Component | Build Status | NuGet Package |
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System.Device.UsbStream |
UsbStream
class provides a seamless interface to a stream that can read from and write to an USB Device that's enumerated as a WinUSB device.
This allows shipping your .NET nanoFramework device as an USB device without the need for any INF file or specific driver instalation.
Creating an UsbStream
requries 2 parameters: a Guid
that will be used as the Device Interface ID and a string
which will be used as the device description for the USB device.
private static Guid deviceInterfaceId = new Guid("9e48651c-fa68-4b39-8731-1ee84659aac5");
private static string deviceDescription = "nanoDevice";
// create USB Stream
var usbStream = UsbClient.CreateUsbStream(deviceInterfaceId, deviceDescription);
To write to the UsbStream
just call the Write()
method just like any other .NET stream. Like this:
// buffer with dummy data
var bufer = new byte[] { 1, 2, 3 };
usbStream.Write(bufer, 0, bufer.Length);
USB can be hard. Be prepared for that! There are a number of issues that are prone to cause frustration. Follows some (hopefully valuable) advice.
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If you need to debug device enumeration issues and check what's being passed from the devices, install a tool such as USB Device Tree Viewer from Uwe Sieber. With it you can peruse into every bit of detail about USB device, their interfaces, end points, strings, etc.
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Another great tool is USBDeview from NirSoft. This tool lists all USB devices that currently connected to your computer, as well as all USB devices that you previously used. Extended information is displayed for each USB device. It's possible to uninstall/disable and enable USB devices from the tool.
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Windows caches enumeration of USB devices. What's the problem with that? During development, if the enumeration fails at some point, the device most likely will be marked as being enumerated and on the next connection Windows won't do it again. This can cause the enumeration data to be wrong or incomplete. To fix this and truly force the enumeration to happen from scratch, make sure that:
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Delete the device from the Device Manager.
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Delete the entry from the enumeration cache in Registry. This lives at
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\usbflags\vvvvpppprrrr
Where
vvvv
is the vendor id,pppp
is the PID andrrrr
is the device release number.
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For documentation, providing feedback, issues and finding out how to contribute please refer to the Home repo.
Join our Discord community here.
The list of contributors to this project can be found at CONTRIBUTORS.
The nanoFramework Class Libraries are licensed under the MIT license.
This project has adopted the code of conduct defined by the Contributor Covenant to clarify expected behaviour in our community. For more information see the .NET Foundation Code of Conduct.
This project is supported by the .NET Foundation.