CntGetChannelSignal

Function

Gets the external signal source. (TTL/Photocoupler/Differential)

Format

Ret = CntGetChannelSignal ( Id , ChNo , SigType )

Parameters

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

ChNo [ C, C++ : short ] [ Python: ctypes.c_short ]
Specifies the channel number which you want to get for.

SigType [ C, C++ : short * ] [ Python: ctypes.POINTER(ctypes.c_short) ]
Specifies the address of the variable that stores the external signal source. As for the external signal source, one of the following defined values is returned.

Definition	Value	Description
CNT_SIGTYPE_ISOLATE	0	Photocoupler insulation
CNT_SIGTYPE_TTL	1	TTL
CNT_SIGTYPE_LINERECEIVER	2	Differential

In the case of CNT-3204IN-USB, CNT_SIGTYPE_ISOLATE (Photocoupler insulation) is returned regardless of the value selected by CntSelectChannelSignal.

Return Value

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

Definition	Value	Description
CNT_ERR_SUCCESS	0	Normal Complete
CNT_ERR_DLL_INVALID_ID	10001	Invalid ID is specified.
CNT_ERR_DLL_CALL_DRIVER	10002	Driver cannot be called (failed in ioctl).
CNT_ERR_SYS_CH_NO	20201	Channel number is outside the range.

The other errors: (See also: Details of Error Code)

Initial Value

CNT24-4(PCI)H : Photocoupler insulation
CNT24-4D(PCI)H : Differential
CNT-3204MT-LPE, CNT32-4MT(LPCI), CNT-3208M-PE, CNT32-8M(PCI) : TTL
CNT-3204IN-ETH, CNT-3204IN-USB : Photocoupler insulation
CPI-CNT-3201I, CPS-CNT-3202I, CPSN-CNT-3201I, CPSN-CNT-3201I2 : Photocoupler insulation

Remarks

Gets the external signal source for the specified channel.

Example

C, C++	Ret = CntGetChannelSignal(Id, ChNo, &SigType);
Python	Ret = ccnt.CntGetChannelSignal(Id, ChNo, ctypes.byref(SigType))