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Opens a USB device by vendor and product id.
Sets DataReceivedEnabled=True.
Hooks DataReceived event.
Writes all command line text to Ep01
Dumps received data to the console window.
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using System; using System.Text; using System.Text.RegularExpressions; using LibUsbDotNet; using LibUsbDotNet.Main; namespace Examples { internal class ReadWriteEventDriven { public static DateTime LastDataEventDate = DateTime.Now; public static UsbDevice MyUsbDevice; #region SET YOUR USB Vendor and Product ID! public static UsbDeviceFinder MyUsbFinder = new UsbDeviceFinder(1234, 1); #endregion public static void Main(string[] args) { ErrorCode ec = ErrorCode.None; try { // Find and open the usb device. MyUsbDevice = UsbDevice.OpenUsbDevice(MyUsbFinder); // If the device is open and ready if (MyUsbDevice == null) throw new Exception("Device Not Found."); // If this is a "whole" usb device (libusb-win32, linux libusb-1.0) // it exposes an IUsbDevice interface. If not (WinUSB) the // 'wholeUsbDevice' variable will be null indicating this is // an interface of a device; it does not require or support // configuration and interface selection. IUsbDevice wholeUsbDevice = MyUsbDevice as IUsbDevice; if (!ReferenceEquals(wholeUsbDevice, null)) { // This is a "whole" USB device. Before it can be used, // the desired configuration and interface must be selected. // Select config #1 wholeUsbDevice.SetConfiguration(1); // Claim interface #0. wholeUsbDevice.ClaimInterface(0); } // open read endpoint 1. UsbEndpointReader reader = MyUsbDevice.OpenEndpointReader(ReadEndpointID.Ep01); // open write endpoint 1. UsbEndpointWriter writer = MyUsbDevice.OpenEndpointWriter(WriteEndpointID.Ep01); // Remove the exepath/startup filename text from the begining of the CommandLine. string cmdLine = Regex.Replace( Environment.CommandLine, "^\".+?\"^.*? |^.*? ", "", RegexOptions.Singleline); if (!String.IsNullOrEmpty(cmdLine)) { reader.DataReceived += (OnRxEndPointData); reader.DataReceivedEnabled = true; int bytesWritten; ec = writer.Write(Encoding.Default.GetBytes(cmdLine), 2000, out bytesWritten); if (ec != ErrorCode.None) throw new Exception(UsbDevice.LastErrorString); LastDataEventDate = DateTime.Now; while ((DateTime.Now - LastDataEventDate).TotalMilliseconds < 100) { } // Always disable and unhook event when done. reader.DataReceivedEnabled = false; reader.DataReceived -= (OnRxEndPointData); Console.WriteLine("\r\nDone!\r\n"); } else throw new Exception("Nothing to do."); } catch (Exception ex) { Console.WriteLine(); Console.WriteLine((ec != ErrorCode.None ? ec + ":" : String.Empty) + ex.Message); } finally { if (MyUsbDevice != null) { if (MyUsbDevice.IsOpen) { // If this is a "whole" usb device (libusb-win32, linux libusb-1.0) // it exposes an IUsbDevice interface. If not (WinUSB) the // 'wholeUsbDevice' variable will be null indicating this is // an interface of a device; it does not require or support // configuration and interface selection. IUsbDevice wholeUsbDevice = MyUsbDevice as IUsbDevice; if (!ReferenceEquals(wholeUsbDevice, null)) { // Release interface #0. wholeUsbDevice.ReleaseInterface(0); } MyUsbDevice.Close(); } } MyUsbDevice = null; // Free usb resources UsbDevice.Exit(); // Wait for user input.. Console.ReadKey(); } } private static void OnRxEndPointData(object sender, EndpointDataEventArgs e) { LastDataEventDate = DateTime.Now; Console.Write(Encoding.Default.GetString(e.Buffer, 0, e.Count)); } } }
