Owner's manual

38 Function Block and Operation Theory

The trigger event occurs after the specified amount of data has

been acquired. However, if the trigger event occurs before the

specified amount of data has been acquired, the acquisition

engine will ignore the trigger signal until the specified amount of

data has been acquired. Refer to Figure 4-12 for an example.

Figure 4-12: Pre-trigger Mode Operation

4.6.3 Middle-trigger Acquisition

Use middle-trigger acquisition when you want to collect data

before and after the trigger event. The amount of stored data

before and after trigger event can be set individually (M and N

samples), as illustrated in Figure 4-13.

Figure 4-13: Middle-trigger Mode Operation

Please note that trigger event can only accepted when the speci-

fied amount of data has been acquired (M samples). If the sam-

pled data is not enough, the trigger event will be ignored.

Time

Operation start

Acquisition start

Trigger

Data

Trigger Event Occurs

Acquisition stop

Begin to transfer data to system

N samples

X samples have been acquired

before trigger occurs, where

X<N

Trigger signals that occur before

the specified amount of data has

been acquired will be ignored.