HP 54540 Series - Page 87

Trigger
Common Trigger Softkeys
Common Trigger Softkeys
The top two softkeys are common to all of the trigger modes. The remaining
trigger keys are discussed in the topic for each of the trigger modes.
You set the trigger level for the TV and Glitch trigger modes in the TV and
glitch trigger menus.
Trig’d/Auto Softkey
The trig’ d (triggered)/auto softkey toggles between the two trigger
modes. The current selection is displayed in inverse video.
Triggered The oscilloscope displays data only after all of the trigger
conditions are met. The triggered mode keeps the oscilloscope from
displaying data on the screen before a specific trigger event occurs.
After each trigger event, the trigger circuit is rearmed for the next trigger
event.
Auto After the trigger circuit is armed, the oscilloscope waits for a
trigger to occur. If a trigger does not occur, the oscilloscope triggers
itself, and the data that is acquired with the trigger is displayed on the
screen. The rate at which auto trigger occurs is dependent upon the
sweep speed setting.
Use the Auto mode when you are unsure how to setup the trigger menu to
trigger the oscilloscope. This mode forces the oscilloscope to trigger if a
trigger event is not found, giving you glimpses of the signal, which then
allows you to set up the oscilloscope to display the signal.
Mode Softkey
The second softkey selects the various trigger modes. The oscilloscope has
six triggering modes: edge, pattern, state, delay, TV, and glitch. Each of
these modes are discussed later in this chapter.
5-4