LabVIEW
Handler to a function in LabVIEW 6.1
Hi,
Yeah, indeed.
The thing is like this: I have some functions in a dll file that are used to register a handler(callback function), to monitorize the serial port and to call the handler when a message on the serial port is received from a drive.
This functions are:
- void RegisterHandler(Function handler) - that register the callback function
- void CheckForMessages() - that check the serial channel and call the callback function when a new message is arrived.
and they have the following prototype:
void TML_EXPORT RegisterHandler(pfnCallbackRecvMsg handler);
/*******************************************************************************************
Function: Register application's handler for messages.
Input arguments:
pfnCallbackRecvDriveMsg: pointer to handler
Output arguments:
*******************************************************************************************/
/*******************************************************************************************
Function: Register application's handler for messages.
Input arguments:
pfnCallbackRecvDriveMsg: pointer to handler
Output arguments:
*******************************************************************************************/
BOOL TML_EXPORT CheckForMessages();
/*******************************************************************************************
Function: Check if there are new messages and call handler for every message received.
Input arguments:
Output arguments:
return: TRUE if no error; FALSE if error
*******************************************************************************************/
/*******************************************************************************************
Function: Check if there are new messages and call handler for every message received.
Input arguments:
Output arguments:
return: TRUE if no error; FALSE if error
*******************************************************************************************/
Now, the callback function must comply with a special prototype: void (*pfnCallbackRecvDriveMsg)(WORD var1, WORD var2, long Value); The body of this function is made by user.
I agree with you that the functions RegisterHandler and CheckForMessages must be called with Call Library Function Node. This is what I do, but what I realy don't know is how to made the callback function to be register by the RegisterHandler.VI for the CheckForMessages.VI. I thought that using the CIN I can make a C source code in which the callback function is made and when is called the CIN return a pointer to the callback function.
I made an example in Visual C++ 6.0 and is looking like this:
void __stdcall MyCallbackFunction(WORD var1, WORD var2, long Value)
{
{
if(var1 == 1 && var2 == 0x090E)
{
printf("The value is : %ld [long]\n", Value);
}
}
{
printf("The value is : %ld [long]\n", Value);
}
}
void main()
{
{
TS_RegisterHandler( &MyCallbackFunction );
while(1)
{
TS_CheckForMessages();
}
return 0;
}
while(1)
{
TS_CheckForMessages();
}
return 0;
}
If you have some ideas pelase help me....
