harmony 鸿蒙@ohos.usbManager (USB Manager)
@ohos.usbManager (USB Manager)
The usbManager module provides USB device management functions, including USB device list query, bulk data transfer, control transfer, and permission control on the host side as well as USB interface management, and function switch and query on the device side.
NOTE
The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version.
Modules to Import
import { usbManager } from '@kit.BasicServicesKit';
usbManager.getDevices
getDevices(): Array<Readonly<USBDevice>>
Obtains the list of USB devices connected to the host. If no device is connected, an empty list is returned. When the developer mode is disabled, undefined may be returned if no device is connected. Check whether the return value of the API is empty.
System capability: SystemCapability.USB.USBManager
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
801 | Capability not supported. |
Return value
Type | Description |
---|---|
Array<Readonly<USBDevice>> | USB device list. |
Example
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
console.log(`devicesList = ${devicesList}`);
/*
The following is a simple example of the data structure for devicesList:
[
{
name: "1-1",
serial: "",
manufacturerName: "",
productName: "",
version: "",
vendorId: 7531,
productId: 2,
clazz: 9,
subClass: 0,
protocol: 1,
devAddress: 1,
busNum: 1,
configs: [
{
id: 1,
attributes: 224,
isRemoteWakeup: true,
isSelfPowered: true,
maxPower: 0,
name: "1-1",
interfaces: [
{
id: 0,
protocol: 0,
clazz: 9,
subClass: 0,
alternateSetting: 0,
name: "1-1",
endpoints: [
{
address: 129,
attributes: 3,
interval: 12,
maxPacketSize: 4,
direction: 128,
number: 1,
type: 3,
interfaceId: 0,
},
],
},
],
},
],
},
]
*/
usbManager.connectDevice
connectDevice(device: USBDevice): Readonly<USBDevicePipe>
Connects to the USB device based on the device information returned by getDevices(). If the USB service is abnormal, undefined may be returned. Check whether the return value of the API is empty.
- Call usbManager.getDevices to obtain the USB device list.
- Call usbManager.requestRight to request the permission to use the device.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
device | USBDevice | Yes | USB device. The busNum and devAddress parameters obtained by getDevices are used to determine a USB device. Other parameters are passed transparently. |
Return value
Type | Description |
---|---|
Readonly<USBDevicePipe> | USB device pipe for data transfer. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
14400001 | Access right denied. Call requestRight to get the USBDevicePipe access right first. |
Example
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
console.log(`devicepipe = ${devicepipe}`);
usbManager.hasRight
hasRight(deviceName: string): boolean
Checks whether the application has the permission to access the device.
Checks whether the user, for example, the application or system, has the device access permissions. The value true is returned if the user has the device access permissions; the value false is returned otherwise.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceName | string | Yes | Device name, which can be obtained from the device list returned by getDevices. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
Return value
Type | Description |
---|---|
boolean | Returns true if the application has the permission to access the device; returns false otherwise. If this API fails to be called, the following error codes are returned: - 88080385: This API is not initialized. - 88080492: An error occurs when the service data packet is written. - 88080493: An error occurs when the service data packet is read. |
Example
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let right: boolean = usbManager.hasRight(device.name);
console.log(`${right}`);
usbManager.requestRight
requestRight(deviceName: string): Promise<boolean>
Requests the temporary device access permission for the application. This API uses a promise to return the result. System applications are granted the device access permission by default, and you do not need to apply for the permission separately.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceName | string | Yes | Device name, which can be obtained from the device list returned by getDevices. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
Return value
Type | Description |
---|---|
Promise<boolean> | Promise used to return the result. The value true indicates that the temporary device access permissions are granted; and the value false indicates the opposite. If this API fails to be called, the following error codes are returned: - 88080385: This API is not initialized. - 88080392: An error occurs when the API data packet is written. - 88080393: An error occurs when the API data packet is read. - 88080492: An error occurs when the service data packet is written. - 88080493: An error occurs when the service data packet is read. - 88080497: An error occurs when the internal logic of the service is executed. |
Example
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name).then(ret => {
console.log(`requestRight = ${ret}`);
});
usbManager.removeRight
removeRight(deviceName: string): boolean
Removes the device access permission for the application. System applications are granted the device access permission by default, and calling this API will not revoke the permission.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceName | string | Yes | Device name, which can be obtained from the device list returned by getDevices. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
Return value
Type | Description |
---|---|
boolean | Permission removal result. The value true indicates that the access permission is removed successfully; and the value false indicates the opposite. If this API fails to be called, the following error codes are returned: - 88080382: An invalid value or parameter occurs during the API operation. - 88080385: This API is not initialized. - 88080392: An error occurs when the API data packet is written. - 88080393: An error occurs when the API data packet is read. - 88080492: An error occurs when the service data packet is written. - 88080493: An error occurs when the service data packet is read. - 88080497: An error occurs when the internal logic of the service is executed. |
Example
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
let device: usbManager.USBDevice = devicesList[0];
if (usbManager.removeRight(device.name)) {
console.log(`Succeed in removing right`);
}
usbManager.claimInterface
claimInterface(pipe: USBDevicePipe, iface: USBInterface, force ?: boolean): number
Claims a USB interface.
