xref: /docs/en/application-dev/reference/apis-driverdevelopment-kit/_hid_ddk.md (revision e41f4b71)

# HID DDK


## Overview

Provides HID driver development kit (DDK) functions, including those for creating a device, sending events to a device, and destroying a device.

**System capability**: SystemCapability.Driver.HID.Extension

**Since**

11

## Summary


### Files

| Name| Description| 
| -------- | -------- |
| [hid_ddk_api.h](hid__ddk__api_8h.md) | Declares the HID DDK functions for accessing an input device from the host.<br>File to include: &lt;hid/hid_ddk_api.h&gt;<br>Library: libhid.z.so| 
| [hid_ddk_types.h](hid__ddk__types_8h.md) | Defines the enum variables and structs used in the HID DDK.<br>File to include: &lt;hid/hid_ddk_types.h&gt;<br>Library: libhid.z.so | 


### Structs

| Name| Description| 
| -------- | -------- |
| [Hid_EmitItem](_hid___emit_item.md) | Defines event information. | 
| [Hid_Device](_hid___device.md) | Defines basic device information. | 
| [Hid_EventTypeArray](_hid___event_type_array.md) | Defines an array of event types. | 
| [Hid_KeyCodeArray](_hid___key_code_array.md) | Defines an array of key codes. | 
| [Hid_AbsAxesArray](_hid___abs_axes_array.md) | Defines an array of absolute coordinates. | 
| [Hid_RelAxesArray](_hid___rel_axes_array.md) | Defines an array of relative coordinates. | 
| [Hid_MscEventArray](_hid___msc_event_array.md) | Defines an array of miscellaneous events. | 
| [Hid_EventProperties](_hid___event_properties.md) | Defines the event properties of a device. | 


### Types

| Name| Description| 
| -------- | -------- |
| [Hid_EmitItem](#hid_emititem) | Defines a struct for event information. | 
| [Hid_Device](#hid_device) | Defines a struct for basic device information. | 
| [Hid_EventTypeArray](#hid_eventtypearray) | Defines a struct for an array of event types. | 
| [Hid_KeyCodeArray](#hid_keycodearray) | Defines a struct for an array of key codes. | 
| [Hid_AbsAxesArray](#hid_absaxesarray) | Defines a struct for an array of absolute coordinates. | 
| [Hid_RelAxesArray](#hid_relaxesarray) | Defines a struct for an array of relative coordinates. | 
| [Hid_MscEventArray](#hid_msceventarray) | Defines a struct for an array of miscellaneous events. | 
| [Hid_EventProperties](#hid_eventproperties) | Defines a struct for the event properties of a device. | 


