HS_ERROR
- handshake error: HID device could not identify the error condition 
 - 
enumerator ESP_HIDH_ERR
- general ESP HID Host error 
 - 
enumerator ESP_HIDH_ERR_SDP
- SDP error 
 - 
enumerator ESP_HIDH_ERR_PROTO
- SET_PROTOCOL error, only used in ESP_HIDH_OPEN_EVT callback 
 - 
enumerator ESP_HIDH_ERR_DB_FULL
- device database full, used in ESP_HIDH_OPEN_EVT/ESP_HIDH_ADD_DEV_EVT 
 - 
enumerator ESP_HIDH_ERR_TOD_UNSPT
- type of device not supported 
 - 
enumerator ESP_HIDH_ERR_NO_RES
- out of system resources 
 - 
enumerator ESP_HIDH_ERR_AUTH_FAILED
- authentication fail 
 - 
enumerator ESP_HIDH_ERR_HDL
- connection handle error 
 - 
enumerator ESP_HIDH_ERR_SEC
- encryption error 
 - 
enumerator ESP_HIDH_BUSY
- vendor-defined: temporarily can not handle this request 
 - 
enumerator ESP_HIDH_NO_DATA
- vendor-defined: no data. 
 - 
enumerator ESP_HIDH_NEED_INIT
- vendor-defined: HIDH module shall initialize first 
 - 
enumerator ESP_HIDH_NEED_DEINIT
- vendor-defined: HIDH module shall de-deinitialize first 
 - 
enumerator ESP_HIDH_NO_CONNECTION
- vendor-defined: connection may have been closed 
 
- 
enumerator ESP_HIDH_OK
- 
enum esp_hidh_protocol_mode_t
- HID host protocol modes. - Values: - 
enumerator ESP_HIDH_BOOT_MODE
- boot protocol mode 
 - 
enumerator ESP_HIDH_REPORT_MODE
- report protocol mode 
 - 
enumerator ESP_HIDH_UNSUPPORTED_MODE
- unsupported protocol mode 
 
- 
enumerator ESP_HIDH_BOOT_MODE
- 
enum esp_hidh_report_type_t
- HID host report types. - Values: - 
enumerator ESP_HIDH_REPORT_TYPE_OTHER
- unsupported report type 
 - 
enumerator ESP_HIDH_REPORT_TYPE_INPUT
- input report type 
 - 
enumerator ESP_HIDH_REPORT_TYPE_OUTPUT
- output report type 
 - 
enumerator ESP_HIDH_REPORT_TYPE_FEATURE
- feature report type 
 
- 
enumerator ESP_HIDH_REPORT_TYPE_OTHER
- 
enum esp_hidh_cb_event_t
- HID host callback function events. - Values: - 
enumerator ESP_HIDH_INIT_EVT
- when HID host is initialized, the event comes 
 - 
enumerator ESP_HIDH_DEINIT_EVT
- when HID host is deinitialized, the event comes 
 - 
enumerator ESP_HIDH_OPEN_EVT
- when HID host connection opened, the event comes 
 - 
enumerator ESP_HIDH_CLOSE_EVT
- when HID host connection closed, the event comes 
 - 
enumerator ESP_HIDH_GET_RPT_EVT
- when Get_Report command is called, the event comes 
 - 
enumerator ESP_HIDH_SET_RPT_EVT
- when Set_Report command is called, the event comes 
 - 
enumerator ESP_HIDH_GET_PROTO_EVT
- when Get_Protocol command is called, the event comes 
 - 
enumerator ESP_HIDH_SET_PROTO_EVT
- when Set_Protocol command is called, the event comes 
 - 
enumerator ESP_HIDH_GET_IDLE_EVT
- when Get_Idle command is called, the event comes 
 - 
enumerator ESP_HIDH_SET_IDLE_EVT
- when Set_Idle command is called, the event comes 
 - 
enumerator ESP_HIDH_GET_DSCP_EVT
- when HIDH is initialized, the event comes 
 - 
enumerator ESP_HIDH_ADD_DEV_EVT
- when a device is added, the event comes 
 - 
enumerator ESP_HIDH_RMV_DEV_EVT
- when a device is removed, the event comes 
 - 
enumerator ESP_HIDH_VC_UNPLUG_EVT
- when virtually unplugged, the event comes 
 - 
enumerator ESP_HIDH_DATA_EVT
- when send data on interrupt channel, the event comes 
 - 
enumerator ESP_HIDH_DATA_IND_EVT
- when receive data on interrupt channel, the event comes 
 - 
enumerator ESP_HIDH_SET_INFO_EVT
- when set the HID device descriptor, the event comes 
 
- 
enumerator ESP_HIDH_INIT_EVT
- 
enum esp_hidh_dev_attr_t
- HID device information from HID Device Service Record and Device ID Service Record. - Values: - 
enumerator ESP_HIDH_DEV_ATTR_VIRTUAL_CABLE
- whether Virtual Cables is supported 
 - 
enumerator ESP_HIDH_DEV_ATTR_NORMALLY_CONNECTABLE
- whether device is in Page Scan mode when there is no active connection 
 - 
enumerator ESP_HIDH_DEV_ATTR_RECONNECT_INITIATE
- whether the HID device inititates the reconnection process 
 
- 
enumerator ESP_HIDH_DEV_ATTR_VIRTUAL_CABLE
- 
enum esp_hidh_dev_app_id_t
- application ID(non-zero) for each type of device - Values: - 
enumerator ESP_HIDH_APP_ID_MOUSE
- pointing device 
 - 
enumerator ESP_HIDH_APP_ID_KEYBOARD
- keyboard 
 - 
enumerator ESP_HIDH_APP_ID_REMOTE_CONTROL
- remote control 
 - 
enumerator ESP_HIDH_APP_ID_JOYSTICK
- joystick 
 - 
enumerator ESP_HIDH_APP_ID_GAMEPAD
- gamepad 
 
- 
enumerator ESP_HIDH_APP_ID_MOUSE