Basic level trigger reset

Hi,
Can Anyone explain to me about the "Basic Level trigger detection.vi". I tried using that and it works fine but i cant seem to reset the trigger... What does resetting the trigger do? What is hysteresis for?
Thanks,
Sebastian

Hello Sebastian,
Hyteresis is used to avoid problems due to noise during the electrical interpretation of an input signal level. The following link tells you a bit more about the Schmitt Trigger that uses hysteresis. Regarding the hysteresis input of the "Basic Level trigger detection.vi" this is the way it works:
hysteresis specifies the amount above and below level through which signal in must pass before a trigger level crossing is detected. Trigger hysteresis is used to prevent noise from causing a false trigger. For a rising edge slope, the signal must pass below level – hysteresis before a trigger level crossing is detected. For a falling edge slope, the signal must pass above level + hysteresis before a trigger level crossing is detected
 The reset signal is used to force the reset of the input signal on the next call of the VI. If such a reset is inactive, the VI stores the last input signal value and will use it as the initial value the next time the VI is called. Please note that this input is defined as FALSE by default
Hope this helps you.
Best regards
Mathieu STEINER
NI France
Message Edité par Mathieu Steiner le 08-14-2006 05:02 AM
Message Edité par Mathieu Steiner le 08-14-2006 05:03 AM
Mathieu Steiner, Test System Engineer, Safran Engineering
CLD, ISTQB

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