- Call usbManager.getDevices to obtain the USB device list and interfaces.
- Call usbManager.requestRight to request the device access permission.
- Call usbManager.connectDevice to obtain devicepipe as an input parameter.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
pipe | USBDevicePipe | Yes | USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value. |
iface | USBInterface | Yes | USB interface. You can use getDevices to obtain device information and identify the USB interface based on its ID. |
force | boolean | No | Whether to forcibly claim a USB interface. The default value is false, which means not to forcibly claim a USB interface. You can set the value as required. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
Return value
Type | Description |
---|---|
number | Returns 0 if the USB interface is successfully claimed; returns an error code otherwise. The error codes are as follows: - 63: The data exceeds the expected maximum volume. - 88080385: This API is not initialized. - 88080482: An invalid value or parameter occurs during the service. - 88080484: No permission. - 88080492: An error occurs when the service data packet is written. - 88080493: An error occurs when the service data packet is read. - 88080497: An error occurs when the internal logic of the service is executed. - -1: The underlying interface fails to be called. |
Example
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
let interfaces: usbManager.USBInterface = device.configs[0].interfaces[0];
let ret: number= usbManager.claimInterface(devicepipe, interfaces);
console.log(`claimInterface = ${ret}`);
usbManager.releaseInterface
releaseInterface(pipe: USBDevicePipe, iface: USBInterface): number
Releases a USB interface.
Before you do this, ensure that you have claimed the interface by calling usbManager.claimInterface.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
pipe | USBDevicePipe | Yes | USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value. |
iface | USBInterface | Yes | USB interface. You can use getDevices to obtain device information and identify the USB interface based on its ID. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error.Possible causes:1.Mandatory parameters are left unspecified.2.Incorrect parameter types. |
801 | Capability not supported. |
Return value
Type | Description |
---|---|
number | Returns 0 if the USB interface is successfully released; returns an error code otherwise. The error codes are as follows: - 63: The data exceeds the expected maximum volume. - 88080381: Invalid interface operation. - 88080385: This API is not initialized. - 88080482: An invalid value or parameter occurs during the service. - 88080484: No permission. - 88080492: An error occurs when the service data packet is written. - 88080493: An error occurs when the service data packet is read. - 88080497: An error occurs when the internal logic of the service is executed. - -1: The underlying interface fails to be called. |
Example
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
let interfaces: usbManager.USBInterface = device.configs[0].interfaces[0];
let ret: number = usbManager.claimInterface(devicepipe, interfaces);
ret = usbManager.releaseInterface(devicepipe, interfaces);
console.log(`releaseInterface = ${ret}`);
usbManager.setConfiguration
setConfiguration(pipe: USBDevicePipe, config: USBConfiguration): number
Sets the device configuration.
- Call usbManager.getDevices to obtain the USB device list and device configuration.
- Call usbManager.requestRight to request the device access permission.
- Call usbManager.connectDevice to obtain devicepipe as an input parameter.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
pipe | USBDevicePipe | Yes | USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value. |
config | USBConfiguration | Yes | USB configuration. You can use getDevices to obtain device information and identify the USB configuration based on the ID. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
Return value
Type | Description |
---|---|
number | Returns 0 if the USB configuration is successfully set; returns an error code otherwise. The error codes are as follows: - 63: The data exceeds the expected maximum volume. - 88080385: This API is not initialized. - 88080482: An invalid value or parameter occurs during the service. - 88080484: No permission. - 88080492: An error occurs when the service data packet is written. - 88080493: An error occurs when the service data packet is read. - 88080497: An error occurs when the internal logic of the service is executed. - -1: The underlying interface fails to be called. - -17: I/O failure. |
Example
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
let config: usbManager.USBConfiguration = device.configs[0];
let ret: number= usbManager.setConfiguration(devicepipe, config);
console.log(`setConfiguration = ${ret}`);
usbManager.setInterface
setInterface(pipe: USBDevicePipe, iface: USBInterface): number
Sets a USB interface.
- Call usbManager.getDevices to obtain the device list and interfaces.
- Call usbManager.requestRight to request the device access permission.
- Call usbManager.connectDevice to obtain devicepipe as an input parameter.
- Call usbManager.claimInterface to register a communication interface.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
pipe | USBDevicePipe | Yes | USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value. |
iface | USBInterface | Yes | USB interface. You can use getDevices to obtain device information and identify the USB interface based on its id and alternateSetting. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
Return value
Type | Description |
---|---|
number | Returns 0 if the USB interface is successfully set; returns an error code otherwise. The error codes are as follows: - 63: The data exceeds the expected maximum volume. - 88080385: This API is not initialized. - 88080482: An invalid value or parameter occurs during the service. - 88080484: No permission. - 88080492: An error occurs when the service data packet is written. - 88080493: An error occurs when the service data packet is read. - 88080497: An error occurs when the internal logic of the service is executed. - -1: The underlying interface fails to be called. |
Example
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
let interfaces: usbManager.USBInterface = device.configs[0].interfaces[0];
let ret: number = usbManager.claimInterface(devicepipe, interfaces);
ret = usbManager.setInterface(devicepipe, interfaces);
console.log(`setInterface = ${ret}`);
usbManager.getRawDescriptor
getRawDescriptor(pipe: USBDevicePipe): Uint8Array
Obtains the raw USB descriptor. If the USB service is abnormal, undefined may be returned. Check whether the return value of the API is empty.