### Enums

| Name| Description| 
| -------- | -------- |
| [Hid_DeviceProp](#hid_deviceprop) {<br>HID_PROP_POINTER = 0x00, HID_PROP_DIRECT = 0x01, HID_PROP_BUTTON_PAD = 0x02, HID_PROP_SEMI_MT = 0x03,<br>HID_PROP_TOP_BUTTON_PAD = 0x04, HID_PROP_POINTING_STICK = 0x05, HID_PROP_ACCELEROMETER = 0x06<br>} | Enumerates the properties of input devices. | 
| [Hid_EventType](#hid_eventtype) {<br>HID_EV_SYN = 0x00, HID_EV_KEY = 0x01, HID_EV_REL = 0x02, HID_EV_ABS = 0x03,<br>HID_EV_MSC = 0x04<br>} | Enumerates the event types. | 
| [Hid_SynEvent](#hid_synevent) { HID_SYN_REPORT = 0, HID_SYN_CONFIG = 1, HID_SYN_MT_REPORT = 2, HID_SYN_DROPPED = 3 } | Enumerates sync events. | 
| [Hid_KeyCode](#hid_keycode) {<br>HID_KEY_A = 30, HID_KEY_B = 48, HID_KEY_C = 46, HID_KEY_D = 32,<br>HID_KEY_E = 18, HID_KEY_F = 33, HID_KEY_G = 34, HID_KEY_H = 35,<br>HID_KEY_I = 23, HID_KEY_J = 36, HID_KEY_K = 37, HID_KEY_L = 38,<br>HID_KEY_M = 50, HID_KEY_N = 49, HID_KEY_O = 24, HID_KEY_P = 25,<br>HID_KEY_Q = 16, HID_KEY_R = 19, HID_KEY_S = 31, HID_KEY_T = 20,<br>HID_KEY_U = 22, HID_KEY_V = 47, HID_KEY_W = 17, HID_KEY_X = 45,<br>HID_KEY_Y = 21, HID_KEY_Z = 44, HID_KEY_ESC = 1, HID_KEY_0 = 11,<br>HID_KEY_1 = 2, HID_KEY_2 = 3, HID_KEY_3 = 4, HID_KEY_4 = 5,<br>HID_KEY_5 = 6, HID_KEY_6 = 7, HID_KEY_7 = 8, HID_KEY_8 = 9,<br>HID_KEY_9 = 10, HID_KEY_GRAVE = 41, HID_KEY_MINUS = 12, HID_KEY_EQUALS = 13,<br>HID_KEY_BACKSPACE = 14, HID_KEY_LEFT_BRACKET = 26, HID_KEY_RIGHT_BRACKET = 27, HID_KEY_ENTER = 28,<br>HID_KEY_LEFT_SHIFT = 42, HID_KEY_BACKSLASH = 43, HID_KEY_SEMICOLON = 39, HID_KEY_APOSTROPHE = 40,<br>HID_KEY_SPACE = 57, HID_KEY_SLASH = 53, HID_KEY_COMMA = 51, HID_KEY_PERIOD = 52,<br>HID_KEY_RIGHT_SHIFT = 54, HID_KEY_NUMPAD_0 = 82, HID_KEY_NUMPAD_1 = 79, HID_KEY_NUMPAD_2 = 80,<br>HID_KEY_NUMPAD_3 = 81, HID_KEY_NUMPAD_4 = 75, HID_KEY_NUMPAD_5 = 76, HID_KEY_NUMPAD_6 = 77,<br>HID_KEY_NUMPAD_7 = 71, HID_KEY_NUMPAD_8 = 72, HID_KEY_NUMPAD_9 = 73, HID_KEY_NUMPAD_DIVIDE = 70,<br>HID_KEY_NUMPAD_MULTIPLY = 55, HID_KEY_NUMPAD_SUBTRACT = 74, HID_KEY_NUMPAD_ADD = 78, HID_KEY_NUMPAD_DOT = 83,<br>HID_KEY_SYSRQ = 99, HID_KEY_MUTE = 113, HID_KEY_VOLUME_DOWN = 114, HID_KEY_VOLUME_UP = 115,<br>HID_KEY_BRIGHTNESS_DOWN = 224, HID_KEY_BRIGHTNESS_UP = 225, HID_BTN_0 = 0x100, HID_BTN_1 = 0x101,<br>HID_BTN_2 = 0x102, HID_BTN_3 = 0x103, HID_BTN_4 = 0x104, HID_BTN_5 = 0x105,<br>HID_BTN_6 = 0x106, HID_BTN_7 = 0x107, HID_BTN_8 = 0x108, HID_BTN_9 = 0x109,<br>HID_BTN_LEFT = 0x110, HID_BTN_RIGHT = 0x111, HID_BTN_MIDDLE = 0x112, HID_BTN_SIDE = 0x113,<br>HID_BTN_EXTRA = 0x114, HID_BTN_FORWARD = 0x115, HID_BTN_BACKWARD = 0x116, HID_BTN_TASK = 0x117,<br>HID_BTN_TOOL_PEN = 0x140, HID_BTN_TOOL_RUBBER = 0x141, HID_BTN_TOOL_BRUSH = 0x142, HID_BTN_TOOL_PENCIL = 0x143,<br>HID_BTN_TOOL_AIRBRUSH = 0x144, HID_BTN_TOOL_FINGER = 0x145, HID_BTN_TOOL_MOUSE = 0x146, HID_BTN_TOOL_LENS = 0x147,<br>HID_BTN_TOOL_QUINT_TAP = 0x148, HID_BTN_STYLUS3 = 0x149, HID_BTN_TOUCH = 0x14a, HID_BTN_STYLUS = 0x14b,<br>HID_BTN_STYLUS2 = 0x14c, HID_BTN_TOOL_DOUBLE_TAP = 0x14d, HID_BTN_TOOL_TRIPLE_TAP = 0x14e, HID_BTN_TOOL_QUAD_TAP = 0x14f,<br>HID_BTN_WHEEL = 0x150<br>} | Enumerates the key codes. | 
| [Hid_AbsAxes](#hid_absaxes) {<br>HID_ABS_X = 0x00, HID_ABS_Y = 0x01, HID_ABS_Z = 0x02, HID_ABS_RX = 0x03,<br>HID_ABS_RY = 0x04, HID_ABS_RZ = 0x05, HID_ABS_THROTTLE = 0x06, HID_ABS_RUDDER = 0x07,<br>HID_ABS_WHEEL = 0x08, HID_ABS_GAS = 0x09, HID_ABS_BRAKE = 0x0a, HID_ABS_HAT0X = 0x10,<br>HID_ABS_HAT0Y = 0x11, HID_ABS_HAT1X = 0x12, HID_ABS_HAT1Y = 0x13, HID_ABS_HAT2X = 0x14,<br>HID_ABS_HAT2Y = 0x15, HID_ABS_HAT3X = 0x16, HID_ABS_HAT3Y = 0x17, HID_ABS_PRESSURE = 0x18,<br>HID_ABS_DISTANCE = 0x19, HID_ABS_TILT_X = 0x1a, HID_ABS_TILT_Y = 0x1b, HID_ABS_TOOL_WIDTH = 0x1c,<br>HID_ABS_VOLUME = 0x20, HID_ABS_MISC = 0x28<br>} | Enumerates the absolute coordinates. | 
| [Hid_RelAxes](#hid_relaxes) {<br>HID_REL_X = 0x00, HID_REL_Y = 0x01, HID_REL_Z = 0x02, HID_REL_RX = 0x03,<br>HID_REL_RY = 0x04, HID_REL_RZ = 0x05, HID_REL_HWHEEL = 0x06, HID_REL_DIAL = 0x07,<br>HID_REL_WHEEL = 0x08, HID_REL_MISC = 0x09, HID_REL_RESERVED = 0x0a, HID_REL_WHEEL_HI_RES = 0x0b,<br>HID_REL_HWHEEL_HI_RES = 0x0c<br>} | Enumerates the relative coordinates. | 
| [Hid_MscEvent](#hid_mscevent) {<br>HID_MSC_SERIAL = 0x00, HID_MSC_PULSE_LED = 0x01, HID_MSC_GESTURE = 0x02, HID_MSC_RAW = 0x03,<br>HID_MSC_SCAN = 0x04, HID_MSC_TIMESTAMP = 0x05<br>} | Enumerates miscellaneous input events. | 
| [Hid_DdkErrCode](#hid_ddkerrcode) {<br>HID_DDK_SUCCESS = 0, HID_DDK_FAILURE = -1, HID_DDK_INVALID_PARAMETER = -2, HID_DDK_INVALID_OPERATION = -3,<br>HID_DDK_NULL_PTR = -4, HID_DDK_TIMEOUT = -5, HID_DDK_NO_PERM = -6<br>} | Enumerates the HID DDK error codes. | 


