Powerful Human Interface Devices Library For Delphi/C++ Builder FireMonkey Apps

NativeHID Download and Use for FireMonkey demo:

Key HID concepts:
Report -Reports are the actual data that is exchanged between a device and a software client.

•  Input Report – Data sent from the HID device to the application, typically when the state of a control changes.
• Output Report – Data sent from the application to the HID device, for example to the LEDs on a keyboard.
• Feature Report -Data that can be manually read and/or written, and are typically related to configuration information.

Report Descriptor – The Report Descriptor describes the format and meaning of the data that the device supports.
UsageTables – Contain a list with descriptions of Usages, which describe the intended meaning and use of a particular item described in the Report Descriptor. For example, a Usage is defined for the left button of a mouse.  USB-IF WorkGroup Publishes the Usage Tables. See USB-IF HID Specifications.

How to build FireMonkey applications using Native HID library:

1. Open Rad Studio 10.4 and Create a Blank Multi Device Application, use FHid.pas in the uses section.
2. Include the Library folder into Project->Options->Delphi Compiler->Search Path.

3. Create a Device instance and open,

Device := TFHidDevice.Create; // Creates an Instance of TFHidDevice
Device.Open // Open the HID Device

• OnDeviceArrival– Provide the DeviceName which arrives at the system. Using DeviceName you can open the device, show the device properties.
• OnDeviceRemoved – Provide the DeviceName which removed from the system.
• Get/SetFeatureReport – Use this to manually Read/Write Related to configuration information.
• GetInputReport – Get the data sent by HID Device for the Report ID.
• SetOutputReport – Set the data to HID Device for the Report ID.

4. ShowDeviceProperties.

with Device do
  try
    AddLine('Vendor ID: ' + IntToHex(VendorID, 4));
    AddLine('Product ID: ' + IntToHex(ProductID, 4));
    AddLine('Version number: ' + IntToHex(VersionNumber, 4));
    AddLine('Serial number: ' + SerialNumber);
    AddLine('Manufacturer: ' + Manufacturer);
    AddLine('Product: ' + Product);
    AddLine('Usage page: ' + IntToStr(UsagePage));
    AddLine('Usage: ' + IntToStr(Usage));
    AddLine('Input report length: ' + IntToStr(InputReportLength));
    AddLine('Output report length: ' + IntToStr(OutputReportLength));
    AddLine('Feature report length: ' + IntToStr(FeatureReportLength));
    AddLine('Input buffer count: ' + IntToStr(InputBufferCount));
    for I := 1 to 255 do
      if HasString[I] then
        AddLine('String ' + IntToStr(I) + ': ' + Strings[I])
      else
        Break;
  except
    on E: Exception do
      AddLine('Exception: ' + E.Message);
  end;

5. Get Device Names,

var   DeviceNames : TWStringDynArray; begin   With Device do     DeviceNames := Enumerate; end;

6. For each DeviceNames GetFeatureReport, GetInputReport and Read data by reopening the device in Read-only,

with Device do
  // Feature Report
  if FeatureReportSupported then
    for J := 0 to 9 do
      try
        AddLine('Feature report ' + IntToStr(J) + ': ' + ByteArrayToString(GetFeatureReport(J)));
      except
      on E: Exception do
        AddLine('Feature report ' + IntToStr(J) + ' exception: ' + E.Message);
      end;
   // Input Report   
   if InputReportSupported then
     for J := 0 to 9 do
       try
         AddLine('Input report ' + IntToStr(J) + ': ' + ByteArrayToString(GetInputReport(J)));
       except
       on E: Exception do
         AddLine('Input report ' + IntToStr(J) + ' exception: ' + E.Message);
       end;
   // Open Device read only
   if ReadSupported then
   begin
     // reopen device with read access
     Open(DeviceNames[I], True, False);
       for J := 0 to 9 do
         try
           AddLine('Read: ' + ByteArrayToString(Read(300)));
         except
         on E: Exception do
           AddLine('Read exception: ' + E.Message);
         end;
    end;

7. Close the Device.

Device.close // Close the HID Device.

Native HID Library for FireMonkey Code demo :

Conclusion:  It’s quite easy to interact with HID in your FireMonkey applications. WINSOFT saved our time in nailing the Windows HID API and help us to build quickly using NativeHID Library.  

Head over and check out the full WINSOFT Native HID Library for Access in Delphi and C++Builder.