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Imports System Imports System.Text Imports System.Text.RegularExpressions Imports LibUsbDotNet Imports LibUsbDotNet.Main Namespace Examples Friend Class ReadWriteEventDriven Public Shared LastDataEventDate As DateTime = DateTime.Now Public Shared MyUsbDevice As UsbDevice #Region "SET YOUR USB Vendor and Product ID!" Public Shared MyUsbFinder As New UsbDeviceFinder(1234, 1) #End Region Public Shared Sub Main(args As String()) Dim ec As ErrorCode = ErrorCode.None Try ' Find and open the usb device. MyUsbDevice = UsbDevice.OpenUsbDevice(MyUsbFinder) ' If the device is open and ready If MyUsbDevice Is Nothing Then Throw New Exception("Device Not Found.") End If ' If this is a "whole" usb device (libusb-win32, linux libusb-1.0) ' it exposes an IUsbDevice interface. If not (WinUSB) the ' 'wholeUsbDevice' variable will be null indicating this is ' an interface of a device; it does not require or support ' configuration and interface selection. Dim wholeUsbDevice As IUsbDevice = TryCast(MyUsbDevice, IUsbDevice) If Not ReferenceEquals(wholeUsbDevice, Nothing) Then ' This is a "whole" USB device. Before it can be used, ' the desired configuration and interface must be selected. ' Select config #1 wholeUsbDevice.SetConfiguration(1) ' Claim interface #0. wholeUsbDevice.ClaimInterface(0) End If ' open read endpoint 1. Dim reader As UsbEndpointReader = MyUsbDevice.OpenEndpointReader(ReadEndpointID.Ep01) ' open write endpoint 1. Dim writer As UsbEndpointWriter = MyUsbDevice.OpenEndpointWriter(WriteEndpointID.Ep01) ' Remove the exepath/startup filename text from the begining of the CommandLine. Dim cmdLine As String = Regex.Replace(Environment.CommandLine, "^"".+?""^.*? |^.*? ", "", RegexOptions.Singleline) If Not [String].IsNullOrEmpty(cmdLine) Then reader.DataReceived += (AddressOf OnRxEndPointData) reader.DataReceivedEnabled = True Dim bytesWritten As Integer ec = writer.Write(Encoding.[Default].GetBytes(cmdLine), 2000, bytesWritten) If ec <> ErrorCode.None Then Throw New Exception(UsbDevice.LastErrorString) End If LastDataEventDate = DateTime.Now While (DateTime.Now - LastDataEventDate).TotalMilliseconds < 100 End While ' Always disable and unhook event when done. reader.DataReceivedEnabled = False reader.DataReceived -= (AddressOf OnRxEndPointData) Console.WriteLine(vbCr & vbLf & "Done!" & vbCr & vbLf) Else Throw New Exception("Nothing to do.") End If Catch ex As Exception Console.WriteLine() Console.WriteLine((If(ec <> ErrorCode.None, ec & ":", [String].Empty)) & ex.Message) Finally If MyUsbDevice IsNot Nothing Then If MyUsbDevice.IsOpen Then ' If this is a "whole" usb device (libusb-win32, linux libusb-1.0) ' it exposes an IUsbDevice interface. If not (WinUSB) the ' 'wholeUsbDevice' variable will be null indicating this is ' an interface of a device; it does not require or support ' configuration and interface selection. Dim wholeUsbDevice As IUsbDevice = TryCast(MyUsbDevice, IUsbDevice) If Not ReferenceEquals(wholeUsbDevice, Nothing) Then ' Release interface #0. wholeUsbDevice.ReleaseInterface(0) End If MyUsbDevice.Close() End If End If MyUsbDevice = Nothing ' Free usb resources UsbDevice.[Exit]() ' Wait for user input.. Console.ReadKey() End Try End Sub Private Shared Sub OnRxEndPointData(sender As Object, e As EndpointDataEventArgs) LastDataEventDate = DateTime.Now Console.Write(Encoding.[Default].GetString(e.Buffer, 0, e.Count)) End Sub End Class End Namespace
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Create a new console application in your favorite designer.
Verify your project references:
System.dll
LibUsbDotNet.dll
Add/edit the main class. Copy/Paste code from one of the examples above.
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