### Functions

| Name| Description| 
| -------- | -------- |
| [OH_Hid_CreateDevice](#oh_hid_createdevice) ([Hid_Device](_hid___device.md) \*hidDevice, [Hid_EventProperties](_hid___event_properties.md) \*hidEventProperties) | Creates a device. | 
| [OH_Hid_EmitEvent](#oh_hid_emitevent) (int32_t deviceId, const [Hid_EmitItem](_hid___emit_item.md) items[], uint16_t length) | Sends an event list to a device. | 
| [OH_Hid_DestroyDevice](#oh_hid_destroydevice) (int32_t deviceId) | Destroys a device. | 


### Variables

| Name| Description| 
| -------- | -------- |
| [Hid_EmitItem::type](#type) | Event type. | 
| [Hid_EmitItem::code](#code) | Event code. | 
| [Hid_EmitItem::value](#value) | Event value. | 
| [Hid_Device::deviceName](#devicename) | Device name. | 
| [Hid_Device::vendorId](#vendorid) | Vendor ID. | 
| [Hid_Device::productId](#productid) | Product ID. | 
| [Hid_Device::version](#version) | Version number. | 
| [Hid_Device::bustype](#bustype) | Bus type. | 
| [Hid_Device::properties](#properties) | Device properties. | 
| [Hid_Device::propLength](#proplength) | Number of device properties. | 
| [Hid_EventTypeArray::hidEventType](#hideventtype) | Event type. | 
| [Hid_EventTypeArray::length](#length-15) | Array length. | 
| [Hid_KeyCodeArray::hidKeyCode](#hidkeycode) | key code. | 
| [Hid_KeyCodeArray::length](#length-25) | Array length. | 
| [Hid_AbsAxesArray::hidAbsAxes](#hidabsaxes) | Array of absolute coordinates. | 
| [Hid_AbsAxesArray::length](#length-35) | Array length. | 
| [Hid_RelAxesArray::hidRelAxes](#hidrelaxes) | Array of relative coordinates. | 
| [Hid_RelAxesArray::length](#length-45) | Array length. | 
| [Hid_MscEventArray::hidMscEvent](#hidmscevent) | Miscellaneous event. | 
| [Hid_MscEventArray::length](#length-55) | Array length. | 
| [Hid_EventProperties::hidEventTypes](#hideventtypes) | Array of event types. | 
| [Hid_EventProperties::hidKeys](#hidkeys) | Array of key codes. | 
| [Hid_EventProperties::hidAbs](#hidabs) | Array of absolute coordinate properties. | 
| [Hid_EventProperties::hidRelBits](#hidrelbits) | Array of relative coordinate properties. | 
| [Hid_EventProperties::hidMiscellaneous](#hidmiscellaneous) | Array of miscellaneous events. | 
| [Hid_EventProperties::hidAbsMax](#hidabsmax) [64] | Maximum values of the absolute coordinates. | 
| [Hid_EventProperties::hidAbsMin](#hidabsmin) [64] | Minimum values of the absolute coordinates. | 
| [Hid_EventProperties::hidAbsFuzz](#hidabsfuzz) [64] | Fuzzy values of the absolute coordinates. | 
| [Hid_EventProperties::hidAbsFlat](#hidabsflat) [64] | Fixed values of the absolute coordinates. | 


## Type Description


### Hid_AbsAxesArray

```
typedef struct Hid_AbsAxesArrayHid_AbsAxesArray
```
**Description**
Defines a struct for an array of absolute coordinates.

**Since**: 11


### Hid_Device

```
typedef struct Hid_DeviceHid_Device
```
**Description**
Defines a struct for basic device information.

**Since**: 11


### Hid_EmitItem

```
typedef struct Hid_EmitItemHid_EmitItem
```
**Description**
Defines a struct for event information.

**Since**: 11


### Hid_EventProperties

```
typedef struct Hid_EventPropertiesHid_EventProperties
```
**Description**
Defines a struct for the event properties of a device.

**Since**: 11


### Hid_EventTypeArray

```
typedef struct Hid_EventTypeArrayHid_EventTypeArray
```
**Description**
Defines a struct for an array of event types.

**Since**: 11


### Hid_KeyCodeArray

```
typedef struct Hid_KeyCodeArrayHid_KeyCodeArray
```
**Description**
Defines a struct for an array of key codes.

**Since**: 11


### Hid_MscEventArray

```
typedef struct Hid_MscEventArrayHid_MscEventArray
```
**Description**
Defines a struct for an array of miscellaneous events.

**Since**: 11


### Hid_RelAxesArray

```
typedef struct Hid_RelAxesArrayHid_RelAxesArray
```
**Description**
Defines a struct for an array of relative coordinates.

**Since**: 11


## Enum Description


### Hid_AbsAxes

```
enum Hid_AbsAxes
```
**Description**
Enumerates the absolute coordinates.

**Since**: 11

| Value| Description| 
| -------- | -------- |
| HID_ABS_X  | X axis.| 
| HID_ABS_Y  | Y axis.| 
| HID_ABS_Z  | Z axis.| 
| HID_ABS_RX  | X axis of the right analog stick.| 
| HID_ABS_RY  | Y axis of the right analog stick.| 
| HID_ABS_RZ  | Z axis of the right analog stick.| 
| HID_ABS_THROTTLE  | Throttle.| 
| HID_ABS_RUDDER  | Rudder.| 
| HID_ABS_WHEEL  | Scroll wheel.| 
| HID_ABS_GAS  | Gas.| 
| HID_ABS_BRAKE  | Brake.| 
| HID_ABS_HAT0X  | HAT0X | 
| HID_ABS_HAT0Y  | HAT0Y | 
| HID_ABS_HAT1X  | HAT1X | 
| HID_ABS_HAT1Y  | HAT1Y | 
| HID_ABS_HAT2X  | HAT2X | 
| HID_ABS_HAT2Y  | HAT2Y | 
| HID_ABS_HAT3X  | HAT3X | 
| HID_ABS_HAT3Y  | HAT3Y | 
| HID_ABS_PRESSURE  | Pressure.| 
| HID_ABS_DISTANCE  | Distance.| 
| HID_ABS_TILT_X  | Tilt of X axis.| 
| HID_ABS_TILT_Y  | Tilt of Y axis.| 
| HID_ABS_TOOL_WIDTH  | Width of the touch tool.| 
| HID_ABS_VOLUME  | Volume.| 
| HID_ABS_MISC  | Others.| 


