NI DMM Trigger Functions

Trigger Functions

• niDMM_ConfigureTrigger
• niDMM_SendSoftwareTrigger
• niDMM_ConfigureMeasCompleteDest
• niDMM_ConfigureTriggerSlope
• niDMM_ConfigureSampleTriggerSlope
• niDMM_ConfigureMeasCompleteSlope

niDMM_ConfigureTrigger

ViStatus = niDMM_ConfigureTrigger(ViSession Instrument_Handle, ViInt32 Trigger_Source, ViReal64 Trigger_Delay)

Purpose

Configures the DMM Trigger_Source and Trigger_Delay. Refer to Triggering and Using Switches for more information.

Parameters

Input
Name	Type	Description
Instrument_Handle	ViSession	Identifies a particular instrument session. You obtain the Instrument_Handle parameter from niDMM_init or niDMM_InitWithOptions. The default is None.
Trigger_Source	ViInt32	Specifies the Trigger_Source that initiates the acquisition. The driver sets [NIDMM_ATTR_TRIGGER_SOURCE](javascript:LaunchMergedHelp('dmm.chm', 'dmmcref.chm',
'caNIDMM_ATTR_TRIGGER_SOURCE.html')) to this value. Software configures the DMM to wait until [niDMM_SendSoftwareTrigger](javascript:LaunchMergedHelp('dmm.chm', 'dmmcref.chm',
'cviniDMM_SendSoftwareTrigger.html')) is called before triggering the DMM.

Note  To determine which values are supported by each device, refer to the LabWindows/CVI Trigger Routing section.

Trigger_Delay	ViReal64	Specifies the time that the DMM waits after it has received a trigger before taking a measurement. The driver sets the NIDMM_ATTR_TRIGGER_DELAY, which means the DMM waits an appropriate settling time before taking the measurement. On the NI 4060, if you set Trigger_Delay to 0, the DMM does not settle before taking the measurement. The NI 4065 and NI 4070/4071/4072 use the value specified in Trigger_Delay as additional settling time.

Note  When using the NI 4050, Trigger_Delay must be set to NIDMM_VAL_AUTO_DELAY (-1).

Return Value

Name	Type	Description
Status	ViStatus	Reports the Status of this operation. To obtain a text description of the status code, call niDMM_GetErrorMessage. To obtain additional information concerning the error condition, use niDMM_GetError.

niDMM_SendSoftwareTrigger

ViStatus = niDMM_SendSoftwareTrigger(ViSession Instrument_Handle)

Purpose

Sends a command to trigger the DMM. Call this function if you have configured either the [NIDMM_ATTR_TRIGGER_SOURCE](javascript:LaunchMergedHelp('dmm.chm', 'dmmcref.chm', 'caNIDMM_ATTR_TRIGGER_SOURCE.html')) or [NIDMM_ATTR_SAMPLE_TRIGGER](javascript:LaunchMergedHelp('dmm.chm', 'dmmcref.chm', 'caNIDMM_ATTR_SAMPLE_TRIGGER.html')) attributes. If the [NIDMM_ATTR_TRIGGER_SOURCE](javascript:LaunchMergedHelp('dmm.chm', 'dmmcref.chm', 'caNIDMM_ATTR_TRIGGER_SOURCE.html')) and/or [NIDMM_ATTR_SAMPLE_TRIGGER](javascript:LaunchMergedHelp('dmm.chm', 'dmmcref.chm', 'caNIDMM_ATTR_SAMPLE_TRIGGER.html')) attributes are set to NIDMM_VAL_EXTERNAL or NIDMM_VAL_TTLn, you can use this function to override the trigger source that you configured and trigger the device. The NI 4050 and NI 4060 are not supported.

Parameters

Input
Name	Type	Description
Instrument_Handle	ViSession	Identifies a particular instrument session. You obtain the Instrument_Handle parameter from niDMM_init or niDMM_InitWithOptions. The default is None.

Return Value

Name	Type	Description
Status	ViStatus	Reports the Status of this operation. To obtain a text description of the status code, call niDMM_GetErrorMessage. To obtain additional information concerning the error condition, use niDMM_GetError.

niDMM_ConfigureMeasCompleteDest

ViStatus = niDMM_ConfigureMeasCompleteDest(ViSession Instrument_Handle, ViInt32 Meas_Complete_Destination)

Purpose

Specifies the destination of the DMM Measurement Complete (MC) signal. Refer to Triggering for more information.

