Trigger on a pattern
Use the following procedure to trigger the instrument when the logic inputs cause the selected function to become True or False.
You can also specify that the logic conditions must be satisfied for a specific amount of time before the instrument triggers.
1. Push the front-panel Advanced button.
2. In the Trigger control window, Open the A Event tab.
3. Select Pattern from the Trigger Type drop-down list.
4. Select a value from the Input Threshold drop-down list for each channel. The channel inputs combine to form a logic pattern.
Each channel can have a value of high (H), low (L), or "don't care" (X). A value is considered high if the channel input
voltage is greater than the specified threshold voltage. A value is considered low if the channel input voltage is less than the
specified threshold voltage. Use the "don't care" selection for any channels that will not be used as part of the pattern.
5. To set the Input Threshold voltages, click one of the Threshold Presets buttons to define the level type. If you selected
USER, click in the Ch <1–4> entry boxes, and then use the multipurpose knobs or pop-up keypad to set each threshold.
6. Select the Pattern Type Boolean logic function for the combination of input channels. The instrument will trigger on a clock
edge when the input waveforms match the specified logic pattern.
NOTE. See Pattern Triggers for definitions of the logic functions for pattern triggers.
7. From the Pattern drop-down list, select True to trigger the instrument when the logic patterns are true. Select False to trigger
the instrument when the logic patterns are false.
8. You can time qualify a pattern logic trigger, that is, you can specify the amount of time the Boolean logic function must be
True:
NOTE. On MSO/DPO5000B Series instruments, < or > are used instead of Less than or More Than from the Pattern drop-
down list.
a. Select Less than or More Than from the Pattern drop-down list.
b. Under Pattern, click in the Time entry box, and then use the multipurpose knob or keypad to set the time.
NOTE. When you select Less Than and specify a time, the input conditions must drive the logic function true for less
than the specified time. Conversely, the true for More Than item requires the Boolean function to be true for longer than
the time you specify.
The instrument determines the trigger point in the following manner:
â–
It waits for the logic condition to become True.
â–
It starts timing and waits for the logic function to become False.
â–
It compares the times and, if the time True is longer (More Than Time) or shorter (Less Than Time), then it
triggers a waveform display at the point the logic condition became False. This time can be, and usually is,
different from the time set.
9. You can set the mode and holdoff for all standard trigger types. Refer to trigger mode and set holdoff to learn more about
trigger mode and holdoff.
How to ?
628 DPO70000SX, MSO/DPO70000DX, MSO/DPO70000C, DPO7000C, and MSO/DPO5000B Series
To Next Page
Loading...
Need help?
General