### Hid_DdkErrCode

```
enum Hid_DdkErrCode
```
**Description**
Enumerates the HID DDK error codes.

**Since**: 11

| Value| Description| 
| -------- | -------- |
| HID_DDK_SUCCESS  | Operation successful.| 
| HID_DDK_FAILURE  | Operation failed.| 
| HID_DDK_INVALID_PARAMETER  | Invalid parameter.| 
| HID_DDK_INVALID_OPERATION  | Invalid operation.| 
| HID_DDK_NULL_PTR  | Null pointer.| 
| HID_DDK_TIMEOUT  | Timeout.| 
| HID_DDK_NO_PERM  | Permission denied.| 


### Hid_DeviceProp

```
enum Hid_DeviceProp
```
**Description**
Enumerates the properties of input devices.

**Since**: 11

| Value| Description| 
| -------- | -------- |
| HID_PROP_POINTER  | Pointer device.| 
| HID_PROP_DIRECT  | Direct input device.| 
| HID_PROP_BUTTON_PAD  | Touch device with bottom keys.| 
| HID_PROP_SEMI_MT  | Full multi-touch device.| 
| HID_PROP_TOP_BUTTON_PAD  | Touch device with top soft keys.| 
| HID_PROP_POINTING_STICK  | Pointing stick.| 
| HID_PROP_ACCELEROMETER  | Accelerometer.| 


### Hid_EventType

```
enum Hid_EventType
```
**Description**
Enumerates the event types.

**Since**: 11

| Value| Description| 
| -------- | -------- |
| HID_EV_SYN  | Sync event.| 
| HID_EV_KEY  | Key event.| 
| HID_EV_REL  | Relative coordinate event.| 
| HID_EV_ABS  | Absolute coordinate event.| 
| HID_EV_MSC  |  Miscellaneous event.| 


