4-1
IM DL850E-01EN
4 Triggering
A trigger is a cue used to display the waveform on the screen. A trigger occurs when the specified trigger
condition is met, and a waveform is displayed on the screen.
Trigger Mode (MODE)
The trigger mode determines the conditions for updating the displayed waveforms. There are six trigger modes.
Auto Mode (Auto)
If the trigger conditions are met before an approximately 50 ms timeout, the DL850E/DL850EV updates the
displayed waveforms on each trigger occurrence. If not, the DL850E/DL850EV automatically updates the
displayed waveforms. Even when Auto mode is specified, the DL850E/DL850EV operates in Normal mode when
the trigger source is set to Time and a simple trigger is used.
If the time axis is set to a value that would cause the display to switch to roll mode, roll mode display will be
enabled.
Auto Level Mode (AutoLevel)
If a trigger occurs before a timeout (which is approximately 1 second), the DL850E/DL850EV updates the
waveform in the same way that it does in Auto mode. If a trigger does not occur, the DL850E/DL850EV detects
the center value of the trigger source amplitude, automatically changes the trigger level to the center value,
triggers on that value, and updates the displayed waveform. Auto-level mode is valid only if the trigger source is
an analog waveform on a channel between CH1 and CH16 (including sub channels, excluding real time math
waveforms). For all other cases, Auto Level mode operates in the same way as Auto mode.
If the time axis is set to a value that would cause the display to switch to roll mode, roll mode display will be
enabled.
Normal Mode (Normal)
The DL850E/DL850EV updates the waveform display only when the trigger conditions are met. If no triggers
occur, the display is not updated. If you want to view waveforms that the DL850E/DL850EV cannot trigger on, or
if you want to check the ground level, use Auto mode.
Single Mode (Single)
When the trigger conditions are met, the DL850E/DL850EV updates the displayed waveform once and stops
waveform acquisition.
If the time axis is set to a range that causes the display to switch to roll mode, the roll mode display will be
enabled. When the DL850E/DL850EV triggers, it begins recording data. When data has been acquired up to the
amount specified by the set record length, the waveform display stops.
N Single Mode (SingleN)
The DL850E/DL850EV acquires waveforms each time the trigger conditions are met until a specified number of
waveforms have been acquired, and then displays all the acquired waveforms. If no triggers occur, the display is
not updated.
Instant Start Mode (On Start)
Regardless of the trigger settings, when you press the START key, the DL850E/DL850EV updates the displayed
waveforms once and stops signal acquisition.
If the time axis is set to a value that would cause the display to switch to roll mode, roll mode display will be
enabled. When data has been acquired up to the amount specified by the set record length, the waveform
display stops.
• The trigger mode setting applies to all trigger types.
• When waveforms are being acquired, the trigger condition appears in the center of the bottom of the
screen.