请问 VB关于USB异步通信

如题 请教大家如何实现？有没有相关资料

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谢谢楼上的
我调用creatfile
readfile
writefile
等函数可以实现同步通信对设备的访问，但是异步通信就不能接收到下位机传送的数据
有没有人能提供一个关于异步通信的解决方案啊

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附上代码VB code:

Function FindTheHid() As Boolean
'Makes a series of API calls to locate the desired HID-class device.
'Returns True if the device is detected, False if not detected.

Dim Count As Integer
Dim GUIDString As String
Dim HidGuid As GUID
Dim MemberIndex As Long

LastDevice = False
MyDeviceDetected = False


Result = HidD_GetHidGuid(HidGuid)
Call DisplayResultOfAPICall("GetHidGuid")

'Display the GUID.
GUIDString = _
Hex$(HidGuid.Data1) & "-" & _
Hex$(HidGuid.Data2) & "-" & _
Hex$(HidGuid.Data3) & "-"

For Count = 0 To 7
'Ensure that each of the 8 bytes in the GUID displays two characters.
If HidGuid.Data4(Count) >= &H10 Then
GUIDString = GUIDString & Hex$(HidGuid.Data4(Count)) & " "
Else
GUIDString = GUIDString & "0" & Hex$(HidGuid.Data4(Count)) & " "
End If
Next Count


DeviceInfoSet = SetupDiGetClassDevs _
(HidGuid, _
vbNullString, _
0, _
(DIGCF_PRESENT Or DIGCF_DEVICEINTERFACE))