- Call usbManager.getDevices to obtain the USB device list.
- Call usbManager.requestRight to request the device access permission.
- Call usbManager.connectDevice to obtain devicepipe as an input parameter.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
pipe | USBDevicePipe | Yes | USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
Return value
Type | Description |
---|---|
Uint8Array | Returns the raw USB descriptor if the operation is successful; returns undefined otherwise. |
Example
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
usbManager.requestRight(devicesList[0].name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(devicesList[0]);
let ret: Uint8Array = usbManager.getRawDescriptor(devicepipe);
usbManager.getFileDescriptor
getFileDescriptor(pipe: USBDevicePipe): number
Obtains the file descriptor.
- Call usbManager.getDevices to obtain the USB device list.
- Call usbManager.requestRight to request the device access permission.
- Call usbManager.connectDevice to obtain devicepipe as an input parameter.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
pipe | USBDevicePipe | Yes | USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
Return value
Type | Description |
---|---|
number | Returns the file descriptor corresponding to the device if this API is successful called; returns an error code otherwise. The error codes are as follows: - 63: The data exceeds the expected maximum volume. - 88080385: This API is not initialized. - 88080482: An invalid value or parameter occurs during the service. - 88080484: No permission. - 88080492: An error occurs when the service data packet is written. - 88080493: An error occurs when the service data packet is read. - 88080497: An error occurs when the internal logic of the service is executed. - -1: The underlying interface fails to be called. |
Example
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
usbManager.requestRight(devicesList[0].name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(devicesList[0]);
let ret: number = usbManager.getFileDescriptor(devicepipe);
usbManager.controlTransfer(deprecated)
controlTransfer(pipe: USBDevicePipe, controlparam: USBControlParams, timeout ?: number): Promise<number>
Performs control transfer.
- Call usbManager.getDevices to obtain the USB device list.
- Call usbManager.requestRight to request the device access permission.
- Call usbManager.connectDevice to obtain devicepipe as an input parameter.
NOTE
This API is supported since API version 9 and deprecated since API version 12. You are advised to use usbControlTransfer.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
pipe | USBDevicePipe | Yes | USB device pipe. You need to call connectDevice to obtain its value. |
controlparam | USBControlParams | Yes | Control transfer parameters. Set the parameters as required. For details, see the USB protocol. |
timeout | number | No | (Optional) Timeout duration, in ms. The default value is 0. You can set this parameter as required. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
Return value
Type | Description |
---|---|
Promise<number> | Promise used to return the result, which is the size of the transferred or received data block if the transfer is successful. If the API call fails, the following error codes are returned: - 88080385: This API is not initialized. - 88080482: An invalid value or parameter occurs during the service. - 88080484: No permission. - 88080492: An error occurs when the service data packet is written. - 88080493: An error occurs when the service data packet is read. - 88080497: An error occurs when the internal logic of the service is executed. - -1: The underlying interface fails to be called. |
Example
class PARA {
request: number = 0
reqType: usbManager.USBControlRequestType = 0
target: usbManager.USBRequestTargetType = 0
value: number = 0
index: number = 0
data: Uint8Array = new Uint8Array()
}
let param: PARA = {
request: 0x06,
reqType: 0x80,
target:0,
value: 0x01 << 8|0,
index: 0,
data: new Uint8Array(18)
};
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
usbManager.requestRight(devicesList[0].name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(devicesList[0]);
usbManager.controlTransfer(devicepipe, param).then((ret: number) => {
console.log(`controlTransfer = ${ret}`);
})
usbManager.usbControlTransfer12+
usbControlTransfer(pipe: USBDevicePipe, requestparam: USBDeviceRequestParams, timeout ?: number): Promise<number>
Performs control transfer.
- Call usbManager.getDevices to obtain the USB device list.
- Call usbManager.requestRight to request the device access permission.
- Call usbManager.connectDevice to obtain devicepipe as an input parameter.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
pipe | USBDevicePipe | Yes | USB device pipe, which is used to determine the USB device. |
requestparam | USBDeviceRequestParams | Yes | Control transfer parameters. Set the parameters as required. For details, see the USB protocol. |
timeout | number | No | (Optional) Timeout duration, in ms. The default value is 0, indicating no timeout. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error.Possible causes:1.Mandatory parameters are left unspecified.2.Incorrect parameter types. |
801 | Capability not supported. |
Return value
Type | Description |
---|---|
Promise<number> | Promise used to return the result, which is the size of the transferred or received data block if the transfer is successful. If the API call fails, the following error codes are returned: - 88080385: This API is not initialized. - 88080482: An invalid value or parameter occurs during the service. - 88080484: No permission. - 88080492: An error occurs when the service data packet is written. - 88080493: An error occurs when the service data packet is read. - 88080497: An error occurs when the internal logic of the service is executed. - -1: The underlying interface fails to be called. |
Example
class PARA {
bmRequestType: number = 0
bRequest: number = 0
wValue: number = 0
wIndex: number = 0
wLength: number = 0
data: Uint8Array = new Uint8Array()
}
let param: PARA = {
bmRequestType: 0x80,
bRequest: 0x06,
wValue:0x01 << 8|0,
wIndex: 0,
wLength: 18,
data: new Uint8Array(18)
};
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
usbManager.requestRight(devicesList[0].name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(devicesList[0]);
usbManager.usbControlTransfer(devicepipe, param).then((ret: number) => {
console.log(`usbControlTransfer = ${ret}`);
})
usbManager.bulkTransfer
bulkTransfer(pipe: USBDevicePipe, endpoint: USBEndpoint, buffer: Uint8Array, timeout ?: number): Promise<number>
Performs bulk transfer.
