Software Assisted Trigger - Teledyne HDO9000 Operator's Manual

HDO9000 High Definition Oscilloscopes Operator's Manual

Software Assisted Trigger

Software Assisted Trigger is used to find the trigger-level crossing point closest to the hardware
trigger point. It then adjusts the time offset of the waveform so that it is aligned with the specified
trigger level and slope.
In the following figure, the white trace is the waveform at the input to software-assisted trigger
processing. The red trace shows it after processing, aligned with the trigger point indicated by the red
marker below the grid.
Note: This feature can only be used with an Edge trigger type in Normal trigger mode.
1. From the menu, choose Triggers > Trigger Setup, then touch the Software Assisted Trigger tab.
2. Touch Enable.
3. Create a trigger window by entering a Hysteresis value. This value sets a boundary above and
below the main trigger level to exclude noise.
4. Choose Auto or Normal mode; this determines the trigger behavior when trigger crossings are
not found in the trigger source waveform.
Auto mode allows all waveforms through the channel.
l
Normal mode allows waveforms only with a trigger crossing within the horizontal gate
l
region through the channel.
5. Set Start and Stop time values on the Horizontal Gate part of the Software Assisted Trigger
tab. These values control where in the waveform the software-assisted trigger processing
searches for trigger crossings.
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