How to implement ILA Cross Trigger

1) The ILA Cross Triggering function enables Cross Triggering between ILA cores and between ILA cores and processors (for example, AMD Zynq™ 7000 SoC). This feature is useful when you need to trigger between two ILA cores in different clock domains, or perform hardware/software cross-triggering between a processor and an ILA core.

To use the Cross Trigger feature, during core generation, you should configure the ILA core to have dedicated trigger input ports (TRIG_IN and TRIG_IN_ACK) and dedicated trigger output ports (TRIG_OUT and TRIG_OUT_ACK).

(Schematic diagram of the interconnection of a pair of ILA's TRIG_OUT and TRIG_IN in Block Design)

2) The RIG_OUT_ACK signal indicates to the ILA core (another ILA, user design, or processor) that TRIG_OUT was received correctly and causes the ILA to lower the TRIG_OUT signal when receiving a TRIG_OUT_ACK.

In other words, TRIG_OUT remains high until TRIG_OUT_ACK is available. If the TRIG_OUT_ACK signal is tied low, TRIG_OUT remains high until the user restarts the ILA. Only TRIG_OUT goes low. If TRIG_OUT_ACK is tied low, you can re-arm the ILA.

The figure below shows a typical cross-trigger setup where ILA2 is cross-triggered to ILA1. The TRIG_OUT signal of ILA2 is connected to the TRIG_IN signal of ILA1. TRIG_IN for ILA 1