- Call usbManager.getDevices to obtain the USB device list and endpoints.
- Call usbManager.requestRight to request the device access permission.
- Call usbManager.connectDevice to obtain the returned devicepipe.
- Obtain the usbManager.claimInterface API.
- Call the usbManager.bulkTransfer API.
NOTE
The total amount of data (including pipe, endpoint, buffer, and timeout) transferred in bulk must be less than 200 KB.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
pipe | USBDevicePipe | Yes | USB device pipe. You need to call connectDevice to obtain its value. |
endpoint | USBEndpoint | Yes | USB endpoint, which is used to determine the USB interface for data transfer. You need to call getDevices to obtain the device information list and endpoint. Wherein, address is used to determine the endpoint address, direction is used to determine the endpoint direction, and interfaceId is used to determine the USB interface to which the endpoint belongs. Other parameters are passed transparently. |
buffer | Uint8Array | Yes | Buffer used to write or read data. |
timeout | number | No | (Optional) Timeout duration, in ms. The default value is 0. You can set this parameter as required. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
Return value
Type | Description |
---|---|
Promise<number> | Promise used to return the result, which is the size of the transferred or received data block if the transfer is successful. If the API call fails, the following error codes are returned: - 63: The data exceeds the expected maximum volume. - 88080385: This API is not initialized. - 88080482: An invalid value or parameter occurs during the service. - 88080484: No permission. - 88080492: An error occurs when the service data packet is written. - 88080493: An error occurs when the service data packet is read. - 88080497: An error occurs when the internal logic of the service is executed. - -1: The underlying interface fails to be called. - -3: The parameter is invalid. - -202: The device is not found. |
Example
NOTE
The following sample code is only a basic process for calling the bulkTransfer API. In actual calling, you must comply with the device-related protocols to ensure correct data transfer and device compatibility.
// Call usbManager.getDevices to obtain a data set. Then, obtain a USB device and its access permission.
// Pass the obtained USB device as a parameter to usbManager.connectDevice. Then, call usbManager.connectDevice to connect the USB device.
// Call usbManager.claimInterface to claim a USB interface. After that, call usbManager.bulkTransfer to start bulk transfer.
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
for (let i = 0; i < device.configs[0].interfaces.length; i++) {
if (device.configs[0].interfaces[i].endpoints[0].attributes == 2) {
let endpoint: usbManager.USBEndpoint = device.configs[0].interfaces[i].endpoints[0];
let interfaces: usbManager.USBInterface = device.configs[0].interfaces[i];
let ret: number = usbManager.claimInterface(devicepipe, interfaces);
let buffer = new Uint8Array(128);
usbManager.bulkTransfer(devicepipe, endpoint, buffer).then((ret: number) => {
console.log(`bulkTransfer = ${ret}`);
});
}
}
usbManager.usbSubmitTransfer18+
usbSubmitTransfer(transfer: UsbDataTransferParams): void
Requests a USB data transfer.
This API uses an asynchronous callback to return the result.
- Call usbManager.getDevices to obtain the USB device list and endpoints.
- Call usbManager.requestRight to request the device access permission.
- Call usbManager.connectDevice to obtain the returned devicepipe.
- Obtain the usbManager.claimInterface API.
- Call the usbManager.usbSubmitTransfer API.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
transfer | UsbDataTransferParams | Yes | As a USB data transfer interface, it is required for a client to initiate a transfer request. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types. |
801 | Capability not supported. |
14400001 | Access right denied. Call requestRight to get the USBDevicePipe access right first. |
14400007 | Resource busy. |
14400008 | No such device (it may have been disconnected). |
14400009 | Insufficient memory. |
14400012 | Transmission I/O error. |
Example
NOTE
The following sample code shows the basic process for calling the usbSubmitTransfer API and it needs to be executed in a specific method. In actual calling, you must comply with the device-related protocols to ensure correct data transfer and device compatibility.
// Call usbManager.getDevices to obtain a data set. Then, obtain a USB device and its access permission.
// Pass the obtained USB device as a parameter to usbManager.connectDevice. Then, call usbManager.connectDevice to connect the USB device.
// Call usbManager.claimInterface to claim a USB interface. After that, call usbManager.bulkTransfer to start bulk transfer.
