DAQmx Timing Properties
- Updated2023-02-21
- 7 minute(s) read
DAQmx Timing Properties
Use the DAQmx Timing properties to configure the sample timing and duration of a task.
| Property | Description |
|---|---|
| Sample Quantity:Sample Mode | Specifies if a task acquires or generates a finite number of samples or if it continuously acquires or generates samples. Details |
| Sample Quantity:Samples Per Channel | Specifies the number of samples to acquire or generate for each channel if SampQuant.SampMode is Finite Samples. If SampQuant.SampMode is Continuous Samples, NI-DAQmx uses this value to determine the buffer size. Details |
| Sample Timing Type | Specifies the type of sample timing to use for the task. Details |
| Sample Clock:Rate | Specifies the sampling rate in samples per channel per second. If you use an external source for the Sample Clock, set this input to the maximum expected rate of that clock. Details |
| Sample Clock:Maximum Rate | Indicates the maximum Sample Clock rate supported by the task, based on other timing settings. For output tasks, the maximum Sample Clock rate is the maximum rate of the DAC. For input tasks, NI-DAQmx calculates the maximum sampling rate differently for multiplexed devices than simultaneous sampling devices. Details |
| Sample Clock:Source | Specifies the terminal of the signal to use as the Sample Clock. Details |
| Sample Clock:Active Edge | Specifies on which edge of a clock pulse sampling takes place. This property is useful primarily when the signal you use as the Sample Clock is not a periodic clock. Details |
| Sample Clock:Overrun Behavior | Specifies the action to take if Sample Clock edges occur faster than the device can handle them. Details |
| Sample Clock:Underflow Behavior | Specifies the action to take when the onboard memory of the device becomes empty. In either case, the sample clock does not stop. Details |
| Sample Clock:Timebase Divisor | Specifies the number of Sample Clock Timebase pulses needed to produce a single Sample Clock pulse. Details |
| Sample Clock:Terminal | Indicates the name of the internal Sample Clock terminal for the task. This property does not return the name of the Sample Clock source terminal specified with SampClk.Src. Details |
| Sample Clock:Timebase:Rate | Specifies the rate of the Sample Clock Timebase. Some applications require that you specify a rate when you use any signal other than the onboard Sample Clock Timebase. NI-DAQmx requires this rate to calculate other timing parameters. Details |
| Sample Clock:Timebase:Source | Specifies the terminal of the signal to use as the Sample Clock Timebase. Details |
| Sample Clock:Timebase:Active Edge | Specifies on which edge to recognize a Sample Clock Timebase pulse. This property is useful primarily when the signal you use as the Sample Clock Timebase is not a periodic clock. Details |
| Sample Clock:Timebase:Master Timebase Divisor | Specifies the number of pulses of the Master Timebase needed to produce a single pulse of the Sample Clock Timebase. Details |
| Sample Clock:Timebase:Terminal | Indicates the name of the internal Sample Clock Timebase terminal for the task. This property does not return the name of the Sample Clock Timebase source terminal specified with SampClk.Timebase.Src. Details |
| Sample Clock:Digital Filter:Enable | Specifies whether to apply the pulse width filter to the signal. Details |
| Sample Clock:Digital Filter:Minimum Pulse Width | Specifies in seconds the minimum pulse width the filter recognizes. Details |
| Sample Clock:Digital Filter:Timebase:Source | Specifies the input terminal of the signal to use as the timebase of the pulse width filter. Details |
| Sample Clock:Digital Filter:Timebase:Rate | Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute settings for the filter. Details |
| Sample Clock:Digital Synchronization:Enable | Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of the device. Details |
| Sample Clock:Write Waveform:Use Initial Waveform dt | Specifies that the value of SampClk.Rate will be determined by the dt component of the initial DAQmx Write waveform input for Output tasks. Details |
| Handshake:Delay After Transfer | Specifies the number of seconds to wait after a handshake cycle before starting a new handshake cycle. Details |
| Handshake:Start Condition | Specifies the point in the handshake cycle that the device is in when the task starts. Details |
| Handshake:Sample Input Data When | Specifies on which edge of the Handshake Trigger an input task latches the data from the peripheral device. Details |
| Change Detection:Digital Input:Rising Edge Physical Channels | Specifies the names of the digital lines or ports on which to detect rising edges. The lines or ports must be used by virtual channels in the task. You also can specify a string that contains a list or range of digital lines or ports. Details |
| Change Detection:Digital Input:Falling Edge Physical Channels | Specifies the names of the digital lines or ports on which to detect falling edges. The lines or ports must be used by virtual channels in the task. You also can specify a string that contains a list or range of digital lines or ports. Details |
| Change Detection:Digital Input:Tristate | Specifies whether to tristate lines specified with ChangeDetect.DI.RisingEdgePhysicalChans and ChangeDetect.DI.FallingEdgePhysicalChans that are not in a virtual channel in the task. If you set this property to TRUE, NI-DAQmx tristates rising/falling edge lines that are not in a virtual channel in the task. If you set this property to FALSE, NI-DAQmx does not modify the configuration of rising/falling edge lines that are not in a virtual channel in the task, even if the lines were previously tristated. Set this property to FALSE to detect changes on lines in other tasks or to detect changes on output-only lines. Details |
