DAQmxCfgAnlgEdgeRefTrig

NI-DAQmx C Functions

DAQmxCfgAnlgEdgeRefTrig

int32 DAQmxCfgAnlgEdgeRefTrig (TaskHandle taskHandle, const char triggerSource[], int32 triggerSlope, float64 triggerLevel, uInt32 pretriggerSamples);

Purpose

Configures the task to stop the acquisition when the device acquires all pretrigger samples, an analog signal reaches the level you specify, and the device acquires all post-trigger samples.

Parameters

Input
Name Type Description
taskHandle TaskHandle The task used in this function.
triggerSource const char [] The name of a virtual channel or terminal where there is an analog signal to use as the source of the trigger.
For E Series devices, if you use a virtual channel, it must be the only channel in the task. The only terminal you can use for E Series devices is PFI0.
triggerSlope int32 Specifies on which slope of the signal the Reference Trigger occurs.
Value Description
DAQmx_Val_RisingSlope Trigger on the rising slope of the signal.
DAQmx_Val_FallingSlope Trigger on the falling slope of the signal.
triggerLevel float64 Specifies at what threshold to trigger. Specify this value in the units of the measurement or generation. Use triggerSlope to specify on which slope to trigger at this threshold.
pretriggerSamples uInt32 The minimum number of samples per channel to acquire before recognizing the Reference Trigger. The number of posttrigger samples per channel is equal to number of samples per channel in the NI-DAQmx Timing functions minus pretriggerSamples.

Return Value

Name Type Description
status int32 The error code returned by the function in the event of an error or warning. A value of 0 indicates success. A positive value indicates a warning. A negative value indicates an error.