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How do I send a cross-capture unit trigger?

How do I send a cross-capture unit trigger?

EXOSTIV IP (see general view below) provides a trigger line from each capture unit to all the others. This article shows how to use this feature.

Please proceed as follows to use the cross-capture unit trigger:

1) In the source capture unit tab, define the trigger condition.
In the example below, we define a simple source trigger from the ‘System’ capture unit, with ‘u_demo/sine_Data[15..0] == 0x0000’.

2) In the destination capture unit tab, activate the ‘Use other capture unit option’ tick box.

3) Click on the pencil icon to open the capture unit selection window and select the desired capture unit used as a source trigger.

In this example, we have selected the ‘System’ capture unit from which the trigger condition originates.
The other options include:
– ‘Invert’, to invert the source trigger condition
– ‘Common clock’, that has to be selected if the source and destination capture units share the same sampling clock. In this case, the destination capture unit will run synchronously, with cycle-accuracy on the source trigger event. If the source CU and destination CU do not share the same sampling clock, do not select this option. The source capture unit will generate an event that will be latched, and the destination capture unit will trigger ‘as soon as’ it ‘sees’ the source event in its own clock domain.

Click on ‘Done’.

4) When capturing data, you should enable the source CU and the destination CU to properly use the cross-capture unit trigger defined above.