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Overview of developing Windows applications for USB devices

  • Artikkeli

Summary:

  • Guidelines for choosing the right programming model
  • UWP app and desktop app developer experience

Important APIs:

This article provides guidelines for deciding whether you should write a UWP app or a Windows desktop app to communicate with a USB device.

Windows provides API sets that you can use to write apps that talk to custom USB devices. The API performs common USB-related tasks such as, finding the device, data transfers.

Custom device in this context means, a device for which Microsoft doesn't provide an in-box class driver. Instead, you can install WinUSB (Winusb.sys) as the device driver.

Choosing a programming model

If you install Winusb.sys, here are the programming model options:

The strategy for choosing the best programming model depends on various factors.

  • Will your app communicate with an internal USB device?

    The APIs are primarily designed for accessing peripheral devices. The API can also access PC internal USB devices. However access to PC internal USB devices from a UWP app is limited to a privileged app that is explicitly declared in device metadata by the OEM for that PC.

  • Will your app communicate with USB isochronous endpoints?

    If your app transmits data to or from isochronous endpoints of the device, you must write a Windows desktop app. In Windows 8.1, new WinUSB Functions have been added to the API set that allows a desktop app to send data to and receive data from isochronous endpoints.

  • Is your app a "control panel" type of app?

    UWP apps are per-user apps and don't have the ability to make changes outside the scope of each app. For these types of apps, you must write a Windows desktop app.

  • Is the USB device class supported classes by UWP apps?

    Write a UWP app if your device belongs to one these device classes.

    • name:cdcControl, classId:02 * *
    • name:physical, classId:05 * *
    • name:personalHealthcare, classId:0f 00 00
    • name:activeSync, classId:ef 01 01
    • name:palmSync, classId:ef 01 02
    • name:deviceFirmwareUpdate, classId:fe 01 01
    • name:irda, classId:fe 02 00
    • name:measurement, classId:fe 03 *
    • name:vendorSpecific, classId:ff * *

    Note

    If your device belongs to DeviceFirmwareUpdate class, your app must be a privileged app.

If your device doesn't belong to one the preceding device classes, write a Windows desktop app.

Driver requirement

Driver requirement UWP app Windows desktop app
Function driver Microsoft-provided Winusb.sys (kernel-mode driver). Microsoft-provided Winusb.sys (kernel-mode driver).
Filter driver If filter drivers are present, access is limited to privileged apps. The app is declared as privileged apps in device metadata by the OEM. Filter driver can be present in the kernel mode device stack as long as it doesn't block access to Winusb.sys.

Code samples

Sample UWP app Windows desktop app
Get started with these samples

Development tools

Development tools UWP app Windows desktop app
Developer environment Microsoft Visual Studio 2013

Microsoft Windows Software Development Kit (SDK) for Windows 8.1		 Use WinUSB Application template included with Visual Studio (Ultimate or Professional) and Windows Driver Kit (WDK) 8 or later.

For isochronous transfers, Visual Studio 2013 with Windows Driver Kit (WDK) 8.1 or later.
Programming languages C#, VB.NET, C++, JavaScript C/C++

Feature implementation

Key scenario UWP app Windows desktop app
Device discovery Use Windows.Devices.Enumeration namespace to get a UsbDevice. Use SetupAPI and WinUsb_Initialize to get a WINUSB_INTERFACE_HANDLE.
USB control transfer UsbSetupPacket
UsbControlRequestType
UsbDevice.SendControlInTransferAsync
UsbDevice.SendControlOutTransferAsync		 WINUSB_SETUP_PACKET
WinUsb_ControlTransfer
Getting USB descriptors UsbDevice.DeviceDescriptor
UsbConfiguration.Descriptors
UsbInterface.Descriptors
UsbEndpointDescriptor		 WinUsb_GetDescriptor
Sending USB bulk transfer UsbBulkInPipe
UsbBulkOutPipe		 WinUsb_ReadPipe
WinUsb_WritePipe
Sending USB interrupt transfer UsbInterruptInPipe
UsbInterruptOutPipe		 WinUsb_ReadPipe
WinUsb_WritePipe
Sending USB isochronous transfer Not supported. WinUsb_ReadIsochPipe
WinUsb_ReadIsochPipeAsap
WinUsb_WriteIsochPipe
WinUsb_WriteIsochPipeAsap
Closing the device UsbDevice.Close WinUsb_Free

Documentation

Documentation UWP app Windows desktop app
Programming guide Talking to USB devices, start to finish How to Access a USB Device by Using WinUSB Functions
API reference Windows.Devices.Usb WinUSB Functions