### Hid_KeyCode

```
enum Hid_KeyCode
```
**Description**
Enumerates the key codes.

**Since**: 11

| Value| Description| 
| -------- | -------- |
| HID_KEY_A  | Key A.| 
| HID_KEY_B  | Key B.| 
| HID_KEY_C  | Key C.| 
| HID_KEY_D  | Key D.| 
| HID_KEY_E  | Key E.| 
| HID_KEY_F  | Key F.| 
| HID_KEY_G  | Key G.| 
| HID_KEY_H  | Key H.| 
| HID_KEY_I  | Key I.| 
| HID_KEY_J  | Key J.| 
| HID_KEY_K  | Key K.| 
| HID_KEY_L  | Key L.| 
| HID_KEY_M  | Key M.| 
| HID_KEY_N  | Key N.| 
| HID_KEY_O  | Key O.| 
| HID_KEY_P  | Key P.| 
| HID_KEY_Q  | Key Q.| 
| HID_KEY_R  | Key R.| 
| HID_KEY_S  | Key S.| 
| HID_KEY_T  | Key T.| 
| HID_KEY_U  | Key U.| 
| HID_KEY_V  | Key V.| 
| HID_KEY_W  | Key W.| 
| HID_KEY_X  | Key X.| 
| HID_KEY_Y  | Key Y.| 
| HID_KEY_Z  | Key Z.| 
| HID_KEY_ESC  | Key Esc.| 
| HID_KEY_0  | Key 0.| 
| HID_KEY_1  | Key 1.| 
| HID_KEY_2  | Key 2.| 
| HID_KEY_3  | Key 3.| 
| HID_KEY_4  | Key 4.| 
| HID_KEY_5  | Key 5.| 
| HID_KEY_6  | Key 6.| 
| HID_KEY_7  | Key 7.| 
| HID_KEY_8  | Key 8.| 
| HID_KEY_9  | Key 9.| 
| HID_KEY_GRAVE  | Key grave (`).| 
| HID_KEY_MINUS  | Key minus (-).| 
| HID_KEY_EQUALS  | Key equals (=).| 
| HID_KEY_BACKSPACE  | key Backspace.| 
| HID_KEY_LEFT_BRACKET  | Key left bracket ([).| 
| HID_KEY_RIGHT_BRACKET  | Key right bracket (]).| 
| HID_KEY_ENTER  | Key Enter.| 
| HID_KEY_LEFT_SHIFT  | Left Shift.| 
| HID_KEY_BACKSLASH  | Key backslash (\).| 
| HID_KEY_SEMICOLON  | Key semicolon (;).| 
| HID_KEY_APOSTROPHE  | Key apostrophe (').| 
| HID_KEY_SPACE  | Key Space.| 
| HID_KEY_SLASH  | Key slash (/).| 
| HID_KEY_COMMA  | Key comma (,).| 
| HID_KEY_PERIOD  | Key period (.).| 
| HID_KEY_RIGHT_SHIFT  | Right Shift.| 
| HID_KEY_NUMPAD_0  | Numeral 0 on the numeric keypad.| 
| HID_KEY_NUMPAD_1  | Numeral 1 on the numeric keypad.| 
| HID_KEY_NUMPAD_2  | Numeral 2 on the numeric keypad.| 
| HID_KEY_NUMPAD_3  | Numeral 3 on the numeric keypad.| 
| HID_KEY_NUMPAD_4  | Numeral 4 on the numeric keypad.| 
| HID_KEY_NUMPAD_5  | Numeral 5 on the numeric keypad.| 
| HID_KEY_NUMPAD_6  | Numeral 6 on the numeric keypad.| 
| HID_KEY_NUMPAD_7  | Numeral 7 on the numeric keypad.| 
| HID_KEY_NUMPAD_8  | Numeral 8 on the numeric keypad.| 
| HID_KEY_NUMPAD_9  | Numeral 9 on the numeric keypad.| 
| HID_KEY_NUMPAD_DIVIDE  | Arithmetic operator / (division) on the numeric keypad.| 
| HID_KEY_NUMPAD_MULTIPLY  | Arithmetic operator * (multiplication) on the numeric keypad.| 
| HID_KEY_NUMPAD_SUBTRACT  | Arithmetic operator - (subtraction) on the numeric keypad.| 
| HID_KEY_NUMPAD_ADD  | Arithmetic operator + (addition) on the numeric keypad.| 
| HID_KEY_NUMPAD_DOT  | Decimal point (.) on the numeric keypad. | 
| HID_KEY_SYSRQ  | Key **Print Screen**.| 
| HID_KEY_MUTE  | Mute key.| 
| HID_KEY_VOLUME_DOWN  | Key for decreasing volume.| 
| HID_KEY_VOLUME_UP  | Key for increasing volume.| 
| HID_KEY_BRIGHTNESS_DOWN  | Key for making the screen dimmer.| 
| HID_KEY_BRIGHTNESS_UP  | Key for making the screen brighter.| 
| HID_BTN_0  | Button 0.| 
| HID_BTN_1  | Button 1| 
| HID_BTN_2  | Button 2.| 
| HID_BTN_3  | Button 3.| 
| HID_BTN_4  | Button 4.| 
| HID_BTN_5  | Button 5.| 
| HID_BTN_6  | Button 6.| 
| HID_BTN_7  | Button 7.| 
| HID_BTN_8  | Button 8.| 
| HID_BTN_9  | Button 9.| 
| HID_BTN_LEFT  | Left mouse button.| 
| HID_BTN_RIGHT  | Right mouse button.| 
| HID_BTN_MIDDLE  | Middle mouse button.| 
| HID_BTN_SIDE  | Side mouse button.| 
| HID_BTN_EXTRA  | Extra mouse button.| 
| HID_BTN_FORWARD  | Mouse forward button.| 
| HID_BTN_BACKWARD  | Mouse backward button.| 
| HID_BTN_TASK  | Mouse task button.| 
| HID_BTN_TOOL_PEN  | Pen.| 
| HID_BTN_TOOL_RUBBER  | Eraser.| 
| HID_BTN_TOOL_BRUSH  | Brush.| 
| HID_BTN_TOOL_PENCIL  | Pencil.| 
| HID_BTN_TOOL_AIRBRUSH  | Air brush.| 
| HID_BTN_TOOL_FINGER  | Finger.| 
| HID_BTN_TOOL_MOUSE  | Mouse.| 
| HID_BTN_TOOL_LENS  | Lens.| 
| HID_BTN_TOOL_QUINT_TAP  | Five-finger touch.| 
| HID_BTN_STYLUS3  | Stylus 3.| 
| HID_BTN_TOUCH  | Touch.| 
| HID_BTN_STYLUS  | Stylus.| 
| HID_BTN_STYLUS2  | Stylus 2.| 
| HID_BTN_TOOL_DOUBLE_TAP  | Two-finger touch.| 
| HID_BTN_TOOL_TRIPLE_TAP  | Three-finger touch.| 
| HID_BTN_TOOL_QUAD_TAP  | Four-finger touch.| 
| HID_BTN_WHEEL  | Scroll wheel.| 


