Receive Length Register (RLR) - 4.3 English

AXI4-Stream FIFO LogiCORE IP Product Guide (PG080)

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4.3 English

The receive length register are shown in Store-and-Forward Mode and Cut-Through Mode. This register is used to retrieve packet length values (the number of bytes in the packet) corresponding to valid packets received. The data for the packet is stored in the Receive Data FIFO.

The RLR should only be read when a receive packet is available for processing (the receive occupancy is not zero). After the RLR is read, the receive packet data should be read from the receive data FIFO before the RLR is read again.

Note: RDFO should be read before reading RLR. Reading RLR first results in the RDFO being reset to zero.