Stream Switch FIFO - 2022.2 English

AI Engine Kernel and Graph Programming Guide (UG1079)

Document ID
UG1079
Release Date
2022-10-19
Version
2022.2 English

The AI Engine has two 32-bit input AXI4-Stream interfaces and two 32-bit output AXI4-Stream interfaces. Each stream is connected to a FIFO both on the input and output side, allowing the AI Engine to have a four word (128-bit) access per four cycles, or a one word (32-bit) access per cycle on a stream. A fifo_depth() constraint specification below 40 allocates FIFOs from the stream switch. The following is an example of a FIFO allocation on the stream switch requesting a fifo_depth(8).

Figure 1. FIFO Allocation on Stream Switch