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
return;
}
let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
// Obtain the endpoint address.
let endpoint = device.configs[0].interfaces[0]?.endpoints.find((value) => {
return value.direction === 0 && value.type === 2
})
// Obtain the first ID of the device.
let ret: number = usbManager.claimInterface(devicepipe, device.configs[0].interfaces[0], true);
let transferParams: usbManager.UsbDataTransferParams = {
devPipe: devicepipe,
flags: usbManager.UsbTransferFlags.USB_TRANSFER_SHORT_NOT_OK,
endpoint: 1,
type: usbManager.UsbEndpointTransferType.TRANSFER_TYPE_BULK,
timeout: 2000,
length: 10,
callback: () => {},
userData: new Uint8Array(10),
buffer: new Uint8Array(10),
isoPacketCount: 0,
};
try {
transferParams.endpoint=endpoint?.address as number;
transferParams.callback=(err, callBackData: usbManager.SubmitTransferCallback)=>{
console.info('callBackData =' +JSON.stringify(callBackData));
}
usbManager.usbSubmitTransfer(transferParams);
console.info('USB transfer request submitted.');
} catch (error) {
console.error('USB transfer failed:', error);
}
usbManager.usbCancelTransfer18+
usbCancelTransfer(transfer: UsbDataTransferParams): void
Cancels an asynchronous USB data transfer request.
- Call usbManager.getDevices to obtain the USB device list and endpoints.
- Call usbManager.requestRight to request the device access permission.
- Call usbManager.connectDevice to obtain the returned devicepipe.
- Obtain the usbManager.claimInterface API.
- Call the usbManager.usbCancelTransfer API.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
transfer | UsbDataTransferParams | Yes | Only USBDevicePipe and endpoint are required for canceling the transfer. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types. |
801 | Capability not supported. |
14400001 | Access right denied. Call requestRight to get the USBDevicePipe access right first. |
14400008 | No such device (it may have been disconnected). |
14400010 | Other USB error. Possible causes: 1.Unrecognized discard error code. |
14400011 | The transfer is not in progress, or is already complete or cancelled. |
Return value
Type | Description |
---|---|
<void> | None. |
Example
NOTE
The following sample code shows the basic process for calling the usbCancelTransfer API and it needs to be executed in a specific method. In actual calling, you must comply with the device-related protocols to ensure correct data transfer and device compatibility.
// Call usbManager.getDevices to obtain a data set. Then, obtain a USB device and its access permission.
// Pass the obtained USB device as a parameter to usbManager.connectDevice. Then, call usbManager.connectDevice to connect the USB device.
// Call usbManager.claimInterface to claim a USB interface. After that, call usbManager.bulkTransfer to start bulk transfer.
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
return;
}
let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
// Obtain the endpoint address.
let endpoint = device.configs[0].interfaces[0]?.endpoints.find((value) => {
return value.direction === 0 && value.type === 2
})
// Obtain the first ID of the device.
let ret: number = usbManager.claimInterface(devicepipe, device.configs[0].interfaces[0], true);
let transferParams: usbManager.UsbDataTransferParams = {
devPipe: devicepipe,
flags: usbManager.UsbTransferFlags.USB_TRANSFER_SHORT_NOT_OK,
endpoint: 1,
type: usbManager.UsbEndpointTransferType.TRANSFER_TYPE_BULK,
timeout: 2000,
length: 10,
callback: () => {},
userData: new Uint8Array(10),
buffer: new Uint8Array(10),
isoPacketCount: 0,
};
try {
transferParams.endpoint=endpoint?.address as number;
transferParams.callback=(err, callBackData: usbManager.SubmitTransferCallback)=>{
console.info('callBackData =' +JSON.stringify(callBackData));
}
usbManager.usbSubmitTransfer(transferParams);
usbManager.usbCancelTransfer(transferParams);
console.info('USB transfer request submitted.');
} catch (error) {
console.error('USB transfer failed:', error);
}
usbManager.closePipe
closePipe(pipe: USBDevicePipe): number
Closes a USB device pipe.
- Call usbManager.getDevices to obtain the USB device list.
- Call usbManager.requestRight to request the device access permission.
- Call usbManager.connectDevice to obtain devicepipe as an input parameter.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
pipe | USBDevicePipe | Yes | USB device pipe, which is used to determine the message control channel. You need to call connectDevice to obtain its value. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
Return value
Type | Description |
---|---|
number | Returns 0 if the USB device pipe is closed successfully; returns an error code otherwise. The error codes are as follows: - 63: The data exceeds the expected maximum volume. - 88080393: An error occurs when the API data packet is read. - 88080482: An invalid value or parameter occurs during the service. - 88080484: No permission. - 88080493: An error occurs when the service data packet is read. - 88080497: An error occurs when the internal logic of the service is executed. - -1: The underlying interface fails to be called. |
Example
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
console.log(`device list is empty`);
}
usbManager.requestRight(devicesList[0].name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(devicesList[0]);
let ret: number = usbManager.closePipe(devicepipe);
console.log(`closePipe = ${ret}`);
usbManager.hasAccessoryRight14+
hasAccessoryRight(accessory: USBAccessory): boolean
Checks whether the application has the permission to access the USB accessory.
