Example A: Simple Data Transfer - 12.0 English

This Figure shows an example of a simple n byte wide data transfer. 3 n bytes of data are sent requiring three data beats. s_axi_tx_tready is asserted indicating that the AXI4-Stream interface is ready to transmit data.

Figure 2-8: Simple Data Transfer

X-Ref Target - Figure 2-8

To begin the data transfer, the user application asserts s_axi_tx_tvalid and provides the first n bytes of the user frame. Because s_axi_tx_tready is already asserted, data transfer begins on the next clock edge. The data bytes are placed in data blocks and transferred through the Aurora 64B/66B channel.

To end the data transfer, the user application asserts s_axi_tx_tlast , s_axi_tx_tvalid , the last data bytes, and the appropriate TKEEP value ( 0xFF ) on the s_axi_tx_tkeep bus. The core sends the final data word in blocks, and must send an empty separator block on the next cycle to indicate the end of the frame. s_axi_tx_tready is reasserted on the next cycle so that more data transfers can continue. If there is no new data, the Aurora 64B/66B core sends idles.