Notes on using with Visual Basic .NET

Function specifications

The functions which are same as the form of WIN32API are used. There is not any function which is exclusively used for Visual Basic .Net.

Function parameters and return value

The contents of the parameters and the return value of a function are independent of the development language, and are common.
Please refer to the function reference of each driver for details.

Format of function reference

Visual Basic .NET has a different data type than previous versions of Visual Basic 5.0 and 6.0.
Please be careful when using the application created in the old version.

Notes of using callback function

When notifying an interval timer event by using callback function in Visual Basic .NET,
it is required to fix the callback function's memory address.

The following code is the sample to process an interval timer event.
For details, please refer to the sample programs.

- Declaring as global variables.

Dim gCh As GCHandle
Dim pdelegate_func As PTM_INTERVAL_CALLBACK
Dim pfunc As IntPtr

- In the Load method, initializing the delegate for interrupt process, and add a reference to prevent garbage collection from being destroyed.

pdelegate_func = New PTM_INTERVAL_CALLBACK(AddressOf CallBackProc)
gCh = GCHandle.Alloc(pdelegate_func)

- In the Close method, releasing the handle.

gCh.Free()

- Retrieving the fixed function pointer.

pfunc = Marshal.GetFunctionPointerForDelegate(pdelegate_func)

- Specifying the retrieved fixed pointer by function TimTimerCallBackProc.

Ret = TimTimerCallBackProc(Id, pfunc, Temp)