CntReadStatus

Function

Retrieves the status of specified channel. Supports multi-processing.

Format

Ret = CntReadStatus ( Id , ChNo , Sts )

Parameters

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

ChNo [ VB.NET: Short ] [ C, C++: short ] [ C#: short ] [ Python: ctypes.c_short ]
Specify the channel number for retrieving.

Sts [ VB.NET: Short ] [ C, C++: short * ] [ C#: out short ] [ Python: ctypes.POINTER(ctypes.c_short) ]
Specify the address of the variable that retrieves the status. Each bit is defined as the following Definition.

D7	D6	D5	D4	D3	D2	D1	D0
AI	Z	A	B	1	U/D	EQ	U

Bit	Description	Value
D0 :U	General-purpose input status	0:General-purpose input [0] 1:General-purpose input [1]
D1 :EQ	Count match status	0:Count data matched 1:Count data not matched
D2 :U/D	Count direction status	0:In up-count 1:In down-count
D3	Not used	1 fixed
D4 :B	B-phase input status	0:B-phase input [0] 1:B-phase input [1]
D5 :A	A-phase input status	0:A-phase input [0] 1:A-phase input [1]
D6 :Z	Z-phase input status	0:Z-phase input [0] 1:Z-phase input [1]
D7 :AI	Abnormal input error detection	0:Normal 1:Abnormal

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	10101	Invalid data buffer address.
CNT_ERR_SYS_BOARD_EXECUTING	20002	Cannot use while by another device works.
CNT_ERR_SYS_CH_NO	20201	Channel number is out of range.

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

Initial Value

Remarks

Retrieves the status of specified channel.
Status can be used to confirm whether the signal of each phase of the counter operates.
As for a general-purpose input, it is more convenient to use specific function CntInputDIByte.

Please use CntReadStatusEx for "Device with sampling function".
Only a part of status can be retrieved in CntReadStatus.

When the status was read, "Abnormal input error detection"(D7:AI) is cleared.
But, if the notify of counter error is enabled by function CntNotifyCounterError, these status is always 0.

You can always read the general-purpose input even if you set other than the general-purpose by CntSetInputHardwareEvent.

"Count match register 0"(D1:EQ) is "0:Matched" on the moment which the count value is equal as "Count match register".
On the other case, "Count match register 0"(D1:EQ) is "1:Not matched".
Please use CntNotifyCountUp function when you want to recognize the edge of "Counter match" on the case for the faster frequency pulse.

Example

Retrieves the status of channel 0.

VB.NET	Dim Ret As Integer Dim Sts As Short Ret = CntReadStatus ( Id , 0 , Sts )
C, C++	long Ret; short Sts; Ret = CntReadStatus ( Id , 0 , &Sts );
C#	int Ret; short Sts; Ret = cnt.ReadStatus ( Id , 0 , out Sts );
Python	Ret = ctypes.c_long() Sts = ctypes.c_short() Ret.value = ccnt.CntReadStatus ( Id , 0 , ctypes.byref(Sts) )