You need to call usbManager.getAccessoryList to obtain the accessory list and use USBAccessory as a parameter.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
accessory | USBAccessory | Yes | USB accessory. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
14400004 | Service exception. Possible causes: 1. No accessory is plugged in. |
14400005 | Database operation exception. |
14401001 | The target USBAccessory not matched. |
Return value
Type | Description |
---|---|
boolean | The value true indicates that the application has the permission to access the USB accessory; false indicates the opposite. |
Example
import { hilog } from '@kit.PerformanceAnalysisKit';
try {
let accList: usbManager.USBAccessory[] = usbManager.getAccessoryList()
let flag = usbManager.hasAccessoryRight(accList[0])
hilog.info(0, 'testTag ui', `hasAccessoryRight success, ret:${flag}`)
} catch (error) {
hilog.info(0, 'testTag ui', `hasAccessoryRight error ${error.code}, message is ${error.message}`)
}
usbManager.requestAccessoryRight14+
requestAccessoryRight(accessory: USBAccessory): Promise<boolean>
Requests the permission to access a USB accessory for a specified application.
You need to call usbManager.getAccessoryList to obtain the accessory list and use USBAccessory as a parameter.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
accessory | USBAccessory | Yes | USB accessory. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
14400004 | Service exception. Possible causes: 1. No accessory is plugged in. |
14400005 | Database operation exception. |
14401001 | The target USBAccessory not matched. |
Return value
Type | Description |
---|---|
Promise<boolean> | Promise used to return the application result. The value true indicates that the device access permissions are granted; false indicates the opposite. |
Example
import { hilog } from '@kit.PerformanceAnalysisKit';
try {
let accList: usbManager.USBAccessory[] = usbManager.getAccessoryList()
let flag = usbManager.requestAccessoryRight(accList[0])
hilog.info(0, 'testTag ui', `requestAccessoryRight success, ret:${flag}`)
} catch (error) {
hilog.info(0, 'testTag ui', `requestAccessoryRight error ${error.code}, message is ${error.message}`)
}
usbManager.cancelAccessoryRight14+
cancelAccessoryRight(accessory: USBAccessory): void
Cancels the permission of the current application to access USB accessories.
You need to call usbManager.getAccessoryList to obtain the accessory list and use USBAccessory as a parameter.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
accessory | USBAccessory | Yes | USB accessory. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
14400004 | Service exception. Possible causes: 1. No accessory is plugged in. |
14400005 | Database operation exception. |
14401001 | The target USBAccessory not matched. |
Example
import { hilog } from '@kit.PerformanceAnalysisKit';
try {
let accList: usbManager.USBAccessory[] = usbManager.getAccessoryList()
let flag = usbManager.requestAccessoryRight(accList[0])
usbManager.cancelAccessoryRight(accList[0])
hilog.info(0, 'testTag ui', `cancelAccessoryRight success`)
} catch (error) {
hilog.info(0, 'testTag ui', `cancelAccessoryRight error ${error.code}, message is ${error.message}`)
}
usbManager.getAccessoryList14+
getAccessoryList(): Array
Obtains the list of USB accessories connected to the host.
System capability: SystemCapability.USB.USBManager
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
801 | Capability not supported. |
14400004 | Service exception. Possible causes: 1. No accessory is plugged in. |
Return value
Type | Description |
---|---|
Array |
List of USB accessories (read-only). Currently, only one USB accessory is contained in the list. |
Example
import { hilog } from '@kit.PerformanceAnalysisKit';
try {
let accList: usbManager.USBAccessory[] = usbManager.getAccessoryList()
hilog.info(0, 'testTag ui', `getAccessoryList success, accList: ${JSON.stringify(accList)}`)
} catch (error) {
hilog.info(0, 'testTag ui', `getAccessoryList error ${error.code}, message is ${error.message}`)
}
usbManager.openAccessory14+
openAccessory(accessory: USBAccessory): USBAccessoryHandle
Obtains the accessory handle and opens the accessory file descriptor.
You need to call usbManager.getAccessoryList to obtain the accessory list and use USBAccessory as a parameter.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
accessory | USBAccessory | Yes | USB accessory. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
14400001 | Permission denied. Call requestAccessoryRight to get the right first. |
14400004 | Service exception. Possible causes: 1. No accessory is plugged in. |
14401001 | The target USBAccessory not matched. |
14401002 | Failed to open the native accessory node. |
14401003 | Cannot reopen the accessory. |
Return value
Type | Description |
---|---|
USBAccessoryHandle | USB accessory handle. |
Example
import { hilog } from '@kit.PerformanceAnalysisKit';
try {
let accList: usbManager.USBAccessory[] = usbManager.getAccessoryList()
let flag = usbManager.requestAccessoryRight(accList[0])
let handle = usbManager.openAccessory(accList[0])
hilog.info(0, 'testTag ui', `openAccessory success`)
} catch (error) {
hilog.info(0, 'testTag ui', `openAccessory error ${error.code}, message is ${error.message}`)
}
usbManager.closeAccessory14+
closeAccessory(accessoryHandle: USBAccessoryHandle): void
Closes the accessory file descriptor.
You need to call usbManager.openAccessory to obtain the accessory list and use USBAccessoryHandle as a parameter.
