AI Engines can directly communicate through the AXI4-Stream interconnect without any DMA and memory interaction. As shown in the following figure, data can be sent from one AI Engine to another through the streaming interface in a serial fashion, or the same information can be sent to an arbitrary number of AI Engine tiles using a multicast communication approach. The streams can go in north/south and east/west directions. In all the streaming cases there are built-in hand-shake and backpressure mechanisms.
Note: In a multicast communication approach, if one of the receivers is not ready the whole broadcast will stop until all receivers are ready again.
Figure 1. AI Engine to AI Engine Data Communication via AXI4-Stream Interconnect