AioSetCntCallBackProc

Function

Registers the called callback function as an event relative to counter occurs.

Format

Ret = AioSetCntCallBackProc ( Id , CntChannel , CallBackProc , CntEvent , Param)

Parameters

Id [ C, C++ : short ] [ Python : ctypes.c_short ]
Specifies the ID retrieved from AioInit.

CntChannel [ C, C++ : short ] [ Python : ctypes.c_short ]
Sets the channel of counter.

CallBackProc [ C, C++ : long * ] [ Python : ctypes.POINTER(ctypes.c_long) ]
Specifies the address of callback function.

CntEvent [ C, C++ : long ] [ Python : ctypes.c_long ]
The event factor that invoke the callback function is specified from the following range in the macro or numerical value.
CntEvent has the following meanings in bit, it can be specified by a combination of these bits.

Event factor	Macro	Value
Event comparison count match	CNTE_DATA_NUM	00000010H
Event count overrun	CNTE_ORERR	00010000H
Event that counter operation error	CNTE_ERR	00020000H

Param [ C, C++ : void * ] [ Python : ctypes.c_void_p ]
Specifies the address of parameter passed to callback.
If the parameter isn't needed, please set NULL to it.

Return values

Ret [ C, C++ : long ] [ Python : ctypes.c_long ]

Return values	Content
0	Normality completion
7	Execute AioResetDevice function because the device has recovered from standby mode
10001	Invalid Id was specified Use the Id retrieved from AioInit to specify the Id in this function.
10002	AIO driver can't be called At first, perform AioInit function.
15100	The value of CntChannel is outside the designated range of the function
20001	This function can't be used by this device
20002	Can not use while by another device works To use this function, counter operation must be stopped.
20003	Can not use because another process is using the device When another process is using the device, all functions except for those that support multi-process can not be performed.
25100	The value of CntChannel is outside the designated range of the device being used

Remarks

This function is used to register the callback function, if any event occurs on device, the callback function will be called.

This function cannot be used on devices without counter functionality.
If the device is in operation, the function cannot be performed.

If the function AioStopCnt is performed, the callback function cannot be called.

You should not execute the functions that start/stop devices operation in the callback routine.

Example

Sets the comparison count match event, count overrun event to channel 0.

C, C++	long Ret; Ret = AioSetCntCallBackProc ( Id , 0 , CallBackProc , CNTE_DATA_NUM \| CNTE_ORERR , this );
Python	Ret = ctypes.c_long() Ret.value = caio.AioSetCntCallBackProc ( Id , 0 , CallBackProc , caio.CNTE_DATA_NUM \| caio.CNTE_ORERR , 0 )

Callback function

Format

Ret = CallBackProc ( Id , Message , wParam , lParam , Param )

Parameters

Id [ C, C++ : short ] [ Python : ctypes.c_short ]
The ID retrieved from AioInit is passed.

Message [ C, C++ : short ] [ Python : ctypes.c_short ]
The message ID that cause the callback function be invoked is passed.
Message ID is one of the following values.

Counter message factor	Macro	Value
Event comparison count match	AIOM_CNTE_DATA_NUM	1042H
Event count overrun	AIOM_CNTE_ORERR	1043H
Count operation error event	AIOM_CNTE_ERR	1044H

wParam [ C, C++ : long ] [ Python : ctypes.c_long ]
The number of counter channels is passed. 0 is fixed now.

lParam [ C, C++ : long ] [ Python : ctypes.c_long ]
The current counter value is passed.
When the comparison count match event occurs, the value specified by AioSetCntComparisonReg is passed.

Param [ C, C++ : void * ] [ Python : ctypes.c_void_p ]
The parameter specified in the function AioSetCntCallBackProc is passed.
If the parameter is specified to NULL, NULL is stored here.