System capability: SystemCapability.USB.USBManager
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
accessoryHandle | USBAccessoryHandle | Yes | USB accessory handle, obtained through openAccessory. |
Error codes
For details about the error codes, see USB Service Error Codes.
ID | Error Message |
---|---|
401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. |
801 | Capability not supported. |
14400004 | Service exception. Possible causes: 1. No accessory is plugged in. |
Example
import { hilog } from '@kit.PerformanceAnalysisKit';
try {
let accList: usbManager.USBAccessory[] = usbManager.getAccessoryList()
let flag = usbManager.requestAccessoryRight(accList[0])
let handle = usbManager.openAccessory(accList[0])
usbManager.closeAccessory(handle)
hilog.info(0, 'testTag ui', `closeAccessory success`)
} catch (error) {
hilog.info(0, 'testTag ui', `closeAccessory error ${error.code}, message is ${error.message}`)
}
USBEndpoint
Represents the USB endpoint from which data is sent or received. You can obtain the USB endpoint through USBInterface.
System capability: SystemCapability.USB.USBManager
Name | Type | Mandatory | Description |
---|---|---|---|
address | number | Yes | Endpoint address. |
attributes | number | Yes | Endpoint attributes. |
interval | number | Yes | Endpoint interval. |
maxPacketSize | number | Yes | Maximum size of data packets on the endpoint. |
direction | USBRequestDirection | Yes | Endpoint direction. |
number | number | Yes | Endpoint number. |
type | number | Yes | Endpoint type. |
interfaceId | number | Yes | Unique ID of the interface to which the endpoint belongs. |
USBInterface
Represents a USB interface. One USBConfiguration object can contain multiple USBInterface instances, each providing a specific function.
System capability: SystemCapability.USB.USBManager
Name | Type | Mandatory | Description |
---|---|---|---|
id | number | Yes | Unique ID of the USB interface. |
protocol | number | Yes | Interface protocol. |
clazz | number | Yes | Device type. |
subClass | number | Yes | Device subclass. |
alternateSetting | number | Yes | Settings for alternating between descriptors of the same USB interface. |
name | string | Yes | Interface name. |
endpoints | Array<USBEndpoint> | Yes | Endpoints that belong to the USB interface. |
USBConfiguration
Represents the USB configuration. One USBDevice can contain multiple USBConfig instances.
System capability: SystemCapability.USB.USBManager
Name | Type | Mandatory | Description |
---|---|---|---|
id | number | Yes | Unique ID of the USB configuration. |
attributes | number | Yes | Configuration attributes. |
maxPower | number | Yes | Maximum power consumption, in mA. |
name | string | Yes | Configuration name, which can be left empty. |
isRemoteWakeup | boolean | Yes | Support for remote wakeup. |
isSelfPowered | boolean | Yes | Support for independent power supplies. |
interfaces | Array <USBInterface> | Yes | Supported interface attributes. |
USBDevice
Represents the USB device information.
System capability: SystemCapability.USB.USBManager
Name | Type | Mandatory | Description |
---|---|---|---|
busNum | number | Yes | Bus address. |
devAddress | number | Yes | Device address. |
serial | string | Yes | Sequence number. |
name | string | Yes | Device name. |
manufacturerName | string | Yes | Device manufacturer. |
productName | string | Yes | Product name. |
version | string | Yes | Version number. |
vendorId | number | Yes | Vendor ID. |
productId | number | Yes | Product ID. |
clazz | number | Yes | Device class. |
subClass | number | Yes | Device subclass. |
protocol | number | Yes | Device protocol code. |
configs | Array<USBConfiguration> | Yes | Device configuration descriptor information. |
USBDevicePipe
Represents a USB device pipe, which is used to determine a USB device.
System capability: SystemCapability.USB.USBManager
Name | Type | Mandatory | Description |
---|---|---|---|
busNum | number | Yes | Bus address. |
devAddress | number | Yes | Device address. |
USBControlParams(deprecated)
Represents control transfer parameters.
NOTE
This API is supported since API version 9 and deprecated since API version 18. You are advised to use USBDeviceRequestParams instead.
System capability: SystemCapability.USB.USBManager
Name | Type | Mandatory | Description |
---|---|---|---|
request | number | Yes | Request type. |
target | USBRequestTargetType | Yes | Request target type. |
reqType | USBControlRequestType | Yes | Control request type. |
value | number | Yes | Request parameter. |
index | number | Yes | Index of the request parameter. |
data | Uint8Array | Yes | Buffer for writing or reading data. |
USBDeviceRequestParams12+
Represents control transfer parameters.
System capability: SystemCapability.USB.USBManager
Name | Type | Mandatory | Description |
---|---|---|---|
bmRequestType | number | Yes | Control request type. |
bRequest | number | Yes | Request type. |
wValue | number | Yes | Request parameter. |
wIndex | number | Yes | Index of the request parameter. |
wLength | number | Yes | Length of the requested data. |
data | Uint8Array | Yes | Buffer for writing or reading data. |
USBRequestTargetType
Enumerates request target types.