Parameters

Input
Name	Type	Description
Instrument_Handle	ViSession	Identifies a particular instrument session. You obtain the Instrument_Handle parameter from niDMM_init or niDMM_InitWithOptions. The default is None.
Meas_Complete_Destination	ViInt32	Specifies the destination of the Measurement Complete signal. This signal is issued when the DMM completes a single measurement. The driver sets the NIDMM_ATTR_MEAS_COMPLETE_DEST attribute to this value. This signal is commonly referred to as Voltmeter Complete.

Note  To determine which values are supported by each device, refer to the LabWindows/CVI Trigger Routing section.

Return Value

Name	Type	Description
Status	ViStatus	Reports the Status of this operation. To obtain a text description of the status code, call niDMM_GetErrorMessage. To obtain additional information concerning the error condition, use niDMM_GetError.

niDMM_ConfigureTriggerSlope

ViStatus = niDMM_ConfigureTriggerSlope(ViSession Instrument_Handle, ViInt32 Trigger_Slope)

Purpose

Sets the NIDMM_ATTR_TRIGGER_SLOPE polarity.

Parameters

Input
Name	Type	Description
Instrument_Handle	ViSession	Identifies a particular instrument session. You obtain the Instrument_Handle parameter from niDMM_init or niDMM_InitWithOptions. The default is None.
Trigger_Slope	ViInt32	Specifies the polarity of the trigger signal on which the measurement is triggered for values of either NIDMM_VAL_POSITIVE or NIDMM_VAL_NEGATIVE. The driver sets the NIDMM_ATTR_TRIGGER_SLOPE attribute to this value.

NIDMM_VAL_POSITIVE	0	The driver triggers on the rising edge of the trigger signal.
NIDMM_VAL_NEGATIVE (default)	1	The driver triggers on the falling edge of the trigger signal.

Return Value

Name	Type	Description
Status	ViStatus	Reports the Status of this operation. To obtain a text description of the status code, call niDMM_GetErrorMessage. To obtain additional information concerning the error condition, use niDMM_GetError.

niDMM_ConfigureSampleTriggerSlope

ViStatus = niDMM_ConfigureSampleTriggerSlope(ViSession Instrument_Handle, ViInt32 Sample_Trigger_Slope)

Purpose

Sets the NIDMM_ATTR_SAMPLE_TRIGGER_SLOPE polarity.

Parameters

Input
Name	Type	Description
Instrument_Handle	ViSession	Identifies a particular instrument session. You obtain the Instrument_Handle parameter from niDMM_init or niDMM_InitWithOptions. The default is None.
Sample_Trigger_Slope	ViInt32	Specifies the polarity of the Trigger signal on which the measurement is triggered for values of either NIDMM_VAL_POSITIVE or NIDMM_VAL_NEGATIVE. The driver sets NIDMM_ATTR_SAMPLE_TRIGGER_SLOPE to this value.

Rising Edge	0	NIDMM_VAL_POSITIVE	The driver triggers on the rising edge of the trigger signal.
Falling Edge (default)	1	NIDMM_VAL_NEGATIVE	The driver triggers on the falling edge of the trigger signal.

Return Value

Name	Type	Description
Status	ViStatus	Reports the Status of this operation. To obtain a text description of the status code, call niDMM_GetErrorMessage. To obtain additional information concerning the error condition, use niDMM_GetError.

niDMM_ConfigureMeasCompleteSlope

ViStatus = niDMM_ConfigureMeasCompleteSlope(ViSession Instrument_Handle, ViInt32 Meas_Complete_Slope)

Purpose

Sets the Measurement Complete signal to either rising edge (positive) or falling edge (negative) polarity.

Parameters

Input
Name	Type	Description
Instrument_Handle	ViSession	Identifies a particular instrument session. You obtain the Instrument_Handle parameter from niDMM_init or niDMM_InitWithOptions. The default is None.
Meas_Complete_Slope	ViInt32	Specifies the polarity of the signal that is generated. The driver sets NIDMM_ATTR_MEAS_DEST_SLOPE to this value.

Rising Edge	0	NIDMM_VAL_POSITIVE	The driver triggers on the rising edge of the trigger signal.
Falling Edge (default)	1	NIDMM_VAL_NEGATIVE	The driver triggers on the falling edge of the trigger signal.

Return Value

Name	Type	Description
Status	ViStatus	Reports the Status of this operation. To obtain a text description of the status code, call niDMM_GetErrorMessage. To obtain additional information concerning the error condition, use niDMM_GetError.