### Hid_MscEvent

```
enum Hid_MscEvent
```
**Description**
Enumerates miscellaneous input events.

**Since**: 11

| Value| Description| 
| -------- | -------- |
| HID_MSC_SERIAL  | Serial number.| 
| HID_MSC_PULSE_LED  | Pulse.| 
| HID_MSC_GESTURE  | Gesture.| 
| HID_MSC_RAW  | Start event.| 
| HID_MSC_SCAN  | Scan.| 
| HID_MSC_TIMESTAMP  | Timestamp.| 


### Hid_RelAxes

```
enum Hid_RelAxes
```
**Description**
Enumerates the relative coordinates.

**Since**: 11

| Value| Description| 
| -------- | -------- |
| HID_REL_X  | X axis.| 
| HID_REL_Y  | Y axis.| 
| HID_REL_Z  | Z axis.| 
| HID_REL_RX  | X axis of the right analog stick.| 
| HID_REL_RY  | Y axis of the right analog stick.| 
| HID_REL_RZ  | Z axis of the right analog stick.| 
| HID_REL_HWHEEL  | Horizontal scroll wheel.| 
| HID_REL_DIAL  | Scale.| 
| HID_REL_WHEEL  | Scroll wheel.| 
| HID_REL_MISC  | Others.| 
| HID_REL_RESERVED  | Reserved.| 
| HID_REL_WHEEL_HI_RES  | High-resolution scroll wheel.| 
| HID_REL_HWHEEL_HI_RES  | High-resolution horizontal scroll wheel.| 


### Hid_SynEvent

```
enum Hid_SynEvent
```
**Description**
Enumerates sync events.

**Since**: 11

| Value| Description| 
| -------- | -------- |
| HID_SYN_REPORT  | Indicates the end of an event.| 
| HID_SYN_CONFIG  | Indicates configuration synchronization.| 
| HID_SYN_MT_REPORT  | Indicates the end of a multi-touch ABS data packet.| 
| HID_SYN_DROPPED  | Indicates that the event is discarded.| 


## Function Description


### OH_Hid_CreateDevice()

```
int32_t OH_Hid_CreateDevice (Hid_Device * hidDevice, Hid_EventProperties * hidEventProperties )
```
**Description**
Creates a device.

**Since**: 11

**Parameters**

| Name| Description| 
| -------- | -------- |
| hidDevice | Pointer to the basic information about the device to create, including the device name, vendor ID, and product ID. | 
| hidEventProperties | Pointer to the event properties related to the device to create, including the event type, key event properties, absolute coordinate event properties, and relative coordinate event properties. | 

**Required Permissions**

ohos.permission.ACCESS_DDK_HID

**Returns**

Returns the device ID (a non-negative number) if the operation is successful; returns a negative number otherwise.


### OH_Hid_DestroyDevice()

```
int32_t OH_Hid_DestroyDevice (int32_t deviceId)
```
**Description**
Destroys a device.

**Since**: 11

**Parameters**

| Name| Description| 
| -------- | -------- |
| deviceId | ID of the device to destroy. | 

**Required Permissions**

ohos.permission.ACCESS_DDK_HID

**Returns**

Returns **0** if the operation is successful; returns a negative value otherwise.


