CntCountUpCallbackProc

Function

Registers the callback function called when the event occurs by the count match by the function CntNotifyCountUp. Supports multi-processing.

Format

Ret = CntCountUpCallbackProc ( Id , CallBackProc , Param )

Parameters

Id [ VB.NET: Short ] [ C, C++: short ] [ C#: short ] [ Python: ctypes.c_short ]
Specify the device ID retrieved from CntInit.

CallBackProc [ VB.NET: IntPtr ] [ C, C++: long * ] [ C#: IntPtr ] [ Python: ctypes.POINTER(ctypes.c_long) ]
Specify the address of callback function.

Param [ VB.NET: IntPtr ] [ C, C++: void * ] [ C#: void * ] [ Python: ctypes.c_void_p ]
Specify the address of parameter that passes the callback. Specify NULL when the parameter is unnecessary.

Return Value

Ret [ VB.NET: Integer ] [ C, C++: long ] [ C#: int ] [ Python: ctypes.c_long ]

Definition	Value	Description
CNT_ERR_SUCCESS	0	Normality completion
CNT_ERR_SYS_RECOVERED_FROM_STANDBY	7	Execute the function CntResetDevice to return from the standby mode.
CNT_ERR_DLL_INVALID_ID	10001	Invalid ID was specified.
CNT_ERR_DLL_CALL_DRIVER	10002	CNT driver can't be called (Failed in the device I/O control).
CNT_ERR_DLL_BUFF_ADDRESS	10100	Invalid data buffer address.
CNT_ERR_SYS_NOT_SUPPORTED	20001	This function can't be used by this device.

The others: (See also: Details of Error Code)

Remarks

Use this function to register the callback. The callback function is called when the interrupt event occurred. The operation of the callback function looks like the event, but it differs from the event, the window handle is unnecessary. So it is possible to use the callback function even by the application without the window.

This function is used to the interrupt notification set by the function CntNotifyCountUp by the callback. Therefore, it is necessary to set the interrupt notification condition by using the function CntNotifyCountUp beforehand.

Example

Registers the callback for the function CntNotifyCountUp.

VB.NET	Please refer to [Note of Using Visual Basic .NET].
C, C++	long Ret; Ret = CntCountUpCallbackProc ( Id , CallBackProc , this );
C#	Please refer to [Note of Using Visual C#].
Python	Ret = ctypes.c_long() Ret.value = ccnt.CntCountUpCallbackProc ( Id , CallBackProc , 0 )

See Also

CntNotifyCountUp CntStopNotifyCountUp

Callback Function

Format

void CallBackProc ( Id , wParam , lParam , Param )

Parameters

Id [ VB.NET: Short ] [ C, C++: short ] [ C#: short ] [ Python: ctypes.c_short ]
Passes the device ID retrieved from CntInit.

wParam [ VB.NET: Integer ] [ C, C++: WPARAM ] [ C#: int ] [ Python: ctypes.wintypes.WPARAM ]
LOWORD(wParam)=Channel number of count match * LOWORD shows the low-word.
HIWORD(wParam)=Direction * HIWORD shows the high-word.

[Definition of Direction]

Definition	Value	Description
CNTM_DIR_UP	1	UP
CNTM_DIR_DOWN	2	DOWN

lParam [ VB.NET: Integer ] [ C, C++: LPARAM ] [ C#: int ] [ Python: ctypes.wintypes.LPARAM ]
Comparison Value

Param [ VB.NET: IntPtr ] [ C, C++: void * ] [ C#: void * ] [ Python: ctypes.c_void_p ]
Passes the parameter specified for the function CntCountUpCallbackProc.
NULL is stored here when NULL is specified for the parameter.

Return Value

None