Pause Trigger Considerations for S Series Devices

NI-DAQmx Device Considerations

Pause Trigger Considerations for S Series Devices

The source of your sample clock often can affect when your acquisition or generation pauses and resumes with the assertion and deassertion of a Pause Trigger.

Analog Input and Analog Output

When you generate analog output signals or acquire analog input signals, the generation/acquisition pauses as soon as the Pause Trigger is asserted. If the source of your sample clock is the onboard clock, the generation/acquisition resumes as soon as the Pause Trigger is deasserted.

If you are using any signal other than the onboard clock as the source of your sample clock, the generation/acquisition resumes as soon as the Pause Trigger is deasserted and another edge of the sample clock is received as shown in the following figure.

Pause triggers also require special consideration when used on a device with a pipelined ADC. See the S Series Timing Considerations for how pipelined ADCs and Pause Triggers can affect your measurement.

Counters

Continuous pulse-train generation: The pulse-train generation pauses as soon as the Pause Trigger is asserted, not at the end of a pulse. The pulse train resumes after the Pause Trigger is deasserted. A Pause Trigger elongates either the high or low pulse depending on which one was being generated at the time the Pause Trigger was asserted.

Nonbuffered edge counting: The counter stops counting edges as soon as the Pause Trigger is asserted and resumes counting edges after the Pause Trigger is deasserted.

Note Note  The NI 6154 does not support pause triggering.