### OH_Hid_EmitEvent()

```
int32_t OH_Hid_EmitEvent (int32_t deviceId, const Hid_EmitItem items[], uint16_t length )
```
**Description**
Sends an event list to a device.

**Since**: 11

**Parameters**

| Name| Description| 
| -------- | -------- |
| deviceId | ID of the target device. | 
| items | List of the events to send. The event information includes the event type (**Hid_EventType**), code (**Hid_SynEvent**, **Hid_KeyCode**, **HidBtnCode**, **Hid_AbsAxes**, **Hid_RelAxes**, or **Hid_MscEvent**), and value (depending on the actual device input). | 
| length | Length of the event list (number of events to be sent at a time). | 

**Required Permissions**

ohos.permission.ACCESS_DDK_HID

**Returns**

Returns **0** if the operation is successful; returns a negative value otherwise.


## Variable Description


### bustype

```
uint16_t Hid_Device::bustype
```
**Description**
Bus type.


### code

```
uint16_t Hid_EmitItem::code
```
**Description**
Event code.


### deviceName

```
const char* Hid_Device::deviceName
```
**Description**
Device name.


### hidAbs

```
struct Hid_AbsAxesArray Hid_EventProperties::hidAbs
```
**Description**
Array of absolute coordinates.


### hidAbsAxes

```
Hid_AbsAxes* Hid_AbsAxesArray::hidAbsAxes
```
**Description**
Absolute coordinates.


### hidAbsFlat

```
int32_t Hid_EventProperties::hidAbsFlat[64]
```
**Description**
Fixed values of the absolute coordinates.


### hidAbsFuzz

```
int32_t Hid_EventProperties::hidAbsFuzz[64]
```
**Description**
Fuzzy values of the absolute coordinates.


### hidAbsMax

```
int32_t Hid_EventProperties::hidAbsMax[64]
```
**Description**
Maximum values of the absolute coordinates.


### hidAbsMin

```
int32_t Hid_EventProperties::hidAbsMin[64]
```
**Description**
Minimum values of the absolute coordinates.


### hidEventType

```
Hid_EventType* Hid_EventTypeArray::hidEventType
```
**Description**
Event type.


### hidEventTypes

```
struct Hid_EventTypeArray Hid_EventProperties::hidEventTypes
```
**Description**
Array of event types.


### hidKeyCode

```
Hid_KeyCode* Hid_KeyCodeArray::hidKeyCode
```
**Description**
Key code.


### hidKeys

```
struct Hid_KeyCodeArray Hid_EventProperties::hidKeys
```
**Description**
Array of key codes.


### hidMiscellaneous

```
struct Hid_MscEventArray Hid_EventProperties::hidMiscellaneous
```
**Description**
Array of miscellaneous events.


### hidMscEvent

```
Hid_MscEvent* Hid_MscEventArray::hidMscEvent
```
**Description**
Miscellaneous event.


### hidRelAxes

```
Hid_RelAxes* Hid_RelAxesArray::hidRelAxes
```
**Description**
Relative coordinates.


### hidRelBits

```
struct Hid_RelAxesArray Hid_EventProperties::hidRelBits
```
**Description**
Array of relative coordinates.


### length [1/5]

```
uint16_t Hid_EventTypeArray::length
```
**Description**
Length of the event type array.


### length [2/5]

```
uint16_t Hid_KeyCodeArray::length
```
**Description**
Length of the key code array.


### length [3/5]

```
uint16_t Hid_AbsAxesArray::length
```
**Description**
Length of the absolute coordinate array.


### length [4/5]

```
uint16_t Hid_RelAxesArray::length
```
**Description**
Length of the relative coordinate array.


### length [5/5]

```
uint16_t Hid_MscEventArray::length
```
**Description**
Length of the miscellaneous event array.


### productId

```
uint16_t Hid_Device::productId
```
**Description**
Product ID.


### properties

```
Hid_DeviceProp* Hid_Device::properties
```
**Description**
Device properties.


### propLength

```
uint16_t Hid_Device::propLength
```
**Description**
Number of device properties.


### type

```
uint16_t Hid_EmitItem::type
```
**Description**
Event type.


### value

```
uint32_t Hid_EmitItem::value
```
**Description**
Event value.


### vendorId

```
uint16_t Hid_Device::vendorId
```
**Description**
Vendor ID.


### version

```
uint16_t Hid_Device::version
```
**Description**
Version number.