| On Demand:Simultaneous Analog Output Enable | Specifies whether to update all channels in the task simultaneously, rather than updating channels independently when you write a sample to that channel. Details |
| Implicit:Underflow Behavior | Specifies the action to take when the onboard memory of the device becomes empty. Details |
| More:AI Convert:Active Devices | Specifies a subset of devices in the task to configure. NI-DAQmx configures all devices in the task if you do not set this property. Details |
| More:AI Convert:Rate | Specifies in Hertz the rate at which to clock the analog-to-digital converter. This clock is specific to the analog input section of multiplexed devices. Details |
| More:AI Convert:Maximum Rate | Indicates the maximum convert rate supported by the task, given the current devices and channel count. Details |
| More:AI Convert:Source | Specifies the terminal of the signal to use as the AI Convert Clock. Details |
| More:AI Convert:Active Edge | Specifies on which edge of the clock pulse an analog-to-digital conversion takes place. Details |
| More:AI Convert:Timebase Divisor | Specifies the number of AI Convert Clock Timebase pulses needed to produce a single AI Convert Clock pulse. Details |
| More:AI Convert:Timebase:Source | Specifies the terminal of the signal to use as the AI Convert Clock Timebase. Details |
| More:AI Convert:Delay From Sample Clock:Delay Units | Specifies the units of DelayFromSampClk.Delay. Details |
| More:AI Convert:Delay From Sample Clock:Delay | Specifies the amount of time to wait after receiving a Sample Clock edge before beginning to acquire the sample. This value is in the units you specify with DelayFromSampClk.DelayUnits. Details |
| More:AI Convert:Digital Filter:Enable | Specifies whether to apply a digital filter to the AI Convert Clock. Details |
| More:AI Convert:Digital Filter:Minimum Pulse Width | Specifies in seconds the minimum pulse width the filter recognizes. Details |
| More:AI Convert:Digital Filter:Timebase:Source | Specifies the terminal of the signal to use as the timebase of the digital filter. Details |
| More:AI Convert:Digital Filter:Timebase:Rate | Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute settings for the filter. Details |
| More:AI Convert:Digital Synchronization:Enable | Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of the device. Details |
| More:Master Timebase:Rate | Specifies the rate of the Master Timebase. Details |
| More:Master Timebase:Source | Specifies the terminal of the signal to use as the Master Timebase. On an E Series device, you can choose only between the onboard 20MHz Timebase or the RTSI7 terminal. Details |
| More:Reference Clock:Rate | Specifies the frequency of the Reference Clock. Details |
| More:Reference Clock:Source | Specifies the terminal of the signal to use as the Reference Clock. Details |
| More:Synchronization Pulse:Type | Specifies the type of sync pulse used in the task. Details |
| More:Synchronization Pulse:Digital Edge:Source | Specifies the terminal of the signal to use as the synchronization pulse. The synchronization pulse resets the clock dividers and the ADCs/DACs on the device. Details |
| More:Synchronization Pulse:Time:When | Specifies the start time of the sync pulse. Details |
| More:Synchronization Pulse:Time:Timescale | Specifies the timescale to be used for timestamps for a sync pulse. Details |
| More:Synchronization Pulse:Synchronization Time | Indicates in seconds the delay required to reset the ADCs/DACs after the device receives the synchronization pulse. Details |
| More:Synchronization Pulse:Minimum Delay To Start | Specifies in seconds the amount of time that elapses after the master device issues the synchronization pulse before the task starts. Details |
| More:Synchronization Pulse:Reset Time | Indicates in seconds the amount of time required for the ADCs or DACs on the device to reset. When synchronizing devices, query this property on all devices and note the largest reset time. Then, for each device, subtract the value of this property from the largest reset time and set SyncPulse.ResetDelay to the resulting value. Details |
| More:Synchronization Pulse:Reset Delay | Specifies in seconds the amount of time to wait after the Synchronization Pulse before resetting the ADCs or DACs on the device. When synchronizing devices, query SyncPulse.ResetTime on all devices and note the largest reset time. Then, for each device, subtract the reset time from the largest reset time and set this property to the resulting value. Details |
| More:Synchronization Pulse:Terminal | Indicates the name of the internal Synchronization Pulse terminal for the task. This property does not return the name of the source terminal. Details |
| More:Synchronization Clock:Interval | Specifies the interval, in Sample Clock periods, between each internal Synchronization Clock pulse. NI-DAQmx uses this pulse for synchronization of triggers between multiple devices at different rates. Refer to device documentation for information about how to calculate this value. Details |
| Advanced:Sample Timing Engine | Specifies which timing engine to use for the task. Details |
| Advanced:First Sample Timestamp:Enable | Specifies whether to enable the first sample timestamp. Details |
| Advanced:First Sample Timestamp:Timescale | Specifies the timescale to be used for the first sample timestamp. Details |
| Advanced:First Sample Timestamp:Value | Indicates the timestamp of the first sample. Details |
| Advanced:First Sample Clock Time:When | Specifies the time of the first sample clock pulse. Details |
| Advanced:First Sample Clock Time:Timescale | Specifies the timescale to be used for the value of FirstSampClk.When. Details |
| Advanced:First Sample Clock Time:Offset | Specifies, in seconds, the offset to apply to the FirstSampClk.When value. This offset modifies when the first sample clock occurs and is used to account for known delays in the signal path. Details |