System capability: SystemCapability.USB.USBManager
Name | Value | Description |
---|---|---|
USB_REQUEST_TARGET_DEVICE | 0 | Device. |
USB_REQUEST_TARGET_INTERFACE | 1 | Interface. |
USB_REQUEST_TARGET_ENDPOINT | 2 | Endpoint. |
USB_REQUEST_TARGET_OTHER | 3 | Other. |
USBControlRequestType
Enumerates control request types.
System capability: SystemCapability.USB.USBManager
Name | Value | Description |
---|---|---|
USB_REQUEST_TYPE_STANDARD | 0 | Standard. |
USB_REQUEST_TYPE_CLASS | 1 | Class. |
USB_REQUEST_TYPE_VENDOR | 2 | Vendor. |
USBRequestDirection
Enumerates request directions.
System capability: SystemCapability.USB.USBManager
Name | Value | Description |
---|---|---|
USB_REQUEST_DIR_TO_DEVICE | 0 | Request for writing data from the host to the device. |
USB_REQUEST_DIR_FROM_DEVICE | 0x80 | Request for reading data from the device to the host. |
USBAccessory14+
Describes the USB accessory information.
System capability: SystemCapability.USB.USBManager
Name | Type | Mandatory | Description |
---|---|---|---|
manufacturer | string | Yes | Manufacturer of an accessory. |
product | string | Yes | Product type of an accessory. |
description | string | Yes | Description of an accessory. |
version | string | Yes | Version of an accessory. |
serialNumber | string | Yes | SN of an accessory. |
USBAccessoryHandle14+
Describes the USB accessory handle.
System capability: SystemCapability.USB.USBManager
Name | Type | Mandatory | Description |
---|---|---|---|
accessoryFd | number | Yes | Accessory file descriptor. A valid accessoryFd is a positive integer. |
UsbDataTransferParams18+
As a USB data transfer interface, it is required for a client to initiate a transfer request.
System capability: SystemCapability.USB.USBManager
Name | Type | Mandatory | Description |
---|---|---|---|
devPipe | USBDevicePipe | Yes | USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value. |
flags | UsbTransferFlags | Yes | USB transfer flag. |
endpoint | number | Yes | Endpoint address, which is a positive integer. |
type | UsbEndpointTransferType | Yes | Transfer type. |
timeout | number | Yes | Timeout duration, in ms. |
length | number | Yes | Length of the data buffer, in bytes. The value must be a non-negative number (expected length). |
callback | AsyncCallback<SubmitTransferCallback> | Yes | Information returned by the callback. |
userData | Uint8Array | Yes | User data. |
buffer | Uint8Array | Yes | Buffer, which is used to store data for read or write requests. |
isoPacketCount | number | Yes | Number of data packets during real-time transfer, used only for I/Os with real-time transfer endpoints. The value must be a non-negative number. |
UsbTransferFlags18+
Enumerates USB transfer flags.
System capability: SystemCapability.USB.USBManager
Name | Value | Description |
---|---|---|
USB_TRANSFER_SHORT_NOT_OK | 0 | Reports short frames as errors. |
USB_TRANSFER_FREE_BUFFER | 1 | Automatically releases the transfer buffer. |
USB_TRANSFER_FREE_TRANSFER | 2 | Automatically transfers after the callback is complete. |
USB_TRANSFER_ADD_ZERO_PACKET | 3 | Adds an additional data packet to the transfer. |
UsbEndpointTransferType18+
Enumerates USB transfer types.
System capability: SystemCapability.USB.USBManager
Name | Value | Description |
---|---|---|
TRANSFER_TYPE_ISOCHRONOUS | 0x1 | Real-time transfer. |
TRANSFER_TYPE_BULK | 0x2 | Performs bulk transfer. |
TRANSFER_TYPE_INTERRUPT | 0x3 | Interrupt transfer. |
SubmitTransferCallback18+
Transfers USB data packets in an asynchronous manner.
System capability: SystemCapability.USB.USBManager
Name | Type | Mandatory | Description |
---|---|---|---|
actualLength | number | Yes | Actual length of the read or written data, in bytes. |
status | UsbTransferStatus | Yes | Status after reading or writing is complete. |
isoPacketDescs | Array |
Yes | Packet information transferred in real time. |
UsbTransferStatus18+
Enumerates the statuses returned by libusb through callback after the actual processing is complete.
System capability: SystemCapability.USB.USBManager
Name | Value | Description |
---|---|---|
TRANSFER_COMPLETED | 0 | Transfer completed. |
TRANSFER_ERROR | 1 | Transfer failed. |
TRANSFER_TIMED_OUT | 2 | Transfer timeout. |
TRANSFER_CANCELED | 3 | Transfer canceled. |
TRANSFER_STALL | 4 | Transfer stalled (at bulk/interrupt endpoint). |
TRANSFER_NO_DEVICE | 5 | Device disconnected. |
TRANSFER_OVERFLOW | 6 | Data overflow. |
UsbIsoPacketDescriptor18+
Describes packet information returned in real time by the transfer callback.
System capability: SystemCapability.USB.USBManager
Name | Type | Mandatory | Description |
---|---|---|---|
length | number | Yes | Expected length of the read or written data, in bytes. |
actualLength | number | Yes | Actual length of the read or written data, in bytes. |
status | UsbTransferStatus | Yes | Status returned by callback. |
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